'00 Trans: 1-2 late, won't shift into R or 4

Short Version:
2000 Blazer 4x4, 4.3L V6, 4L60E trans, 118k
-High-revving between 1-2 shift (~3000 rpm / 20 mph)
-Will not engage reverse gear
-Will not shift into OD
-2-3 shift is fine
-No service engine soon light
-Stepping on brake and revving requires a firm foot on the brake to keep it from moving, indicating no major slippage. However, there is a change in sound at about 1500 rpm (where the 1-2 shift would normally occur) that sounds like it could be pump cavitation—sucking air.

Long version:
I bought a 2000 Blazer with 118k miles about a month and a half ago. The transmission fluid was slightly discolored, but did not smell burnt and everything shifted fine. I have since driven it about 1000 miles, ~300 of which was last weekend. After getting back from the trip I noticed it seemed like I had to give it quite a bit of gas to back up the driveway to my garage. Since I had about 500 lbs of DJ equipment in it and my driveway is fairly steep I didn’t think much of it.

I drove it on several short trips Sunday evening, Monday, and yesterday and everything was fine. This morning while driving to work I noticed it seemed to be revving a lot between the 1-2 shift. Once into 2nd everything was fine. A few hours later I went to leave for class, shifted into reverse, and had nothing. I stress—NOTHING. It does not make any sound (like the clunk you generally get when shifting an automatic into gear) and will rev just like it’s in neutral. I pulled the tranny dipstick and the level seemed to be ok, but I didn’t have anything to wipe it off with to check it exactly. The parking lot was damn near perfectly level, but fortunately there wasn’t a car parked opposite me… I was able to drive over the sidewalk/curb thing between the two rows of cars and was only a couple minutes late to class.

While driving to class, and from class home, I experienced the same high-revving 1-2 shift and lack of reverse. After doing some research online, I tried disconnecting the negative battery cable for a minute or so to reset the computer. No improvement. I drove around a little bit, found a level parking lot, and checked the fluid level. It was about in the middle of the operating range so I dumped in about a 1/2 quart of ATF. No change.

I needed to run back downtown because I forgot my PDA at work, so I stopped by O’Reilly’s and picked up a bottle of K&W Trans-X. This was recommended to me once by my family mechanic, and will generally improve any transmission problem resulting from slipping clutches/leaking seals. Decided to take it out on the highway to get things circulated, and discovered it also would not shift into 4th gear. Trans-X exhibited no change in the transmission’s operation.

In another parking lot I decided to do a ghetto load test—step on the brake and gas at the same time. I found I had to step on the brake pretty hard to keep it from moving, which leads me to believe the clutches are fine. However at about 1500 rpm the sound coming from the engine/transmission would change. Recalling THIS THREAD (http://www.automotiveforums.com/vbulletin/showthread.php?t=351941&page=2&pp=15) , I noted that it could be consistent with air being sucked into the trans’s hydraulic system.

To save you the trouble of reading that if you don’t want to, that owner had similar problems on an '01, and upon dropping the pan found that the transmission filter came out with it--and therefore had not been properly seated in the intake port.

I also understand 4L60E's have a fairly common issue with a pressure solenoid that can cause late 1-2 shifts... can this also affect 4th and R?

There are not any Autozones locally that I could go to to have codes checked, but as I mentioned in the short version the SES light has never come on (other than the normal pre-startup self test). I don't have anything too major going on this weekend, so I'm tempted to drop the pan and see what I find. Any thoughts?

Instead of pulling the mechanic in a bottle routine, how about getting your transmission serviced with a new filter and new fluid and a complete flush.

Also, you do know you check the tranny fluid while the engine is running right?

Instead of pulling the mechanic in a bottle routine, how about getting your transmission serviced with a new filter and new fluid and a complete flush.

If I can find a reputable transmission shop I might... I don't know of one off-hand, though, and I'm somewhat leary of being sold a complete rebuild I don't need.


Also, you do know you check the tranny fluid while the engine is running right?

Yes. Contrary to popular belief, I am not a complete moron.

