Ever since I changed to RedLine Synthetic Trans Gear oil, it leaks oil. I thought it might be the Read Transmission Seal so I replaced that, but it still leaks. Anyone else experience this? I'm thinking my only option is just to go back to non-synthetic Gear oil.

 

Did you over fill it somehow?

 

i've had a rear seal not take before, but synthetic or not doesn't seem to make a difference

 

Can you identify where it is leaking from?

Overfilled, did you add the fill plug before the oil stopped dripping out? Was the trans in near level position, or was the car jacked up only from the filling side of the trans?

Try wiping the bottom of the trans clean, place a drip pad (newspaper or a flat piece of cardboard will do) under the car and follow the drip spots to the source of the leak.

I have used synthetics with intermittent leaking problems in only a few transmissions.

If it is overfilled, it could leak from the rear seal. If leaking from the front of the bell housing, you may have a leaky front bearing seal. If leaking from the seals between the transmission cases, re-torque to no more that the shop manual specs. If it continues to leak from between the case joints, applying an external sealer may help, used in moderation... Clean the exterior very well, with a good brake cleaner, and use a good grade of sealer recomended for transmission gaskets.

If it continues to leak, repost your results from the efforts noted above.

John

 

Service done on a lift. Not overfilled. It's a bit hard to trace because the oil runs along the undercarriage and exits near the doors...
It only leaks for a short time after running the car. After that, no leakage until you drive it again.
The leak started after changing to Synthetic. I had to replace the clutch anyway, so I replaced the rear trans seal. Refilled with synthetic, still leaking. I'm tempted to just replace the synthetic with regular gear oil to see if it stops leaking.