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92lxsleeper
05-03-2008, 01:15 AM
1988 celebrity
2.8L MPFI
3 speed automatic


ok so i've been leaking tranny fluid slowly ever since i got the car.

went for a drive today and after a while, on the return trip i stopped at a red light. and the car stalled... "like stopping a 5 speed without a clutch"

i started it back up and it died again. the only way i got it going was to start it in neutral, and drop it in low at 3500 rpms and floor it.

i got it back to my yard and stalled. i checked the tranny fluid and the stick had only a little fluid on it (prolly spray)

but after a while i started it up and it was fine.

does anyone have a clue on what is wrong? is it just because its low on tranny fluid?

or is there a converter lock up solenoid that i can unplug? (possibly that electrical plug on the front of the tranny under where the air intake is.

Techfizzle
05-03-2008, 01:31 AM
this has been talked about beforehttp://www.mysmiley.net/imgs/smile/tongue/tongue0011.gif its more than likely your torque converter http://www.mysmiley.net/imgs/smile/sad/sad0025.gif.
Unpluging it will cause bad gas mileage http://www.mysmiley.net/imgs/smile/scared/scared0008.gif so i would fix it. you should check your tranny fluid while its running http://www.mysmiley.net/imgs/smile/cool/cool0036.gif

92lxsleeper
05-03-2008, 01:42 AM
how much does a TCC solenoid cost? and how hard is it to change it out? could u give detailed steps? i've never had a GM car before.

im used to mustangs AOD, and A4LD automatics.

LordDurock
05-03-2008, 01:45 AM
well frist you trany fuild should be on the stick at lest...............could be lowe trany fuild.
after you get you fuild lever right. see what it does. if not you convert could be seized. requiringe a replace ment...............i have a converter off a 125c i could send you.

the more i think about this the more it soulds like a seized conveter

Tonglebeak
05-03-2008, 01:50 AM
He says it starts up fine after letting it sit. It's the same story as anyone else (including myself) who had this problem.

Yes, you can unhook the TCC harness on the front of the tranny. You won't really see bad gas mileage. When the TCC's engaged, It'll drop RPMs by around 250 so you'll probably lose 1-2mpg but that's a much better option than stalling in traffic.

I had taken mine to AAMCO long before I knew jack shit about cars. They replaced it and did a full tranny flush for $400...anyways, the solenoid was only $21 according to the bill. Someone has a step-by-step procedure on replacing it from the left wheel well. Jr3800 I think?

92lxsleeper
05-03-2008, 02:03 AM
yea it kinda scared the crap outta me, everytime i put it in gear it stalled... and i was in the middle of an intersection too XD.

good thing a cop wasn't behind me when i lit the wheels up :P

Techfizzle
05-03-2008, 02:17 AM
$400 for a trany flush?!?! you got a robbed. coulda done it yourself for $20

92lxsleeper
05-03-2008, 02:20 AM
http://www.cardomain.com/ride/3067334

thats the celeb if anyone is intrested in seeing it...

Tonglebeak
05-03-2008, 02:49 AM
$400 to do a tranny flush and replace the solenoid, not just the flush itself -_-

85_Ciera_Rebuild
05-03-2008, 02:58 AM
Yes, you can unhook the TCC harness on the front of the tranny. You won't really see bad gas mileage.

If you are traveling at less than around 35 miles per hour...there will be no change in fuel economy.

But, at higher speeds, there will be transmission slippage via Torque Converter, which could cost you more fuel burn....I would estimate up to 4 mpg or more...it all depends upon if traveling on a flat road versus hilly terrain...if wind is blowing....and at rate of speed traveled...the higher the speed, more fuel lost to not have a TC.

My 1984 Volvo has an automatic with an overdrive, but it does not have a lockup torque converter; overall, I think it cost up to 6 mpg lost, when higher horsepower is required during driving.

Tonglebeak
05-03-2008, 03:51 AM
The lockup only kicks RPMs down by about 250. You're not going to lose more than a couple miles unless you have other issues, although I will admit there is a noticeable power increase when lockup engages (speed will hold steady in 3rd, then when lockup kicks in car accelerates).

But in any case, until he replaces the solenoid, unhooking it will be the safest option despite some gas costs that willl certainly come with it.

LordDurock
05-03-2008, 04:05 AM
shouldnt the lock up dessange when the car stalls though? this sounds more like a Tc problem then aTCC problem.........just me

Tonglebeak
05-03-2008, 04:06 AM
That's the thing, the lockup solenoid itself is bad, so no, it won't disengage until it cools down and "unsticks."

Tuddi
05-03-2008, 06:42 AM
That damn TCC is a timebomb that is out to kill the people in the car.

Unplug the bastard until you get to change it. Mine did exactly what you are describing, and I was terrified of driving the car in "D".... so I had it in second gear after the first couple of miles driven... or it would simpy lock up and block traffic.