Back to the primary question I asked, what is the likelihood these symptoms might be related to a problem with the pressure solenoid or valvebody?

A question on top of his question about tranny flushes....I had heard that sometimes a tranny flush can be worse for a car than it is worth...probably because the gomers doing it don't know what the H they are doing....what are your opinions...

go to AAMCO. They are the best trans people you can go to. Before they do any kind of work they do a transmission diagnostic test to find out the problem. Believe if or not, there are things that can be done to fix a trans without doing a rebuild. But most times it will need a rebuild. In your case it sounds like you may be low on trans fluid but it could very well be much more.

If I can find a reputable transmission shop I might... I don't know of one off-hand, though, and I'm somewhat leary of being sold a complete rebuild I don't need.



Yes. Contrary to popular belief, I am not a complete moron.

Back to the primary question I asked, what is the likelihood these symptoms might be related to a problem with the pressure solenoid or valvebody?

Problems could be caused by a lack of fluid maintanence and the filter could be clogged which will hinder the gear switch over.

Any shop will be able to install a new filter and flush the transmission, you don't need a tranny shop for that.

Problems could be caused by a lack of fluid maintanence and the filter could be clogged which will hinder the gear switch over.

Any shop will be able to install a new filter and flush the transmission, you don't need a tranny shop for that.

Since you seem to be dead set on a flush-n-fill, would you care to explain HOW this would cause two gears to stop engaging and one gear to not upshift correctly, overnight, while the other two gears still work perfectly?

Call me a skeptic if you want, but it sounds pretty far-fetched to me. If the filter was clogged wouldn't it affect all gears equally, or at least semi-equally?

What do you have to lose?

100 flush and fill.

1500 tranny rebuild.

I have seen this because the filter is plugged and can't create proper pressure.

Also, if you want, reset the computer by pulling the negative battery cable and the two ECM fuses in the fuse panel to reset the computer.

The tranny is computer controlled so it could be logic lock in the computer and the reset might clear it.

A question on top of his question about tranny flushes....I had heard that sometimes a tranny flush can be worse for a car than it is worth...probably because the gomers doing it don't know what the H they are doing....what are your opinions...

I also have heard this, but extended to include not changing the fluid either. The reasoning I heard is that if a transmission has been neglected it's better to run it with the deposits stuck to the parts as long as you can, as opposed to putting in new ATF, or in the case of the flush, solvent, that will break the deposits loose and muck up the internals.

I would tend to buy into it, at least in some instances. I had an 84 chevy van (305/700R4) that the transmission fluid was pretty bad when I bought it. I drained it, replaced the filter and filled it back up with fresh fluid. About 150 miles later I didn't have 3rd gear anymore. I also had an '80 Cadillac (368/TH400) with absolutely THE SHITTIEST looking trans fluid I'd ever seen. I never changed it because I was scared to, and it never gave me a single problem.

I also have heard this, but extended to include not changing the fluid either. The reasoning I heard is that if a transmission has been neglected it's better to run it with the deposits stuck to the parts as long as you can, as opposed to putting in new ATF, or in the case of the flush, solvent, that will break the deposits loose and muck up the internals.

I would tend to buy into it, at least in some instances. I had an 84 chevy van (305/700R4) that the transmission fluid was pretty bad when I bought it. I drained it, replaced the filter and filled it back up with fresh fluid. About 150 miles later I didn't have 3rd gear anymore. I also had an '80 Cadillac (368/TH400) with absolutely THE SHITTIEST looking trans fluid I'd ever seen. I never changed it because I was scared to, and it never gave me a single problem.

This is an old wives tail.

DJSteve, I know of a guy who worked for Ford as one of the lead persons in the engineering department for transmissions. He informed me of the same thing, if the transmission is neglected too long, it sometimes is best to leave it alone, unless you do a very, very, thorough job (perhaps like what BlazerLT suggests by doing a flush). Otherwise you risk disturbing any particles in the system.

I'd drive by a dealer and ask a tranny guy if it's the Sun Reaction shell Gear housing ?
I had the same problem at 110,000 and it was metal fatique in the housing.....the OEM's just give way in 4L60E's...

When we backup our trucks then slip them into drive this puts strain on the shell housing....over time it just gives way...

A tranny guy ( with the right scan tool) can pull the codes from tranny...and tell you on the spot....Autozone can't..I have the same scanner they have and it only reads generic codes.....

Anyway...I don't think a flush-n-fill will do squat...you will get that if they have to replace this shell gear.

It cost me about $1200 complete, of course I put in a few new parts, but it's a 10.8 hour job......

Before I did anything, I'd have it scanned and they can tell you on the spot...wouldn't dink around with Spiffy lube and flush routine...

Just a thought....

Tony- I think you're (unfortunately) on the right track. Upon google searching based on the reverse issue I found a copy of the TSB GM released about the issue in November 99, several disgruntled 4L60E owners, and more than one reference to starting a class-action lawsuit.

Was the $1200 price tag at the dealer? Most of what I had seen posted was more in the $1500-2k range.

So I've owned the blazer a month and a half, driven it less than 1000 miles, and already (presumably) found two of the expensive weak spots--I replaced the fuel pump assembly last weekend. What should I anticipate failing next? The ball joints, fortunately, seem tight.

Tony- I think you're (unfortunately) on the right track. Upon google searching based on the reverse issue I found a copy of the TSB GM released about the issue in November 99, several disgruntled 4L60E owners, and more than one reference to starting a class-action lawsuit.

Was the $1200 price tag at the dealer? Most of what I had seen posted was more in the $1500-2k range.

So I've owned the blazer a month and a half, driven it less than 1000 miles, and already (presumably) found two of the expensive weak spots--I replaced the fuel pump assembly last weekend. What should I anticipate failing next? The ball joints, fortunately, seem tight.


This was at the dealer... where I was totally satisfied with their service.

Also alot of the problems with the 4L60E's are that they are related to folks towing and the OD going in and out and hammering the tranny to death. GM did not do a very good job with this whole deal as they were puting these trannies in (IMHO) too large a vehicle, i.e. tahoes, burbans and folks would tow and blow the tranny....

Anyway....again since you may need this work done, I'd have someone like a tranny specialist or GM tranny tech check it out first. I wouldn't flush-n-fill until you know...cause you could waste $100-$200 bucks on a flush-n-fill just to find you are flushed and f**ked...if you get what I mean....been there and done that....

Your next expense/efforts should be on diagnostics so you can do it right the first time.

DJSteve, I know of a guy who worked for Ford as one of the lead persons in the engineering department for transmissions. He informed me of the same thing, if the transmission is neglected too long, it sometimes is best to leave it alone, unless you do a very, very, thorough job (perhaps like what BlazerLT suggests by doing a flush). Otherwise you risk disturbing any particles in the system.


yep and more specifically the particulates/clutch material gets into the valve body channels and mucks up the valve/shift valves.....
Hard to get out...Not a "Wives Tail" either.

Many people do the cheap flushes and it's best to do BOTh the flush AND filter change, drop the pan etc...they you get 90% of the crap out...

Don't discredit my advice.

Flush and fill could easily fix it. As said earlier it has never been serviced.

Don't discredit my advice.

Flush and fill could easily fix it. As said earlier it has never been serviced.

I've been posting on various forums for about 7-8 years now... for a moderator, you sure are arrogant. I did NOT say the trans had never been serviced. Honestly I don't know, because I've only owned the truck long enough to put on 1000 miles. In my experience the general condition of the vehicle is fairly indicative of the routine maintenance it received (or didn't), though, and this truck is VERY clean for the miles it has--no leaks or seepage anywhere, and the body and interior are viruatlly flawless.

Given that:
a) The sun shell issue with 4L60E's is very common, to the extent GM issued a TSB
b) The trans went from perfectly fine to dysfunctional overnight
c) My problems match those described in the TSB exactly
d) You consistently give unsubstantiated advice that other people refute with experience
e) I have yet to hear of ANYONE who had gears completely stop working, while others were fine, because of a clogged filter

I think I'll skip the flush-n-fill and take it someplace to get the actual problem fixed.

