Transmission shifting hard, intermittent problem

[medicdave]

Hi All-

Thanks for the help with my oil burning and cruise control questions. My '99 GL has developed another issue that's giving me heartburn, though...

About 3 months ago, during my 25-mile commute to the ambulance base where I volunteer, my transmission started acting up. After a few minutes of driving normally, it started to upshift very hard. Each upshift was accompanied by a noticeable "Bang!" and it felt like the car was hitting a pot hole.

I immediately stopped and checked the tranny fluid at a service station, but the fluid level was fine and it didn't have any burnt smell. The car has 76K miles on it and the transmission fluid was changed at 50K per the maintenance schedule. I had no choice but to continue on to the base, driving very gently.

I made a stop about 5 minutes before arriving, to pick up dry cleaning. I was in the cleaners for about 8 minutes, and when I came out the hard shifting had completely disappeared. The car drove smoothly for the next 3 months.

Now, this problem seems to recur any time I drive the car even remotely hard. We're not talking about full-throttle accelerations here, since my everyday driving stays below 2500 RPM to save on gas. But if I'm in a hurry and start driving a touch harder - crossing over 3500 RPM - then the tranny will start shifting hard within minutes. Let it sit for 10 minutes with the engine off, and the problem is gone again.

I'm hesitant to take it to the shop for 2 reasons: First, I'm going to waste a lot of the guy's time trying to reproduce the problem, since it's largely intermittent. Second, I've heard that messing with a fritzy auto tranny - especially in a FWD vehicle - is a recipe for pushing it to failure even faster. By that logic, it would be better for me to just run the thing until it dies, then replace the transmission outright.

Thoughts? Has anyone seen or experienced this problem? I'd hate to trade the car in, since it's paid off and I'm rather enjoying not having a car payment!

Thanks much,
[medic]Dave

[TLgunner]

I'm hoping someone will chime in here too! Our Intrigue does EXACTLY the same thing. Ours usually starts doing the HARD shifting if we've been sitting in traffic. It'll shift fine for a couple weeks then it'll start BANGING shifts where it feels like the engine's going to drop out of the car! It usually stops when the car has cooled off.

[BNaylor]

Don't feel alone. This is a common problem in GM "W" body type cars with the 4T65E tranny. A lot of things can cause it from mechanical wear, internal slipping, leakage, torque convertor to maybe the Pressure Control Solenoid or TCC-PWM solenoid, etc. GM has a TSB out on several issues concerning the 4T65E across several platforms, one mentions specifically the harsh shifting, shudders and suggests that the PCS solenoid will fix it. Some experience a whining sound too. For many if you turn the engine off for awhile and re-start the problem may disappear then show up again....very intermittent. Most of the time no manufacturer specific DTC error codes (P18XX) will show up with an odb-ii scanner that is capable of reading beyond generic codes. Many times no SES/CEL light either. I believe that the harsh shifting is associated with high line pressure due to the fault.

Either way you might want to get it into a reputable tranny shop and have them check it out before there is any major damage.

[medicdave]

OK, a few questions:

1) Do all Intrigues have the 4T65-E tranny? If not, where can I find out if mine does?

2) After some Google searching, it looks like TSB #00-07-30-002B describes the problem. Does anyone have access to TSBs who could forward it to me? I can PM you my fax number or e-mail address.

3) One web site reports that the PCS service will cost $45.61 for the part and about $273 for labor. Does this sound right?

Thanks,
[medic]Dave

[BNaylor]

Originally Posted by medicdave

OK, a few questions:

1) Do all Intrigues have the 4T65-E tranny? If not, where can I find out if mine does?

2) After some Google searching, it looks like TSB #00-07-30-002B describes the problem. Does anyone have access to TSBs who could forward it to me? I can PM you my fax number or e-mail address.

3) One web site reports that the PCS service will cost $45.61 for the part and about $273 for labor. Does this sound right?

Thanks,
[medic]Dave

The 4T65E is supposed to be the flagship tranny on all FWD GM cars with the "W" body platform, Buick, Olds, Pontiac, Chevy from 1997 and up with 3.4L, 3.5L, 3800 Series II and 3800 Series II supercharged.

Check out your owners's manual in the capacities and specifications section around Chapter 6 and it should state which automatic transaxle you have.

Another easy way to tell is pop the hood, from the driver's side looking down at the right side of the engine you'll see the tranny side cover. Up top is a cable going into it with a gray colored connector plug. GM calls this the 20 or 25 way connector. If you can get a tranny shop to replace the PCS solenoid and part for under $400 it is a good deal and acceptable. To save money tell them you want no R&R and just change the solenoid only. The PCS solenoid can be replaced without totally removing the transmission. Easy job for any tranny shop.

[kmohr3]

I know for a fact that the 98 Intrigues had a 4T60 trans. However, to check for sure look at the SPID label on the underside of the trunk lid and look for the code MN3. If you have MN3 it's the 4T65-E. I have a 2002 with the 65 trans - no problems yet, but I always have that fear in the back of my mind. They also like to trash out a sun gear and one of the planet sets, and some of them lose overdrive due to a stripped out spline on one of the shafts.

[BNaylor]

Originally Posted by kmohr3

I know for a fact that the 98 Intrigues had a 4T60 trans. However, to check for sure look at the SPID label on the underside of the trunk lid and look for the code MN3. If you have MN3 it's the 4T65-E.

I agree. MN3 is the correct RPO code if your GM "W" body to include the Intrigue model has the 4T65E autotransaxle.

[KustomMerc]

this sounds like what's happening to me as well. I own a 2005 Cadillac DTS

it has been in for this problem 3 times and coming out yesterday they still say there is no problem....

My car gets to the point of shifting very, very hard , in all gears, until I pull over and turn off the car pull the key , open the door. then restart. sometimes it will be fine for hours, sometimes for days. I never get a engine light. cadillac says there are no codes to pick up. They all act as if I'm a complete idiot. and off I go.

To add to this I started having a hissing noise come from the steering column. when I open the door you could hear it from under the car as well. it would only happen when the wheel was in a neutral postion. tuning the wheel just slighty in either direction would make it stop. Ok I take it in and the say bad pressure hose on the PS pump. didn't fix it. then they said oh.. you need a new pump. ok didn't fix it. finally they put in a new rack... ok the hissing is a little less but.... didn't fix it. My freind says it is the pressure valve in the rack and since they used recond. parts I got the same problem. again the car left yesterday... with them saying....oh thats normal noise from a car like this........ I'm ready to jump ship .....frusrtaited