Why Is Water In My Transmission

[jagerman316]

i had purchased and paid for a local chevy dealer to install a 4l80e tranny in my 98 yukon 13 months ago here recently it started gettin vibrations in high gear only i took it to the dealer and was told it has waster in it and is not coverd by the new transmission warranty and then they said they had no idea what caused water to get in there in the first place now noone has touch the truck since the tranny install ive not been in any really high water and no signs that the radiator is leaking truck is running like a top and has been xcept the vibration in high please help

[Zembonez]

Only time I've ever actually seen water in an auto trans, there was a leak in the radiator cooler that allowed coolant under pressure in through the cooler hose...

 

I'm sure stalling in or driving through really deep water could do it too.

[97SierraGMC]

see where the vent is..

 

i know on a 700R4 they are really little like 3 inches long..

 

see where your vent goes that might be it. btw is the tranny junk? or do you just need a fluid change?

[C6Racer]

Yea, unless you drive through lakes for a living then the trans cooler in the radiator definitely has a leak, that is, if the replacement trans didn't have water in it already.