I've been posting on various forums for about 7-8 years now... for a moderator, you sure are arrogant. I did NOT say the trans had never been serviced. Honestly I don't know, because I've only owned the truck long enough to put on 1000 miles. In my experience the general condition of the vehicle is fairly indicative of the routine maintenance it received (or didn't), though, and this truck is VERY clean for the miles it has--no leaks or seepage anywhere, and the body and interior are viruatlly flawless.

Given that:
a) The sun shell issue with 4L60E's is very common, to the extent GM issued a TSB
b) The trans went from perfectly fine to dysfunctional overnight
c) My problems match those described in the TSB exactly
d) You consistently give unsubstantiated advice that other people refute with experience
e) I have yet to hear of ANYONE who had gears completely stop working, while others were fine, because of a clogged filter

I think I'll skip the flush-n-fill and take it someplace to get the actual problem fixed.


First of all, I wasn't talking to you in that statement.

Second of all, insulting me when I was only trying to help is against the premise of this forum.

Third, if you KNOW so much about this, why in hell did you ask the question in the first place? Go and fix it.

First of all, I wasn't talking to you in that statement.

Ok then, would you care to enlighten me who you were talking to? Because I'm pretty sure I'm the only person who has posted to this thread with a current (non-already-fixed) problem...

Second of all, insulting me when I was only trying to help is against the premise of this forum.
If you answer answer my above question in a convincing manner, I will be happy to apologize. Otherwise, pulling "facts" out of your ass is against the premise of the forum as well, so I'd guess that makes us even.

Third, if you KNOW so much about this, why in hell did you ask the question in the first place? Go and fix it.
I asked here prior to doing any serious research. So far I've gotten your suggestion that a flush-n-fill might fix it, a hint that it might be the reaction sun shell, and on another message board, a reply from a GM transmission mechanic saying it IS the reaction sun shell. Not might be, is.

For someone with 6000+ posts who trys to pass themself off as an "expert" I find it very peculiar you weren't aware of/didn't mention the TSB in the first place.

Ok then, would you care to enlighten me who you were talking to? Because I'm pretty sure I'm the only person who has posted to this thread with a current (non-already-fixed) problem...

I was talking to the others that was saying it wouldn't fix it. I have had people do this before and it did fix their problem.

If you answer answer my above question in a convincing manner, I will be happy to apologize. Otherwise, pulling "facts" out of your ass is against the premise of the forum as well, so I'd guess that makes us even.

First, you call me arrogant, now you say I am pulling facts out of my butt. That makes two insults in your last two posts when I haven't been rude to you at all. Personal insults will not be tolerated and is against forum policy. Attacking me and my advice will get you no where fast when all I was trying to do was help.

I asked here prior to doing any serious research. So far I've gotten your suggestion that a flush-n-fill might fix it, a hint that it might be the reaction sun shell, and on another message board, a reply from a GM transmission mechanic saying it IS the reaction sun shell. Not might be, is.

Ok, sure, that is your call. I was just stating what I have seen work in the past.

For someone with 6000+ posts who trys to pass themself off as an "expert" I find it very peculiar you weren't aware of/didn't mention the TSB in the first place.

Yet, another personal attack.

Sorry if I don't know every single service bulletin on the planet about our trucks, and your inference that post count automatically means I have a knowledge about the every one of 1000s of service bulletins currently out there is not my problem. My post count comes from helping hundreds, maybe even 1000s of people with their s-series problems.

If you have a problem with me helping people, that is not my concern.

Last warning..... I will not tolerate the personal attacks when I was not rude to you.

BlazerLT, since you say that a flush-and-fill has "fix their problem" in regard to others having transmission issues, has a flush-and-fill ever corrected a problem for someone who had the exact symptoms that this person has?

