When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Gearbox has probably never been out at 110k miles. I'm refreshing the drivetrain, and would like to solve the mystery oil leak which seems to originate from top of the gearbox. Is all of the oil caused by the transmission vent? I'm tracking the car, so I expect the oil to run hot and expand. Could it be an idea to put a hose on the vent, which drops the oil underneath the transmission instead?
I wouldn’t necessarily call that a leak however I’d wager it is coming from the trans and diff vents. When my diff first discharged gear lube after some spirited driving I fabbed an extension by removing the diff vent cap, ball and spring and installing, IIRC, a 12” or so 3/16” rubber fuel hose. I placed a new vent in the open end and secured it above the diff. Never had another problem. I would assume the same could be applied to the trans. At 110k miles, if yours wasn’t actually dripping lube that accumulation on the trans and diff are pretty much normal IMO.
Oil leaks in a scenario like yours will be difficult to locate. Oil creeps so much it can be very misleading. The good news is spray that down with some good degreaser (I'm a fan of "SuperClean" in the purple bottle) and pressure wash it. There are so few areas for these to leak it won't take you any time to reseal any suspect areas. I wouldn't be concerned with relocating the vent. I've been tracking my car for years without issue.
I did have what I thought was a leak (RPM Level 6) on my trans. I thought it was from the rear housing. It was just the fill plug wasn't tight enough.
What is your plan wrt "refreshing"? I have some suggestions if you track the car.
Best of luck!
Thanks for the input. When parking the car it would always mark its territory - drops of oil on the floor, coming from the joint between the transmission and the differential. I'm hoping to get rid of that.
I'm installing a rebuilt differential, 4.10 ratio, new seals, C6 Z06 internals. Also replacing the clutch, flywheel, slave cylinder and rebuilding the torque tube.
The new diff comes with its own new input seal, but how about the T56 output shaft / rear seal? Is that a seal recommended to replace?
Gearbox has probably never been out at 110k miles. I'm refreshing the drivetrain, and would like to solve the mystery oil leak which seems to originate from top of the gearbox. Is all of the oil caused by the transmission vent? I'm tracking the car, so I expect the oil to run hot and expand. Could it be an idea to put a hose on the vent, which drops the oil underneath the transmission instead?
Thanks for the input. When parking the car it would always mark its territory - drops of oil on the floor, coming from the joint between the transmission and the differential. I'm hoping to get rid of that.
I'm installing a rebuilt differential, 4.10 ratio, new seals, C6 Z06 internals. Also replacing the clutch, flywheel, slave cylinder and rebuilding the torque tube.
The new diff comes with its own new input seal, but how about the T56 output shaft / rear seal? Is that a seal recommended to replace?
If it were me I'd be replacing everything I could get my hands on and rebuilding everything I could afford. Do it once and do it right.
Also there's someone on here selling a Tranzilla T-56/built diff on here somewhere. Might be worth a look.
07-27-2023, 03:34 PM
T56 transmission - oil leak source?
