I had the transmission fully serviced less than two years ago. This past Feb, the pan gasket appeared to be leaking. I had it replaced a week ago and I believe it is leaking again. I am investigating by wrapping certain areas on the trans with paper towel pieces to determine if the leak has another source. I had the selector shaft seal replaced a year ago so I am checking that also. The service manual states that the pan s/b torqued at 144 inch-lbs. The Mitchell's manual say it s/b torqued at 100 inch-lbs. Which is correct???
44 inch pounds is approximately the fart from tinker bell. (Four ft-lbs)I would go with the higher number. The pan always gets blamed for transmission leaks. You are on the right track to keep looking.
Without digging out a service manual, I found this online. 9 lbs/ft (108 lbs/in) seems in line with what I recall from my dealership days. https://www.gmtransmissionparts.com/4l60e-torque-specs/
With the inspection cover off, and with car up on jack stands, their is no leaking from the front of the tranny. Dry as a bone. I determined that the pan gasket is not leaking. That problem is solved. I had the pan gasket replaced as it was over torqued. Gasket was cracked & crushed at the front. However, I ran a swab about the selector gear & found trans fluid on the swab. The selector shaft seal was replaced a year ago & now I believe this is a second source. I think the mechanic may have damaged the seal when installing it, over the front &/or back ridge of the shaft. I watched a mechanic r/r the seal, on youtube. I have placed the car back on the ground & will drive it & verify the leaking. Will let u know. Tkx guys.
Ive started running those morso blue metal core gaskets as pan gaskets from now on as those seal so much better and wont crush or distort.
The moroso gaskets are nice...but 98% of the time the issue is the pan rail flange....it will bulged around every bolt hole from it pulling the aluminum....I take a razor blade and drag it across the flange...this will do two things...smooth out minor surface imperfections and show you where bigger issues are that will require a file....you get the flange flat and your issues are over