DJSteve, thanks for your information. Because you had mentioned this 'sun shell' that I never heard of, it made me do some research myself since I'm concerned about any transmission issues with my own Blazer. I learned something from your post. Thank-you.

BlazerLT, since you say that a flush-and-fill has "fix their problem" in regard to others having transmission issues, has a flush-and-fill ever corrected a problem for someone who had the exact symptoms that this person has?

DJSteve, thanks for your information. Because you had mentioned this 'sun shell' that I never heard of, it made me do some research myself since I'm concerned about any transmission issues with my own Blazer. I learned something from your post. Thank-you.

No situation is always EXACTLY the same.

But I have seen transmission slipping, and improper shifting caused by it.

I am just offering a potential fix, I never said it WAS the fix, I am just offering advice. Nothing more.

I was never rude nor did I say anyone else was wrong.

For your information I am a GM trained mechanic, I also am a moderator on this board.

BlazerLT's suggestion of replacing the fluid does apply and it is a known fix for some trans issues.

Yes GM has a bulletin on this problem but not all problem transmissions will be fixed by the bulletin. Just because you have the same problem with your trans doesn't mean this bulletin will fix your problem.

If you read the bulletin it does not say "If you have this problem replace these parts". What it does say is to drop your trans pan and look for metal on the magnet, which would of been done if you follow BlazerLT's advice.

As a GM dealer tech I see the people come in with bulletin in hand, telling me to do this bulletin to fix there problems. Many times the owners have failed to read the bulletin. Some times they don't have the problem and sometimes the bulletin doesn't apply to their trucks. And even sometimes they think they have the problem because they see a bulletin on it.

At the bottom of every GM bulletin is written this!

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.


Now as a moderator on AF I am appaled by some of the remarks that are posted here. I wouldn't of had a problem in handing out a ban for the insults posted. You guys have a very smart mod who wants to help you and who didn't want you banned for the insults. So stop the insults or I will be banning you using the AF guidelines the members agree to when they sign up.

Wow such talk and to think I was out of town and missed these exchanges...

I really don't know why our opinions don't seem to hold equal value but in the spirit of trying to help DJSteve as I mentioned earlier.....

The Flush and Fill is nice, but as I have learned first hand, a flush and fill which happened days earlier from my sun shell suffering metal fatique. I drove my vehicle in and the GM TECH knew exactly what it was....and he also showed me his diagnostic page, which I now own a set...on page 7-230 the only phrase it says for your symptoms is REPLACE THE SUN SHELL REACTTION assy.

DJSTEVE, plze just have a dealer pull the tranny codes and confirm our suspicion.....I suggest this only because I had the same symptoms and sharing my experiences....

BTW - BlazerLT was diggin on me for my disregard for suggesting the above and discounting his full flush and fill....so don't take offense. It was me he was blazing not you....

Please let us know how your experiences go....I hope that it isn't the above issue but suspect it is. Just trying to save you an extra $200 bucks that's all....

I thought I would post an update now that I was back on the road... the problem was caused by a broken reaction sun shell.

After being wholly unimpressed with the transmission shops in Ames I ended up taking it to a family-owned shop in Des Moines (~50 miles away). I told them I wanted it fixed right and such that towing a small trailer would not cause issues down the road.

The Blazer has 119k on it, but I've only owned it long enough to put on 1k of that. The guy said the transmission had been rebuilt at some time in the past (non-recently), but that no updates were made and there were a lot of things done in a manner they wouldn't be comfortable with sending out of their shop. Other than the sun shell the vanes in the pump were also damaged (he thought possibly related to the previous service) and the seal between the trans and transfer case was leaking slightly.

The final bill was $1850. $1052 was for parts. Their prices looked pretty comparable to what I had seen in earlier research online:
Master kit - $292
Rebuilt torque converter - $230
Force Motor - $97
Band - $25
Input Sprag - $65
Shell - $42
Filter - $29
Fluid - $20
Valve Body kit - $60
Bushing kit - $19
Boost Valve - $40
Pump Kit - $60
Manifold - $64
Valve Body Accumulator - $10

Excellent, glad you figured it out and are on the road. :D

Yes GM has a bulletin on this problem but not all problem transmissions will be fixed by the bulletin. Just because you have the same problem with your trans doesn't mean this bulletin will fix your problem.

If you read the bulletin it does not say "If you have this problem replace these parts". What it does say is to drop your trans pan and look for metal on the magnet, which would of been done if you follow BlazerLT's advice.


This is the TSB I mentioned earlier. I cannot guarantee it wasn't altered somewhere previously, but I found it in multiple places online in the exact same form--which does essentially say "if you have this problem replace these parts."

Bulletin No.: 00-07-30-022
Date: November, 2000
Subject:
No Reverse, Second Gear, or Fourth Gear
(Replace the Reaction Sun Shell)
Models:
1996 Buick Roadmaster
1996 Cadillac Fleetwood
1996 Chevrolet Caprice
1996-99 Chevrolet Camaro, Corvette
1996-99 Pontiac Firebird
1999 Cadillac Escalade
1996-99 Chevrolet and GMC C/K, M/L, S/T, and G Models
1996-99 Oldsmobile Bravada
1996-99 Holden Commodore
with Hydra-Matic 4L60-E (RPO M30) Automatic Transmission
Condition
Some owners may comment on a no reverse, no second gear, or no fourth gear
condition. All other gears will operate properly.
Cause
The reaction sun gear (673) may not hold inside the reaction sun shell (670).
Correction
Replace the reaction sun shell which has an increased radius from the splines
the to shell.

p/n 8683439 Reaction Sun Shell
Parts Information
Parts are currently available from GMSPO.


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If anyone would like to see pictures of a broken sun shell, check out http://trustmymechanic.com/forum/viewtopic.php?p=21262#21262. They were posted by a GM master technician who works as a senior transmission rebuilder (his profile doesn't show up unless you're a member and are signed in). He immediately identified the sun shell and didn't cite any other conditions which would cause my problems.

All the transmission shops I talked to who were helpful (willing to discuss the problem without charging a diagnostic fee) were familiar with this problem. It is not uncommon for 4L60E's.

My understanding is that GM issued the TSB in 1999, but didn't update the part until 2003. So if you own a 1996-2003 GM product with this transmission make SURE you come to a complete stop before shifting from R to D (or vice versa) and pray yours doesn't fail while you own the vehicle.

My wife and I have a similar problem. We have a 2000 Blazer with 79,000 miles. Off the line it lags then it picks up speed gradually. The check engine light is on and it kinda revs high as if there's a lot of weight in the car. We took it to 3 shops. 2 said it was the transmission shift solenoid and Aamco said it was a broken shell and was gonna charge us $2200. We're gonna replace the solenoid first and give you an update!

I thought I would post an update now that I was back on the road... the problem was caused by a broken reaction sun shell.

After being wholly unimpressed with the transmission shops in Ames I ended up taking it to a family-owned shop in Des Moines (~50 miles away). I told them I wanted it fixed right and such that towing a small trailer would not cause issues down the road.

The Blazer has 119k on it, but I've only owned it long enough to put on 1k of that. The guy said the transmission had been rebuilt at some time in the past (non-recently), but that no updates were made and there were a lot of things done in a manner they wouldn't be comfortable with sending out of their shop. Other than the sun shell the vanes in the pump were also damaged (he thought possibly related to the previous service) and the seal between the trans and transfer case was leaking slightly.

The final bill was $1850. $1052 was for parts. Their prices looked pretty comparable to what I had seen in earlier research online:
Master kit - $292
Rebuilt torque converter - $230
Force Motor - $97
Band - $25
Input Sprag - $65
Shell - $42
Filter - $29
Fluid - $20
Valve Body kit - $60
Bushing kit - $19
Boost Valve - $40
Pump Kit - $60
Manifold - $64
Valve Body Accumulator - $10

That's what I was afraid of when I heard your symptoms...glad you just didn't waste a 150 bucks on a flush -n- fill ...looks like you got it done right....

