CALLING ALL TRANSMISSION EXPERTS

[harrydunn]

1996 Cutlass Supreme, 3.1L, 93,000 miles--First of all, thanks for all of the good advice I've received thus far. I've posted a couple of times regarding a shudder I just started noticing when my car hits overdrive, especially when at low RPM's under load when it is straining to stay in OD instead of kicking down to Drive. I understand this to be a torque converter issue. Once the TC locks up in overdrive I hit the brake to disengage and the shudder stops, so I think I've zeroed in on the problem since I've ruled out the coil pack, plug wires, etc. I visited a second Chevrolet dealer today (I've still got a warranty) and spoke with the service manager for a good 10 minutes about the problem. He seems pretty willing to help me get to the bottom of this. Even said he'd be willing to drive it home one evening to get a good feel for it on the highway. Assuming they find nothing (like the first Chevrolet dealer where I bought it--they didn't try to hard), what are my options regarding fixing it myself? I've heard of a valve body fix. The rest of the car is in excellent condition and I'd love to get rid of this annoying little problem. My plan is to drive the car for a LONG time.

 

Thanks.

[Slade901]

You should be able to fix and replace the torque converter solenoid yourself. Guys/gals over have discussed before about replacing the torque converter solenoid. Use the search function or if those guys/gals re-post their previous message about replacing the torque converter solenoid.

[Robby1870]

yeah, all those solenoids are accessible by taking off the side pan

 

Robby

[GPRACER]

I think I was supposed to keep you update as I have the same problem. My '95 gp actually had a missfire under the same conditions, had some corrosion on the coil terminals and 2 bad plug wires. I have fixed the missfire but have yet to roadtest the car to see if the problem is fixed. One other thing I discovered is that there is a pcm update/calibration for the torque converter clutch, a reliability issue. If you bring the car to the dealer that should be one of the first things to check. If they have not, ask. Your problem should be fairly easy because the 1996 has obdII and access to a lot of different types of data with the Tech2 scanner. I have obdI not as much info available. I'm also pretty sure that the TCC Solenoid on the 4l60E is in the valve body and you do not have to remove the side cover, just the pan.

 

I am a GM technician at a dealership, unfortunately we are a very specialized shop and I don't get the oportunity to work on many transmissions. Tranny problems automatically go to the transmission department.

[GPRACER]

Also, if it is a torque converter issue the problem will be present in drive as well as overdrive, just at a higher rpm. TCC lockup occurs in both gears.

[harrydunn]

Thanks for the help with the tranny. I'm taking it in Wednesday and hopefully things will work out. I think I may print out your thoughts and take them with me--I'm sure they'll love that! I'll keep you posted. I'm a little baffled now by what you're saying. Mine only seems to be doing it in OD because as soon as I tap the brake and the TC disengages, the RPM's jump up and everything's fine. However, you're saying that if it is the TC, that'll I'll notice it in Drive as well? I sure don't notice it in Drive. Perhaps it is a coil/misfire problem, but the first Chevy dealer exhausted that idea. Who knows. Any last thoughts before I take it in? Thanks a lot.

[GPRACER]

My problem is FIXED!!!

 

It was not tranny related at all, but a missfire(s) as I suspected. did feel like transmission problems though. I had 2 coil terminals corroded, caused some carbon tracking on the wires and plugs, I cleaned up the terminals on the coils and re road tested, but the problem was still there, ended up replacing the 2 coils, 2 wires and 2 plugs. Funny, there was only 20k on the plugs and wires. I guess the weak spark from the coils damaged the plugs and wires. Resistance on the 2 wires was in the 40k ohm range, much too high.

 

Anyway's it was a little harder to diagnose with the obdI system, Keep us posted on yours.

[harrydunn]

That's great that you got yours fixed. I'm sure that's a big load off. Mine, however is most definitely the tranny shudder problem many experience. Had it and the dealer Wednesday and took the GM mechanic for a ride. He felt what I was talking about. Unfortunately however, it's not throwing a code yet so they won't dig into it. That's pretty much what I figured. He took me aside away from his service manager and gave me the name of a friend with a tranny shop who will do the Sonnax kit fix fairly cheap. He said it was most likely getting ready to throw the P1870 code. He had the same problem on a similar car of his own and had his friend put the kit in it. On the positive side, they did replace under warranty the air bag module ($800 part on recall!), fuel pump, belt tensioner, leaky lower intake gasket, and I slapped a new set of plug wires on it, so it is definitely not the same misfire problem as yours. I think I've got it cornered as a torque converter problem. So, to sum it up I've got to pay $196 ($100 which is deductible, rest is fluids, etc.) for $1493 worth of fixes. Not too bad I suppose. I'm going to post a new topic soon and try to get some feedback about the Sonnax kit fix if you want to chime in on that one. My warranty is up in 6,000 miles so I think I will at least drive it until then and then decide what to do. Thanks for your help. I'll try to get that other post up soon.

[Guest Anonymous]

$800 for the airbag module? WOW!

[harrydunn]

Yep, Drivers side inflator module per recall. They accidentally charged me for it too! I got that taken care of quickly however.

[Guest Anonymous]

Yep, Drivers side inflator module per recall. They accidentally charged me for it too! I got that taken care of quickly however.

 

That would be an expensive accident!

[92euro]

I seem to have a problem with my tranny also, sometimes when it's cold my car will rev to about 2500 and then slam into gear from a stop. Sometimes I'll catch it and let off the throttle and it will just seem to snap into gear. I've also noticed hard shifts occasionally but it's a once a day thing, usually happening after whatever redlight or stop sign I end up at first.