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Short-term emergency(like)... 4*E*AT - Transmission *not* dead?...


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Hi,

Gotta make a command decision (on, it seems, half a brain and no computer-car experience!...) tonight!

 

96 OBW 2.5 automatic, just got it in June 06, 111k. (Sube *and* computer car virgin) Just after timing belt in late August, transmission started to slip a bit... took it in, rebuild, $4-5k, yada... Noslip helped some, its slowly slipping more (seems like 3rd gear mostly). Today wasnt sure if I'd even get to work.. Been searching for used 4EAT...

 

Also, the passenger side valves starting clattering a week ago, esp. cold, idle, ... (now in Day 2 of MMO in crankcase, some better, may try SeaFoam over the weekend). Also the cars been starting to idle a bit rough... So just for the hell of it today, @ lunch, yanked the battery cable, ~3hrs, to see what would happen.....

 

Drive home was like driving a new car!!!!

 

No Slip, couldnt make it slip!.. Also shifted smooth, (up and down) strong and had great power and acceleration! WTF!!!:confused:

 

Heres the deal: have already paid for a used tranny ($250\61k), have a rental car to go pick up with in PA on Saturday and have a shop on hold to swap it in on Monday ($450).

 

So:

 

- Problem was obviously Electronic (not the tranny itself, at least originally)

- I've been clearly slipping the hell out of it for the past ~3months\5k miles.. probably cooked it good

- Never had CEL come on (looked for codes tonight, after reset, nada.. duh..)

- Have no idea of what made it start slipping in the first place

- Assuming its electronic, (my v. slim knowledge base so far)

Main Computer itself

TCU (?)

Stuff internal to the tranny (solenoids, connectors, etc...)

 

Could swapping the tranny also swap possible (internal\E) culprits?

 

Since I've clearly shortened the trans life, although its running better, would the swap make a sense or just waste $700 leaving me to find the actual problem!?!

 

Thoughts\Opinions much appreciated?:-\

 

-John

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If the existing tranny was actually slipping as much as you said for that long you probably wore off not a trivial amount of clutch material. So anyway, if you already paid for/committed another transmission you really have no choice but to follow through. Maybe you don't have to install it right away if there don't seem to be any issues at the moment but AT slipping=not good.

 

Typically if the TCU detects any slippage it will crank up the line pressure to the max to try to prevent the slipping which may also result in harsher shifts. If it still slips at max line pressure that then that's not good.

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I think I'd just hang on to the spare transmission and run the

original one till it dies. Hopefully it'll give some warning before it

quits and you'll have a spare. If you don't keep the spare you

are sure to need it and if you keep it you'll never need it....or

so goes my luck.

 

Richard

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I guess my question is:

 

If resetting the computer changed how the transmission shifts now, what threw it out of whack in the first place and could swapping the tranny now (potentially) replace whatever caused it, or could I just end up with a new\used tranny and some faulty electronic\computer issues still waiting to be diagnosed?

 

Could the TCU be the culprit? How hard to swap? (seems like its pretty cheap).

 

Since I've never had the CEL come on, could the tranny have been returning codes (that I never checked?) or are codes only displayed with the CEL being illuminated (again sorry, before this my most current car was a 91' Honda!).

 

 

If the existing tranny was actually slipping as much as you said for that long you probably wore off not a trivial amount of clutch material. So anyway, if you already paid for/committed another transmission you really have no choice but to follow through. Maybe you don't have to install it right away if there don't seem to be any issues at the moment but AT slipping=not good.

 

Typically if the TCU detects any slippage it will crank up the line pressure to the max to try to prevent the slipping which may also result in harsher shifts. If it still slips at max line pressure that then that's not good.

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Yeah,

Gotcha there....

 

It was only $250 and thatd be cheap insurance (It I *didnt* have one I *know* it'd die!).

 

 

 

 

 

I think I'd just hang on to the spare transmission and run the

original one till it dies. Hopefully it'll give some warning before it

quits and you'll have a spare. If you don't keep the spare you

are sure to need it and if you keep it you'll never need it....or

so goes my luck.

 

Richard

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Hi

 

Yes... have been checking in between oil changes, which I've been pretty regular @ 3k...

 

As to what they've been putting in, I have to assume that they have that much on the ball.

 

I do have a quart of Lucas No-slip in there, and, other than refilling after the TB, (Dexron III) havent had to add any.

 

 

 

Perhaps a dum question, but your fluid level and quality is good in the current AT? Someone didn't put the wrong ATF in it before like I don't know maybe for some other Japanese make that might have more heavily friction modified fluid than Dexron III?
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Give it a month, the slipping will return. You reset the computer, so the car went back to default values. This is harder shift (you may not notice). If it was slipping as bad as you say, then significant damage has been done. Pickup the trannyy, your going to need it.

 

 

nipper

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Roger that...

 

Will use the time to do the oil pump...

 

(any experience with checking oil pressure?..... putting the pieces together, I am guessing that I may not have got the "O" ring on right when I reseated the oil pump during the TB change... noticed valve click right away... coming and going... now the right side valve are pretty loud... figuring either worn\weary\poorly seated oil pump or some gunk in an oil channel...). Marvel Mystery seems to be having some effect (will run Seafoam over the weekend), next step, will replace the oil pump..

 

 

Give it a month, the slipping will return. You reset the computer, so the car went back to default values. This is harder shift (you may not notice). If it was slipping as bad as you say, then significant damage has been done. Pickup the trannyy, your going to need it.

 

 

nipper

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since he sent me an email and asked me to post i'll agree with what's been said. get the used transmission and hold on to it until problems return. $250 is a good deal and low mileage as well, and i'd be surprised if it doesn't start slipping again in the future.

 

i've heard that electric signals can get fuzzy and components can work better after battery disconnects. doesn't happen often, but it does. disconnecting the battery and also running new ground wires (on the engine) are typical electrical clean up *tricks*. the exact cause and prevention i don't know.

 

transmissions can be very resilient, i'd be tempted to keep driving your existing trans until the problem comes back. but this is coming from the guy that had to drive in 2nd gear from kentucky to maryland...it took about 16 hours i think. that sucked, but i got home and swapped transmissions so all was good! i knew my trans had issues but it was winter and i didn't feel like dealing with it then.

 

good luck!

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Here's an electronic trick for yah.

Take some 10 gauge wire, slap one end of that puppy on the negitive terminal of your battery, and take the other end, and slap that mofo onto your engine block (un bolt something, & bolt it on w/ a ring terminal, battery & block of course).

That's made a world of difference in shifting w/ my 4eat

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Heres yet another aspect that is really cooking my noodle...

 

My torque bind is also gone!... turns as smooth and effortlessly as I've ever driven it....

 

Go figure...

 

Will head down and pick up the unit tomorrow....

 

Thanks... appreciate it...

 

 

since he sent me an email and asked me to post i'll agree with what's been said. get the used transmission and hold on to it until problems return. $250 is a good deal and low mileage as well, and i'd be surprised if it doesn't start slipping again in the future.

 

i've heard that electric signals can get fuzzy and components can work better after battery disconnects. doesn't happen often, but it does. disconnecting the battery and also running new ground wires (on the engine) are typical electrical clean up *tricks*. the exact cause and prevention i don't know.

 

transmissions can be very resilient, i'd be tempted to keep driving your existing trans until the problem comes back. but this is coming from the guy that had to drive in 2nd gear from kentucky to maryland...it took about 16 hours i think. that sucked, but i got home and swapped transmissions so all was good! i knew my trans had issues but it was winter and i didn't feel like dealing with it then.

 

good luck!

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