Unfortunately, welcome to the broken sunshell reaction club....

Good that it has been updated too....

Thanks for the link and pictures. I admit I'm ignorant when it comes to transmissions, but information like this helps us learn. The pictures of a good and damaged sun shell was interesting, atleast to me.

Glad you got it resolved.

My wife and I have a similar problem. We have a 2000 Blazer with 79,000 miles. Off the line it lags then it picks up speed gradually. The check engine light is on and it kinda revs high as if there's a lot of weight in the car. We took it to 3 shops. 2 said it was the transmission shift solenoid and Aamco said it was a broken shell and were gonna charge us $2200. We're gonna replace the solenoid first and give you an update!

From the research I did that sounds much more consistent with a PWM/TCC solenoid problem. The sun shell is engaged for R, 2, and 4... if it breaks you won't have anything in those gears, and I don't think it generally triggers a SES light (mine didn't, and everything read normal using a friend's laptop-based OBD-II scan tool).

Are you doing the solenoid replacement yourself, or taking it to a shop? As I understand it the problem is sometimes due to damage to the valve body bore and not just the solenoid. There's a fix kit from Sonnax that solves both problems, but it requires a special drill bit/tool to install. I think the kit runs about $40 online, but the tool is more like $100.

Econo Lube is fixing it. After a dianostic test they said we have to replace both a and b circuits(solenoids). They also said we need to do a transmission flush. I hope that solves our problem. We should find out by tomorrow 3-8-05.

It was the shift solenoids and now the truck's running fine. It cost $275 for parts, labor and a transmission flush. Thanks guys!

Tony- I think you're (unfortunately) on the right track. Upon google searching based on the reverse issue I found a copy of the TSB GM released about the issue in November 99, several disgruntled 4L60E owners, and more than one reference to starting a class-action lawsuit.

Was the $1200 price tag at the dealer? Most of what I had seen posted was more in the $1500-2k range.

So I've owned the blazer a month and a half, driven it less than 1000 miles, and already (presumably) found two of the expensive weak spots--I replaced the fuel pump assembly last weekend. What should I anticipate failing next? The ball joints, fortunately, seem tight.

Ball Joints - Yep that's one weakspot.
The Transmission - Yep that's another.
..-.I lost the main coolant lines on mine, almost lost it! Lucky for me,
....it wasn't damaged. New filter / fluid every 2 years - NP so far.
Wow and only 1 fuel pump! I've done about 4 fuel pumps so far!

The fuel pressure regulator is another 'issue' with the blazers. I am just getting ready to replace mine. I have a 'suspision' that a weak fuel pressure regulator can make one to swap out fuel pumps before their time. I've done 4 pumps so far! My fuel system cannot make the required 54 PSI to get the engine to start at startup.

I am suspecting that I replaced about 2 fuel pumps for nothing and that the problem may have been my fuel pressure regulator all along. Shops see the <54 PSI reading, a non-starting engine, and think "it's time to swap out the fuel pump". Once the new fuel pump installed, car runs another 1-2 years without issues.

If you get the engine running (I did this using the old fashioned PRIME the air intake with fuel trick), and I see 54-62 PSI under driving conditions. Fuel pump is able to make reasonable pressure with the engine under a load. Blocking the gas recirc line back to the tank and you see some 'decent' pressure numbers. Do not go above 70 PSI (I think 70 is the limit?? Correct me if wrong) as you can damage the fuel pressure regulator.

I have also seen issues with the EVAP system. If you remove the gas cap and you hear a hissing noise, you're about 'implode' your fuel tank. Most shops are so plagued with loose gas caps, they don't wanna look at it. I imploded my last tank with fuel pump #3. So be very carful if you hear any 'hissing' noises when you open the gas cap.

I had a friend with a 1996 cavalier, same hiss. I talked him into loosing his gas cap, while talking with him, we could readily hear his tank popping back out. All this was caused by a faulty EVAP solenoid.

Are we having fun yet?