Pull the plug on it and be safe.

Jimbo
05-03-2008, 03:21 PM
Based on what I've read and what people say on these forums, like 75% of all 125c transmissions have this lousy problem. I also can't imagine having the "lesser" transmission available with the 2.8, I've always been used to the larger lockup and lower engine RPMs at higher speeds with the 440 :)

Anyway, how often do you drive your car? If it's an every day user like mine is *points to avatar*, then pay the money to fix it and avoid problems like this for the rest of the car's lifetime; otherwise it may just be worth unplugging it and calling it a day...

Buick_powa
05-03-2008, 04:40 PM
Based on what I've read and what people say on these forums, like 75% of all 125c transmissions have this lousy problem. I also can't imagine having the "lesser" transmission available with the 2.8, I've always been used to the larger lockup and lower engine RPMs at higher speeds with the 440 :)

Anyway, how often do you drive your car? If it's an every day user like mine is *points to avatar*, then pay the money to fix it and avoid problems like this for the rest of the car's lifetime; otherwise it may just be worth unplugging it and calling it a day...

440 is THE slush box to have on any A body!

86euro
05-03-2008, 05:45 PM
Just unplug it and leave it at that. It won't affect the milage enough to matter, and you won't have to worry about it failing again.

Pontiac6ksteawd
05-03-2008, 06:28 PM
Someone say write up??

http://www.kichline.com/chuck/fiero/TCC.htm

Althou the link is for a Fiero, it directly applies to us too with the 3 speed tranny. The job takes about 1 hour. And I will also completely disagree with 86Euro. Without the TCC, the tranny temps run about 20-30 degrees hotter. Heat is what kills a tranny. I have seen these trannys go along time without the TCC solenoid, but I would replace it to be on the safe side. Parts are about 50 bucks. And your problems are indicative of a faulty TCC solenoid, and not the Converter itself.

Jimbo
05-03-2008, 06:39 PM
440 is THE slush box to have on any A body!

What! You're out of your mind! 440s were always the premier transmission of A-body's and they've never had a single issue throughout the 5 I can remember my family owning throughout the years, including my recent 2 I've owned. Stronger tranny, plus lower RPMs = your logic is insane? :p

Pontiac6ksteawd
05-03-2008, 07:37 PM
What! You're out of your mind! 440s were always the premier transmission of A-body's and they've never had a single issue throughout the 5 I can remember my family owning throughout the years, including my recent 2 I've owned. Stronger tranny, plus lower RPMs = your logic is insane? :p

Where are you getting your info from? The only benefits to a 4 speed tranny is fuel milage. They are a weaker tranny until they tranny was revamped in the middle 90's to the 4T60E, you havent had a single issue yet, but you will soon. Those trannys couldnt hold the meager 210 HP put out by the TGP and the 3.4DOHC Engines, in 3.8 platform, as long as you maintain them, you can make it to the mid 100k mile range.

Now on the other hand, the 3T40 In our A-bodys, referred to as the 125C, has been proven to be almost bullet proof. With them being put into the Fieros, with engines that have some 400 HP, and going strong, or for the everyday user like us, that have put them up to close to the 300K mile range stock.

Now this isnt saying the the 4T40 couldnt be a good tranny if built up proper, cause it can be done, with hardened internals, better bands, modified valve body, and a few other things, the 4T40 can be a good tranny, but never as good as a 3T40/125C

86euro
05-03-2008, 07:44 PM
Althou the link is for a Fiero, it directly applies to us too with the 3 speed tranny. The job takes about 1 hour. And I will also completely disagree with 86Euro. Without the TCC, the tranny temps run about 20-30 degrees hotter. Heat is what kills a tranny. I have seen these trannys go along time without the TCC solenoid, but I would replace it to be on the safe side. Parts are about 50 bucks. And your problems are indicative of a faulty TCC solenoid, and not the Converter itself.

To each their own:cheers: I do realize the tranny will run a little hotter, but being only a three speed, the car will be running a good bit higher rpm than max stall at freeway speeds, so it shouldn't be an issue (IMHO). I have put 60-70K on these things without the lockup, problem-free. Look at it this way, when's the last time you herd someone say their turbo350 died because it was made before lockup convertors came into play?

Pontiac6ksteawd
05-03-2008, 07:52 PM
Also remember that the repair will pay for itself in 13 fill ups, at 10 gallons a peice, at a rate of roughly 3.80 s gallon. That is if you do the repair yourself.

