Having a hell of a time getting a straight answer on FB groups and my workshop manual is on CD and my computer died so I no longer have a drive to access it. I have 63' Ford wagon, T-86 3-speed with R-10 overdrive and standard rearend. The engine is back in and running but I lost gear oil and need to replace. I believe both the tranny and overdrive unit have separate fill screws. What gear oil should I be using? Please and thanks! Tomorrow having a Dec warmup, want to take it around the block!
I did OK with GL5 80w90 in mine, but these days it's recommended to use something more like GL-3, which you can't really find anywhere...or something for manual transmissions, like Red Line MT90. Rear end can use whatever 80w90 wt oil they sell these days. Good luck
The BW overdrive transmissions should run a 90 weight gear oil. The common GL-4 oil spec is getting harder to find these days. You can run the GL-5 oils if the refiner can state (right on the jug label) that it’s okay to use in transmissions with “yellow metals”…….ie brass, bronze, copper. Your T-86 has bronze synchro rings and usually brass countershaft thrust washers. We stock the Sta-Lube brand GL4 oils. At the moment they only offer it in the 140 wt (gallons only) but were supposed to bring back the 90wt gear oil. I need to check on that….
I had a Kei truck that needed GL4. I got Redline for it but also found that Nissan manual transmissions use GL4 80w90 for the same reason with yellow metals so, any Nissan dealer could get it locally if it’s not on the shelf. Most GL5 is marked compatible with GL4 but it’s not safe for yellow metals, and GL4 is extremely hard to find
Summit carries Driven GL4 80W90: https://www.summitracing.com/parts/...PQbKk9j95eVBGSKFJL9YNI-xVBr86rT03CSykqJBFMxfE
My buddy used gl-5 in his old style A833, and he noticed an issue shifting not too long after. Emptied it, and put in "yellow-metal" oil, and worked fine again.
I thank everyone for their thoughts. I went with Tractor Supply 90 wt Ford Tractor GL-1 mineral oil for transmission and 80/90 for the rear end
The Jalopy Journal
