sawdawg

I have a leak from the computer wiring plug on the passenger side of the transmission. Did I

1. Mess up something when I installed the plug?
2. Should there be an o ring or gasket under the plug?
3. Can I fix the leak from the bottom of the transmission or do I have to remove it from the car?
4 Do I have to drop the pan?


HELP

mrvedit

The connector in the trans has an o-ring to prevent leaks. This connector is part of the internal wiring harness. To replace the o-ring:

1. Drop the pan and filter. Unplug the trans.
2. Unscrew the plate holding the pressure control solenoid. One 8mm bolt.
(probably should disconnect the solenoid first.
3. Press the correct size socket over the top of the connector to push in the plastic
pins so that it drops down. IIRC it is a 1-1/4" 12-point socket that does the magic.
4. Replace the o-ring on the connector.
5. Push the connector into the case until it snaps into place.
6. Replace the solenoid, filter and pan.

Vince B

iTrader: (1)

^and your doing this without removing the 1-2 acc housing? Never tried it that way but we probably need to add this. Also I would like to add dawg you should look at the case bore of the plug area to look for corrosion. Personally I would just replace the harness and be done with it. Make sure the bore is nice and clean and you should be fine.

sawdawg

Thanks... I had lunch with my race car friends today and they said the exact same thing. One guy has been an automatic rebuilder for 40 years and agrees with you. I was just looking for a way to keep from getting oily. Did it start leaking because the wrecking yard was rough when they removed it from the vehicle or is this a common problem?

mrvedit

I don't have the experience to answer your question, but I suspect that if the trans is just sitting there the o-ring might dry out and become brittle.

sawdawg

I stopped by the chevy dealer today to get the o ring. You can't just buy the o ring you have to get the whole wiring harness at $250.oo. I'll take it apart first and match the o ring from a NAPA store.

mrvedit

Or try a trans shop. Mine has bags of extra o-rings to chose from and the mechanic should know which it is. IIRC, it is the 1" green one.

Or here for 45 cents:
http://www.transmissionpartsusa.com/...-000035277.htm

Or PM me your address and I will mail you one (but not till Tuesday).

Or, consider a new wiring harness for $33:
http://www.transmissionpartsusa.com/...-00035400a.htm
This includes a new TCC solenoid too.

sawdawg

I pulled the pan and cleaned up the wiring harness, the o ring looked good. Put it all together with no leaks but now I don't have reverse gear. What does the solenoid I removed do and could I have put it back together clocked wrong. There is also the possibility that reverse was never there because this is the first time I tried to put it through all the gears.

Vince B

iTrader: (1)

The internal harness is not that much money trust me when I tell you. 15320476 is the GM harness pt# and just the oring is 12129390. The complete harness will come with all seals just so you know. HTH Vince

mrvedit

The solenoid you removed is the "Pressure control solenoid" which changes the line pressure according to the PCM. (In simple terms, more throttle, more line pressure).
Vince was probably right that the 1/2 accumulator had to be removed too to get the solenoid out. That controls the 1-2 shift.
I cannot think of anything you could have done that would affect Reverse. The electrical system and solenoids are not used for reverse; only the shift linkage. Therefore make sure your shift linkage reaches Park; the first stop then should be Reverse. If you don't have reverse then, I'm afraid it is an internal problem requiring removal and rebuilding. (Unlikely, but a mis-assembled boost valve could cause loss of Reverse.)
Vince: am I missing anything?

sawdawg

I was afraid of that. This is the first time I actually ran the shifter through the gears, the car has been sitting for a while as I finished another project. I jacked it up started the engine in park and then shifted into reverse. I did it by hand under the car. No wheel movement in reverse, the forward gears seem to be alright. Well at least the engine seeems to run good. I guess thats the chance you take with a wrecking yard drivetrain.