Zaloryan
05-03-2008, 09:02 PM
I replaced the TCC solenoid on my 3T40 a week or two ago. It ws a simply matter of pulling the driver front wheel off. Then you pull the side cover off the transmission. It's metric, 13mm. You'll have to worm the cover off around the frame rail. The solenoid on my transmission was on the bottom of the transmission where the side cover is. I thoroughly wiped my wrenches when I got into the transmission so I got the utmost minimal dirt into the tranny. There's a torx screw holding the solenoid into the tranny. You also have to disconnect the two wires leading from the solenoid. (By the way, my solenoid cost about $30 at O'Reilly's) The connectors screw on to each other, and don't plug in. When I went to O'Reilly's, they had several different solenoids listed for my transmission, but they were all under the exact same part number! Make sure you physically match the solenoid to yours off your car. After I got it all back on, I went on and replaced my transmission filter and fluid. When you pull the side cover off, you might want to put the jack stand on your driver side 1 notch higher so the fluid doesn't spill everywhere when you pull the side cover off.

Just my $0.02. Hope it helps.

-Mitch

92lxsleeper
05-03-2008, 10:31 PM
well i think with that being the only problem, i'm doing allright.

only 98K miles on the car so i'm doing good.

i don't wanna fix the TCC solenoid, cause i'm planning a 5 speed swap. maybe something cool eventually like a cobalt ss motor or something in the future.

anyone have any ideas for a crazy project for after i'm out of college?

LordDurock
05-03-2008, 11:58 PM
well i think with that being the only problem, i'm doing allright.

only 98K miles on the car so i'm doing good.

i don't wanna fix the TCC solenoid, cause i'm planning a 5 speed swap. maybe something cool eventually like a cobalt ss motor or something in the future.

anyone have any ideas for a crazy project for after i'm out of college?

BLOWER out the top of the hood sticking side ways as part of the twin charge set up ;)

Jimbo
05-04-2008, 12:30 AM
I know you shouldn't believe everything you hear, but this is from Wiki:


A 4-speed version of the 125 was created for the 1985/1986 GM C platform (FWD)/GM H platform (FWD) cars, the Turbo-Hydramatic 440-T4. Many parts were identical to the 125, though it was generally stronger and included an overdrive fourth gear. This transmission was first used in GM's 1985 Buick Park Avenue, Oldsmobile 98, and Cadillac Deville.

That, coupled with my incredible luck with them, coupled with no one else ever bitching about them, makes me think they're the way to go. Oh well, we all have our opinions I guess. The 440 doesn't have that lousy solenoid problem either.

Tuddi
05-04-2008, 01:48 AM
The problem the TCC solenoid presents when it fails, is so serious, that it should have resulted in a recall of all cars that were made with it, and have it replaced with a solenoid that would never ever fail.

Techfizzle
05-04-2008, 02:44 AM
many a bad things have never been recalled to late to issue one.

85_Ciera_Rebuild
05-05-2008, 01:01 AM
The lockup only kicks RPMs down by about 250. You're not going to lose more than a couple miles unless you have other issues...

If driving on flatground under say 33 mph, just below where vehicle's locks up, you can get 30 mpg without lockup engaged on my 88 Beretta.

I could quickly find out more specifics if I pulled the TC plug...but my point in the other post is that with higher horsepower requirements, your mpg will decrease accordingly.

85_Ciera_Rebuild
05-05-2008, 01:03 AM
TCC solenoid presents when it fails, is so serious, that it should have resulted in a recall of all cars that were made with it..

Shops made a ton of money off of those vehicles...tons.

There may have been a recall, but it may have been one of those were the customer has know about it....

Jr's3800
05-05-2008, 09:10 PM
I don't have any step by step instructions for the TCC Solenoid replacement.. But the Solenoid is pretty cheap... Just takes a little to gain access to it.. And when the solenoid malfunctions it will be just like a Stick shift that won't allow you to release the clutch..

I will say Unplug the Trans Connector and see if the TCC stays unlocked..

The THM125c( 3T40 ) are known to have this issue during ownership.. Very common... Keep in mind that when the Trans doesn't lock up at speed you are in reality causing the trans to get hot and in some cases any extended driving you do can and will overheat the trans...

But to boot around town you can unplug the Connector..

For others that are listening.... Do not do this with a THM440-T4( 4 Speed Transaxle )... This will severely overheat this trans and in a lot of cases I have seen people burn them up... On this trans it would be very important to have this issue repaired...

Good Luck and let us know what you find..

85_Ciera_Rebuild
05-06-2008, 02:34 AM
I don't have any step by step instructions for the TCC Solenoid replacement..

THM 125C Torque Converter Clutch Solenoid Replacement.
turbokinetic (http://www.a-body.net/forums/showthread.php?t=344)

Jimbo
05-06-2008, 03:15 AM
I had mine unplugged on my 440T4 for 3 months with no consequence whatsoever, then again that was in the sub-zero temps that this Wisconsin's winter yielded. My TCC works fine now after I popped in a new ECM, but still.