Everything is new and when I built it i followed directions to a T especially with rear main. ðŸ˜I would say more likely main seal. Check out the pic on my 170k mile 5.3 in my truck in post #1. I replaced the seal and leak fixed.
Texas82GP's GMT900
A little less than two weeks ago the transmission went out on my daily driver. It's a 2008 GMC Sierra 1500, regular cab, short bed, two-wheel drive with a 5.3 and a 4L65E transmission. The 4L65E has been built twice in the last 50k miles. It has some nice goodies inside it but I keep finding...gbodyforum.com
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