Bob's Resource Website (2007)

Studebaker T-85 Transmission rear seal
NOTE: The Trucks ARE the same as '56-'57 GH & Pres. Classic Short Tail O.D. that use: 1540818. These are No Longer Available!
But '58 GH T-85 Long Tail, is 1545164
And '61-'64 T-10 4 Speed is 1555257

This is a Borg Warner model T-85C-1A for a 1956 Studebaker Golden Hawk 56J. This transmission has the much stronger Borg Warner R-11 overdrive that has four gears in the planatary instead of three.
The T-85 was used on 56 thru 58 Golden Hawks, Hawks,Commander and Presidents that had ordered the heavy duty transmission. It was Standard on the Golden Hawks, Police cars and Taxis.

This transmission can be used with the 289 Studebaker V8 by changing the input shaft to pn 1540811 and the front Bearing retainer to pn. 1540810. Everything else is the same. You must use Belhousing 1539373 from 56 to 58 or 63 to 64 V8 cars. This transmission was much stronger that the T-86 found in most 3 speed Manual cars. The shipping Weight with crate is about 140 pounds.

The history of the T-10 transmission (GM ST-10) begins with the Borg Warner T-85 3-speed which was the basis for the Borg Warner T-10 4-speed first used by GM in 1957. It had a 9 bolt side cover and was commonly refered to as a "Sideloader".

First: 2.97:1 or 2.49:1; Second: 1.59:1; Third: 1:1; plus Overdrive
Reverse 3.15:1

t851a.jpg t851b.jpg t85i.jpg
t85f.jpg t85g.jpg
ford3speedt85forweb.jpg overdriveforweb.jpg
R10/11 Overdrive Manual

T-85 Rear oil seal

1.561" id, 2.837" od, .592" wide.

Seals with similar specs (leyrret/SDC Forum)
SKF 15234 shaft size-1.5, bore size 2.835, O.D. 2.839, width .313
SKF 15324 shaft-size 1.535, Bore size 2.835, O.D. 2.844, Width .315

(I checked shaft and bore size on t-85. Bore is about 2.840-42, shaft 1.560-63.
The second (seal) number should be a good fit. The .028 difference in shaft diameter
shouldn,t make any difference.

It is the same seal used in truck (Stude?)T85s up thru 1964. Studebaker part# is 1540818.

The Stude # cross references to Chicago Rawhide R11 110, also cross references to Garlock 63X8078, but appear are NLA.

Ingvar Vik, from an old TW issue, showed where he developed a retro fix for this seal

Curtis French in Tallahassee, FL (Black56Hawk/SDC Forum)
had to replace his seal recently and couln't find the specified replacement.
The Vik fix came in handy

Okay, I basically used Ingvar Vik's idea of using an available seal and a machined adapter ring (I have a friend with a machine shop), but was unable to find the National 10864S seal that he used. Instead, I used a National 8160S. Here's the machined adaptor ring , which uses the same dimensions as Ingvar's, and the National 8160S seal.

Here's the adaptor ring in the transmission (obviously the old seal had been leaking for a while):

The seal in the adaptor fit perfectly, and the universal-joint flange fit the seal. It's all together now and works great!