The Stovebolt Site Forums The Shop Area Driveline 36 GMC Restoration - 160 oil

My maintinance manual calls for 160 oil for trans and differental.
It is not available anymore and I would like to know if anyone can narrow down what is out there that is comparable. When I search online I get a headach trying to sort out all the options.
I tried 75-140w but it leaks and does not seem thick enough.

I have seen some discussion about hypoid oil is not being good for the really early transmissions. I have also seen the opposite opinion given. Lucos (spelling?) has some great products for the older transmisions.

Thank you for your reply. I got some Lucas stabilizer from Napa today. Put in one quart and topped off with 85-140 as per Napa dealer. It helped to quiet the trans down and did not leak.
Trans still a bit noisy in neutral with clutch out. This may be normal but I have not heard another truck yet. I may have to remove and check bearings. Thanks again , Mike