CorvetteForum - Chevrolet Corvette Forum Discussion - [ANSWERED] C7 Z06/ZR1 Transmission Fluid on Ground

The original question is here.

Quote:

jvp asked:
A few of the very aggressive track dogs here on the forum have seen issues with the transmission fluid in their Z06s and/or ZR1s sometimes venting out and leaking on the ground. This after some particularly warm or fast sessions on the track. Can you explain what's going on with this and is it expected?

Quote:

Tadge answered:
A good question.... We haven't talked about it much since this is a rare circumstance experienced by very few customers. The short answer is, yes, this is expected behavior.

The transmission has evolved to be a nearly closed and sealed system, practically lubed for life with minimal maintenance needs. When the trans is working hard, the internals heat up and the entrapped air and air/lube mixture expands. We have to provide a vent for excess pressure to escape because internal pressure can dislocate or damage seals that are critical to reliable operation (note: the differential has a similar venting system). When you factor in build variation, fill variation and environmental variables it is easy to see why some transmissions will expel small amounts of air/lube through the vent. This is the transmission's way of finding the optimal level given all the variables. The amount of fluid should be small, wetting the outside of the case and maybe some drips. It should not be puddles on the floor - that could mean a leak which is also very rare. Just because there is no expulsion doesn't mean that the fluid fill is perfect.... Although most people will never have to add fluid to their transmissions, the "aggressive track dogs" you describe in the question must monitor and maintain their fluid fills per our owner's manual instructions.