4T65E Trans Shift Hard, P1811 DTC

[gjhunter01]

This is gjhunter01 and thought I would leave a update from my page 1 posting. I just sold my 01 Lesabre 2 weeks ago with 180k miles on it. The spring kit was installed in 4/08 with 125k miles i have not had any problems with the trans and have not even touched it since.

[cvcman]

Ok I have a 2000 Lesabre Limited with 25k on it. After i bought it it developed a hard shift in all gears with the 1811 code. The dealer replaced the valve body and EPC solenoid. It now up shifts thru every gear smooth as silk and even into lockup. The thing I notice is one hard downshift if you are going 55 mph and step on it to downshift into 2nd it is a very firm shift. If you feather the gas it will shift out of lock up smooth. If you floor it it will shift smooth its only the one downshift .Ideas ???

[Rocky69]

Well I just bought a zzperformace shift kit for my tranny. Hopefully it work on my buick century. I just got the car and now the tranny started shifting hard. I called the guy I got it from and said he had no probs with it at all. He said he just replaced the intake gaskets some I,m wondering if it over heat and damaged the tranny.

[la1]

I am wondering if some of this is electronic, like temp opens in the wires or crimps of the sockets in the 20 way connector. It is way to random to be mechanical. My 2003 Impala with a 4T65E will clunk when I first start to pull away from a stop...does not do it all the time. I did disconnect the bat and then diconnected the 20 way connector, squirted some electrical contact cleaner in both connector halves...the trans worled grat for a month, then random clunks...found if I push in on the group of wires in the 20 way connector, the trans will work great for a week or two. Going to get a 20 way connector and try.

[BNaylor]

Originally Posted by la1

I am wondering if some of this is electronic, like temp opens in the wires or crimps of the sockets in the 20 way connector. .

Not normally but it doesn't hurt to disconnect the 20 way connector and reseat. But most issues are as discussed above. Clunk from start sounds like another problem. You sure your axle shafts are good and the differential?

[la1]

Clunk from start sounds like another problem

It is not actually a clunk, it's more of a thump after driving a few feet, totally random and I can stop it by pushing in on the wire cluster on the 20 way connector. I know what a bad C/V joint is like, no matter what you do there is the metallic "clunk" when putting the trans in gear or starting off , with snaping noises when turning.

Not normally but it doesn't hurt to disconnect the 20 way connector and reseat

that won't help if there is an itermittent open in the control wiring of the 20 way connector...

sorry I still beleive it to be electronic....still under investagation.

[la1]

also the MAF can affect the trans , case in point. My sister called and said her Nissan sometimes bogged down after starting off at the light. I drove it and noticed that it would randomly start in second gear. I cleaned the MAF..problem solved. Use sensor safe cleaners.

[Mathers24]

Originally Posted by BNaylor

You'd probably want to take it a specialist like a transmission shop. Cost will vary depending on where you live. Cottman's which is also AAMCO here charged around $600 with the part. But they tried awfully hard to convince us to get a rebuild which was declined.

Or you're welcome to try my work around suggestion but at your own risk. To date all I can proudly report is none of the test vehicles where this procedure was applied have any further issues.

For the accumulator shift mod I can direct you to a place on-line that sells it. If you can DIY a pan drop service then you could do this mod or have a general mechanic do it. Also, I would highly recommend switching over to the new Dexron VI with this mod. I have noted no issues. Also, I can post pics of how the accumulator looks and how the mod is done.

I really like your explanation on the work around of the PCS. I have the ZZP shift kit and added Sea Foam a couple of days ago. My question is, should I run the Foam for a couple of weeks or is it safe to just go ahead and dump the fluid and install the shift kit. By the way, the hard up shifts haven't stopped but they have gotten better. I do have a slight whine and was wondering if the shift kit would eliminate the whine? Like so many others on this subject, I am opting not to have a shop replace my PCS.

I would rather spend the $60 or so before having a trans shop charge me $600 to $800. When I first noticed the harder up shifting, I had a lube shop drop the pan, clean out the pan and change the filter....the filter was a cheap China one. It corrected the hard shifts for about a week and then came back. Is the whine caused from the PCS and high pressure or may it be something else? I noticed the whine when it started up shifting harder. It's not real hard but I just want it to shift normal again and will use the small spacers from the kit. I have been working on cars my whole life and this seems pretty straight forward. I know I need to scuff up the bores for the 1-2 and 2-3 accumulator mod.

