Hi guys, now the the y block is up and running, it's time to turn my attention to the gearbox and overdrive. I'm no expert but I think I have an R10 Borg Warner overdrive attached to a 3 speed manual box.




Question is- when I pulled the engine and box from the truck, I noticed oil had been flung around under the cab where the drive shaft connected. Is there a seal (see photo) to stop oil from leaking out of the overdrive? As soon as I tilt the overdrive, oil pours out.



Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.

Dennis,
Yes... you are looking at the rear seal in your last pic. Your drive shaft yoke when installed onto rear splines makes the seal. Totally normal for gear oil to run out when trans is tilted with yoke removed. Seal is easy replacement. Make sure your yoke is in good condition , no groves, rust , etc... A worn yoke can also be a sign that the tail bushing is worn also which will take out a new seal quickly. Make sure you fill the trans main case & overdrive case to the bottom of both fill plugs before driving. You have the Ford built 3 speed with the Borg Warner RG 10 , 3 pinion planetary.
Mike

Thanks Mike, that's the info I was after. I suspected there was a seal there somewhere. I took to the seal and pry'ed it out. Now I just have to find another one- seems hard to find online. Any ideas?


Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.

I put that same OD trans in my 1960 F100 and if I recall it used the same seal as the standard 3 speed. Clean the seal off so you can see the number, I can just barely see it in the picture

http://www.macsautoparts.com/ford_truck_late/ford-pickup-truck-transmission-overdrive-housing-seal-all-with-overdrive-f100.html

Rear tail seal with 1 1/2" yoke....
Federal / Mogul 410059
Any good parts or bearing house should be able to cross reference ...
Correct same seal was used from 50's - 70's & more Ford built 3 & 4 spd's with 1 1/2 " yokes 16 or 28 splines....
Mike