Coolant puddle under transmission
 

I have a 94 LT1 and for the last 6 months I have been noticing a small puddle of coolant under the transmission when I start it. I found that the coolant is coming out of the small hole in the middle of the flywheel cover at the very bottom. The coolant comes out for the first couple of minutes then stops. (it looks like it collects overnight)

I checked the cooling lines going into the transmission on the passenger side and both are tight. Has anyone seen this problem before? I checked the FSM and it appears that the cooling lines go into the transmission oil pump. Does anyone know if there are replaceable seals on the pump that could be causing this?

If anyone has seen this can you tell me what kind of repair bill I am looking at? I know the transmission has to come out if it is an internal seal.

Thanks

If it is coming from the back of the block and not trickling there from an intake (or other) leak, it could be the freeze plugs in the block. $1 part that adds $300 labor to it. I would suggest a pressure test to be absolutely sure it is what you suspect, before pulling out the trans.

Thanks very much for the suggestion - a pressure test would make sense before going any further.

I will crawl under and see if I can see anything around the freeze plugs as well.

Thanks again

Yes, it has to be one of the core plugs in the rear of the block to be running out of there. The intake on an LT1 has no coolant passages and the banjo fittings at the rear of the heads could be the only other remote possibility I can think of. Your cooling lines BTW, carry transmission fluid to the radiator for cooling, not antifreeze to the transmission. As Pete said, a simple pressure test should pin-point the source and you're in all probability looking at a transmission R&R to make the repair. There are two back there so change them both. Actually it'd be a good idea to replace all of the core plugs in the block because rust has decayed them. This has been caused by a lack of proper cooling system maintenance over the years.

Also, if the trans does have to come down, I recommend changing all of the external seals. $20 worth of parts and an hour or less will change them all. No one likes a drippy vette:cheers: