96 transmission OD problem?

I'm not a mechanic by any means, just do a little basic maintenance now and then.

I have a noise that started maybe a year ago and wonder if it's bad transmission news? Driving at highway speeds in Overdrive, say 50 or above, if I come to a hill, or on the level, and need to accelerate slightly, there will be very little response and there seems to be a vibrating noise, almost like it wants to downshift but won't. I can either punch the gas pedal down a little and it will downshift, or downshift by moving the gear selector into regular Drive, and it shifts and speeds up normally. If I do neither and just let it go along, it maintains speed but the noise/vibrating sound continues.

I had the trans. fluid changed a few months ago; otherwise the trans. seems to operate fine.

Any ideas what it might be or what I might be in for?

Noise diagnosis is incredibly hard without hearing it; can you describe the noise? Patterns, related to engine/road speed, low-medium-high, can you feel and hear it, etc. The more info the better, but it sounds like the lockup solenoid isn't releasing fully.

Noise diagnosis is incredibly hard without hearing it; can you describe the noise? Patterns, related to engine/road speed, low-medium-high, can you feel and hear it, etc. The more info the better, but it sounds like the lockup solenoid isn't releasing fully.

Yes, I wasn't sure how to describe a noise... I'd say it's sort of a coarse roar, except it's not real loud; also I can feel a sort of slight vibration thru the accelerator pedal until it downshifts. The sound seems identical whether at 50 or 70 mph. I can tell when it's doing it even with the stereo playing, I can feel it in the car's response and resistance to accelerate.

Find the plug for the converter lockup on the transmission and unplug it. Go for a ride and see how it feels. The overdrive will still work, but the transmission will tend to run hotter than it should.

If that does it, you know what the problem is, the lockup switch/solenoid is bad. The one in my '84 Caprice has been unplugged for at least the last 40k miles with no ill effects. The OD works fine, I have to watch my tranny fluid level, it does use about a 1/2 quart every 6 months.

Bob

dont leave that TCC plug unpluged too long. it can burn up your transmission insides and damage the unit. we had a GM tech on here telling us about that some time back.

Yeah, mine's only been unplugged since 1999 or 2000. I'll have to crawl under and plug that baby back in.

I have the same problem with my 1996 lumina. How did you correct the problem?

I have the same problem with my 1996 lumina. How did you correct the problem?

lumina1996,

When this first started, I had the trans. fluid changed and that seemed to help for a while, but it has been gradually getting worse over time. I currently have about 138,000 miles on the car. The Service Engine Soon light has come on occasionally, sometimes for a couple days at a time, and then turns itself off too. This doesn't happen very often, but I've wondered if it's related. Maybe, maybe not.

I haven't done anything yet, I'm still checking into it.

Please post back if you find anything out.

Thanks.

If I recall correctly, the later-model 4T60E transaxles have a single plug from the PCM to the trans, hence preventing you from disconnecting just the TCC solenoid without cutting wires. If it is the TCC then you can have fun tearing up the driver's side and swapping out the solenoid yourself, or give the transaxle a shot of TransTune or TransX, then change the fluid and filter. I'd give the additive a try first, since the two I mentioned are usually the only ones that actually -do- anything...

This thread has a couple relevant statements to one of the issues I have with my '96 Lumina 3.1L.

I have had a Check Engine Soon light for years - literally - and its code claims my 2nd gear solenoid is bad.

The ONLY symptom of this bad solenoid - in my situation - is after spirited, lengthy highway driving the tranny won't downshift into 2nd if I have any throttle applied, but coasting or braking to a stop, it does so without a problem.

Anyways, it *sounds* as if replacing a solenoid is a lot of work. I am unskilled in fixing my car so the above-described task list looks quite daunting to me.

Does anyone know of any resource that would step someone through the process of changing that though?

Also, to the TransTune-promoter of sorts: are you recommending TransTune/TransX for someone with a known solenoid issue as well? If so, could you please explain to me what an additive would do to help a faulty solenoid? I'm ignorant of such things.

No additive can cure a mechanical /electrical problem in the trans. It really should be scanned with a trans capable scanner to confirm solenoid operation, if it turns out to be bad the pan comes off, circuits are rechecked and the solenoid can be replaced at that time.

No additive can cure a mechanical /electrical problem in the trans. It really should be scanned with a trans capable scanner to confirm solenoid operation, if it turns out to be bad the pan comes off, circuits are rechecked and the solenoid can be replaced at that time.

Your first statement affirms my gut feeling on the subject. I'm not sure in what context the other fella was recommending TransTune/TransX within: that's why I wanted to verify. Thank you.

Only the pan needs to be removed to gain access to a solenoid? I have NO clue with this sort of thing, though a I have two great shadetree mechanic friends, and I am trying to figure out if this is something I'm gonna have to shell out the dough for, or if it's something a long Saturday afternoon of swearing and sweating will cure. :)

And if anyone thinks that someone like myself should just shell out the cash, could you provide an educated opinion on time for labor please?

No additive can cure a mechanical /electrical problem in the trans. It really should be scanned with a trans capable scanner to confirm solenoid operation, if it turns out to be bad the pan comes off, circuits are rechecked and the solenoid can be replaced at that time.

I have a 93 lumina with similar transmission problems. I bought a new TCC solenoid and removed the pan but where exactly is the TCC solenoid located?

Solenoid is in the side cover not the lower pan. Thsi may not be a "dyer" type job, access may require dropping the sub frame. The shift solenoids are in the lower pan, get this diagnosed properly before replacing anything here.

Solenoid is in the side cover not the lower pan. Thsi may not be a "dyer" type job, access may require dropping the sub frame. The shift solenoids are in the lower pan, get this diagnosed properly before replacing anything here.

My SES OBDII code is allegedly (second-hand info I'm relaying) 2nd Gear Shift Solenoid...you're saying just removing the lower pan makes it accessible?

Where could I/we find any instructions on how to replace these solenoids?