One last question, I am going to go with Dextron 6 and not do a flush of the converter. Will I have to do another fluid change in a month or so or can it wait until spring? Thanks for taking the time to answer my questions!

2000 Impala LS
3.8L Buick Engine
4T65e Trans

[ozzieb@aol.com]

I have the same shift problems with a 2001 Monte Carlo SS and have been trying to find the ZZ Performance shift kit for the 4T65E transmission. I cannot find this at their website. Has the kit been discontinued and are there any available online.

[powersms71]

I'm a 40 year-old female who knows very little about cars, and so, hopefully, you guys can help me here. I bought a used 1999 Buick Regal a little over 3 years ago, and when I bought it, I was told it had the hard-shifting problem. But, for the price, I bought the car anyways.

Anyways, I finally got the money about 2 years ago to get the problem fixed, and initially my mechanic thought it was just spark plugs. I had the spark plugs replaced -- issue remained. Then, finally, we did have the PCS replaced, which solved the problem for about 3 months. I took it back, and then, the dealership informed my mechanic that GM had a new part that supposedly solved this problem. So, they put the new part on free of charge, and it looked like it solved the problem. That was 13 months ago.

Then, last night, the issue has shown up again. The same old problem -- hard-shifting, along with a whining noise, after the car warms up. So, here we go again. I can see no other problems with the transmission -- beyond the hard-shifting, the car runs smooth as silk.

Do you guys have any suggestions? I am getting SO tired of this. Could it be something else? Or, is this likely to be the PCS again? I'm taking it into the shop tomorrow to have it checked out, and if it's the PCS again, I'm going to ask why they told me this new part was a "fix" and it happened again.

Thanks in advance!

Mary

[HotZ28]

Originally Posted by ozzieb@aol.com

I have the same shift problems with a 2001 Monte Carlo SS and have been trying to find the ZZ Performance shift kit for the 4T65E transmission. I cannot find this at their website. Has the kit been discontinued and are there any available online.

Click Here also you can Click Here for some good install instructions.

[HotZ28]

Originally Posted by powersms71

Could it be something else? Or, is this likely to be the PCS again? I'm taking it into the shop tomorrow to have it checked out, and if it's the PCS again, I'm going to ask why they told me this new part was a "fix" and it happened again.

Thanks in advance!

Mary

Have you had the fluid & filter replaced since you have owned the car?

[powersms71]

HOTZ28:

When they put on the new PCS 13 months ago, I think they replaced the transmission fluid (I have no clue about the filter). I will find out tomorrow, though, since I've had the same mechanic for years. Could the fluid cause these symptoms, including the whining noise? If so, why?

Thanks so much!

Mary

[HotZ28]

The location of the PCS, is totally different from the trans pan & filter. When the fluid breaks down, varnish develops and detergents in the fluid loose their cleaning capacity; therefore, contributing to sticking shift solenoids & valve body problems. I would ask the mechanic to change the fluid/filter & use Dexron VI fluid as a replacement. After the fluid/filter change, drive it for about 5K miles before condemning the PCS.

[powersms71]

Okay, I took it to the shop, the mechanic drove it around with a scanner, and he couldn't really find anything wrong. He did note that he thought the RPM was a tad bit higher than normal for the speed, and so, if he had to guess, he was thinking that I am at the beginning of the Torque Converter Clutch System going bad. However, he believes I probably still have 1-2 years before I might need a new transmission, and so, I guess for now, I'll leave it be. He did check the PCS, and it was fine.

Also, I was wrong about the dates. It's been almost 2 full years (Feb. 2010) since the new PCS was installed. So, this car has been doing fine for that long. I think that's pretty good.

Anyways, I guess I'll just wait and see. If this car lasts me another 2 years, I probably will just get another car and not do the transmission rebuild.

Any has any other thoughts? I assume that a hard-shift/whining noise would also be consistent with Torque Converter issues? (I have not looked it up yet).

Mary