Regards,
---- Robb ----

Short Version:
2000 Blazer 4x4, 4.3L V6, 4L60E trans, 118k
-High-revving between 1-2 shift (~3000 rpm / 20 mph)
-Will not engage reverse gear
-Will not shift into OD
-2-3 shift is fine
-No service engine soon light
-Stepping on brake and revving requires a firm foot on the brake to keep it from moving, indicating no major slippage. However, there is a change in sound at about 1500 rpm (where the 1-2 shift would normally occur) that sounds like it could be pump cavitation—sucking air.

Long version:
I bought a 2000 Blazer with 118k miles about a month and a half ago. The transmission fluid was slightly discolored, but did not smell burnt and everything shifted fine. I have since driven it about 1000 miles, ~300 of which was last weekend. After getting back from the trip I noticed it seemed like I had to give it quite a bit of gas to back up the driveway to my garage. Since I had about 500 lbs of DJ equipment in it and my driveway is fairly steep I didn’t think much of it.

I drove it on several short trips Sunday evening, Monday, and yesterday and everything was fine. This morning while driving to work I noticed it seemed to be revving a lot between the 1-2 shift. Once into 2nd everything was fine. A few hours later I went to leave for class, shifted into reverse, and had nothing. I stress—NOTHING. It does not make any sound (like the clunk you generally get when shifting an automatic into gear) and will rev just like it’s in neutral. I pulled the tranny dipstick and the level seemed to be ok, but I didn’t have anything to wipe it off with to check it exactly. The parking lot was damn near perfectly level, but fortunately there wasn’t a car parked opposite me… I was able to drive over the sidewalk/curb thing between the two rows of cars and was only a couple minutes late to class.

While driving to class, and from class home, I experienced the same high-revving 1-2 shift and lack of reverse. After doing some research online, I tried disconnecting the negative battery cable for a minute or so to reset the computer. No improvement. I drove around a little bit, found a level parking lot, and checked the fluid level. It was about in the middle of the operating range so I dumped in about a 1/2 quart of ATF. No change.

I needed to run back downtown because I forgot my PDA at work, so I stopped by O’Reilly’s and picked up a bottle of K&W Trans-X. This was recommended to me once by my family mechanic, and will generally improve any transmission problem resulting from slipping clutches/leaking seals. Decided to take it out on the highway to get things circulated, and discovered it also would not shift into 4th gear. Trans-X exhibited no change in the transmission’s operation.

In another parking lot I decided to do a ghetto load test—step on the brake and gas at the same time. I found I had to step on the brake pretty hard to keep it from moving, which leads me to believe the clutches are fine. However at about 1500 rpm the sound coming from the engine/transmission would change. Recalling THIS THREAD (http://www.automotiveforums.com/vbulletin/showthread.php?t=351941&page=2&pp=15) , I noted that it could be consistent with air being sucked into the trans’s hydraulic system.

To save you the trouble of reading that if you don’t want to, that owner had similar problems on an '01, and upon dropping the pan found that the transmission filter came out with it--and therefore had not been properly seated in the intake port.

I also understand 4L60E's have a fairly common issue with a pressure solenoid that can cause late 1-2 shifts... can this also affect 4th and R?

There are not any Autozones locally that I could go to to have codes checked, but as I mentioned in the short version the SES light has never come on (other than the normal pre-startup self test). I don't have anything too major going on this weekend, so I'm tempted to drop the pan and see what I find. Any thoughts?
Sounds like valve body. I recently had my '97 rebuilt at Aamco including replacing the shell which contains the clutches. Both parts are prone to problems resulting from heat and also poor design. If fluid isn't burnt, points at valve body. Take it to a trans shop for diagnosis, continued driving will only promote further destruction.

Sounds like valve body. I recently had my '97 rebuilt at Aamco including replacing the shell which contains the clutches. Both parts are prone to problems resulting from heat and also poor design. If fluid isn't burnt, points at valve body. Take it to a trans shop for diagnosis, continued driving will only promote further destruction.

His tranny was fixed last week.