30/31 AA Torque Tube Driveshaft Seal

[E.Moore]

Does anyone have any recent experience on replacing the driveshaft seal behind the Torque Tube driveshaft upper bearing race? I've discovered that there are three different KRW race removers. There is the A, then the one with raised letters AA/BB and another one that is sized in between the two with no markings. The one in the middle is perfect for removing the bearing race. The KRW tool marked AA/BB is way too large & will not get own into the race.

Once the race is removed, getting the seal out was not too bad, but finding a replacement seal has been a bear. Sacramento Vintage Ford Parts has been on backorder for these for several months.

Does anyone know of a vendor who stocks that seal (AA-4686 - For 1930-1931)

I've found that (2) Timken seals, (471766) installed with the first one facing the pinion gear and the second one facing the transmission will work. Both of them stacked together are the same height as the original seal and the bearing race snaps back into it's indention. The seals should not be installed the same direction because the bearing will ride down off of the bearing race and into the upside down seal case, causing a quick seal and bearing failure.

I'd like to install the same type of seal that was originally used, so the call goes out to see what are you guys using when you get to this for repair?

The seal size identifications numbers on the box are not correct. The parts source said that Timken had a known issue with the size ID numbers on their boxes. The seal is 2" OD for a shaft of 1.250 and is 1/4" tall.

[Bob C]

I looked in the seal interchange and AA-4686 crosses to NAPA 47370 OD 1.987 ID 1.250 W .437. The 471766 should be OD 2.004 ID 1.250 W .250.

[E.Moore]

Bob, Thanks for the information. I tried to get the folks at NAPA to cross it over, but if the old number is not in the computer these days, it's no longer available. The old number was not even in their current edition parts books, which another NAPA looked at. If the crossover number is available, I'll post a reply.

[Bob C]

The KRW tool is probably for the BB only as the drive shaft is bigger. The BB seal is 2.110 OD as compared to the 1.987 of the AA.

[E.Moore]

I went to NAPA today and looked at the NAPA seal, part number 47370 (Victor), It also crosses to NAPA numbers 12407 & 12437.

Those seals are not as good as the Timken 471766, in that they do not have a spring tensioner on the back of the rubber portion of the seal.

The NAPA seals are all 1/4" width. The original AA-4686 is approiximately 3/8" width.

Two of the new seals have to be used to make up the difference in thickness of the original seal, but one seal has to face the pinion and the other has to face the transmission, otherwise the driveshaft bearing will not stay in place in it's race.