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automatic trans question?

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Old Jun 9, 2007 | 11:26 PM
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I bought a 93 last week, and I'm noticing something about the trans that seems weird.

It shifts firm and at the right rpm's, downshifts on demand, and goes into gear without delay, but...

There is NO engine braking. I can take my foot off the gas and pull her to first at 30 and feel nothing, the motor just goes to idle. If I get back on the throttle, the r's come up, and when the motor is spinning faster than the driveshaft she immediately starts to pull, and is definitely in first. Take my foot off the gas, idle.

I've had 2 LT1 C4's previous, back when they were new, I don't remmeber this as normal. Is it?
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Old Jun 10, 2007 | 09:37 AM
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Originally Posted by JimMel
I bought a 93 last week, and I'm noticing something about the trans that seems weird.

It shifts firm and at the right rpm's, downshifts on demand, and goes into gear without delay, but...

There is NO engine braking. I can take my foot off the gas and pull her to first at 30 and feel nothing, the motor just goes to idle. If I get back on the throttle, the r's come up, and when the motor is spinning faster than the driveshaft she immediately starts to pull, and is definitely in first. Take my foot off the gas, idle.

I've had 2 LT1 C4's previous, back when they were new, I don't remmeber this as normal. Is it?
Not normal at all.
I would suspect a seal failure on one of the 2 overrun piston lip seals.A bad teflon input shaft seal may also be contibuting. Also a worn rear stator bushing could contribute as well. Should be easy to find when it is apart.
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Old Jun 10, 2007 | 11:27 AM
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Thanks for the info. Makes sense.

How's your crystall ball Pete?

I just bought this car a week ago. It's waranteed 50/50 for 30 days. I'll have to pay half of any repairs.

Is this trans gonna fail?
Or just continue to not engine brake when I manually downshift?
Could this type of problem result from anything else? An improperly installed shift kit possibly?

What would you (or any other readers) do in my position?
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Old Jun 10, 2007 | 11:34 AM
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Originally Posted by JimMel
Thanks for the info. Makes sense.

How's your crystall ball Pete?

I just bought this car a week ago. It's waranteed 50/50 for 30 days. I'll have to pay half of any repairs.

Is this trans gonna fail?
Or just continue to not engine brake when I manually downshift?
Could this type of problem result from anything else? An improperly installed shift kit possibly?

What would you (or any other readers) do in my position?
Usually heat and age harden fragile rubber lip seals. If my guess is correct, you were very fortunate to have the overrun seal fail. 14 years is enough time for this to happen. Even on a lo mile, well maintained car. If it happened to any other clutchpack, you would not be driving the car. Again, if my crystal ball is correct, others will fail shortly. In my opinion, symptoms are sufficient to make a warrantee claim. Be absolutely sure to flush the trans cooler and remanufacture the stock converter. Pay for this out of your pocket if nescessary. You must do both to guarantee a long life rebuild.
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Old Jun 10, 2007 | 11:36 AM
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Originally Posted by JimMel
Thanks for the info. Makes sense.



What would you (or any other readers) do in my position?
I would absolutely rebuild it. Easy for me to say though, I do them myself.
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Old Jun 10, 2007 | 04:02 PM
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Another test drive (paying max attention this time) shows I have normal engine braking in reverse, but not in any forward gear.

Pete, thanks for your replies. I think monday I'll have it checked out by a trans shop, then take that and your replies back to the dealer.
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