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Hello out there! Just recently purchased a 1929 AA that is an early restoration (1986), but was in storage for several years. I am going through and changing all the fluids, and have flushed and added new 600w to the rear-end.

Question: There is a separate and smaller fill plug above over the worm drive, what is required here for proper lubrication??

Thanks!

Pat

On top in the rear of the worm drive is suppose to be a grease fitting for the thrust bearing. Maybe someone has just put a
plug in place of the grease fitting. You can take the four bolts out and remove the thrust bearing nut and remove the thrust
bearing and repack it with grease.
Tim

Actually they came from the factory with the pipe plug, not a grease fitting.

Keith

Thanks gentlemen, either way the bearing requires grease not 600w??

No, I don't believe the thrust bearing was to be greased. Ford did have problems with the thrust bearing and bearing covers, but both were redesigned and changed. Also the bearing cover and the face of the housing called for a surface with no greater than a .010" variance in its flatness. People might have added a grease fitting as their cure for the problem if the rear bearing cover leaked, but as far as I know they were designed to be lubed by the gear oil. See my response to "oldtimerhobby" as to his question "1928 AA-rear end" as the type of oil to use in the worm drive rears.

Keith

Thanks Keith!

I think the worm drive differential must have been a carry over from the T era, a friend has a 1925 TT with a very similar arrangement.

Pat

I got my information from the AA Truck book by Jim Schmid on page 20. Attached is a drawing of what the rear end
looks like internally. If the rear end oil is to get to the thrust bearing it will have to lift the oil up and over to the bearing.
I can see why there was problems with this method. Make up your own mind. I will trust the grease.

I have a 32bb and don't have that. But according to that schematic I would remove that grease fitting, take it for a ride around the block and see if any gear oil leaked out the hole. That should answer the question.

Here is a quote from the Model T Ford Service Bulletins on lubricating the truck differential.

"The worm, worm gear, differential gears and pinions, worm roller bearings and thrust bearings, are enclosed within the
differential housing and lubricated by the rotating worm gear, which throws the oil held in the bottom of the case to all of the
above parts."

i know the thrust gets hit with oil because it leaks out off the cover. i will have to make a cork gasket. has anyone run the 600w oil from snyders in bronze gears with no problem. i am using lupriplate but think it might be overkill and 2x the money.

birdacre wrote: ↑

July 31st, 2021, 2:28 pm

i know the thrust gets hit with oil because it leaks out off the cover. i will have to make a cork gasket. has anyone run the 600w oil from snyders in bronze gears with no problem. i am using lupriplate but think it might be overkill and 2x the money.

I have been running the 600 W for five yrs. + with no issues... Just make sure it has plenty in it!!

this is what doug from snyders said. he said they use it in model Ts that have bronze gears. thank you for info. like to be cautious but also hate to waste money.

Kim VO said she has used the vendor 600w for 5 years with not issues to the bronze. i will contact doug and tell him our experiences. sounds like a good safe economical safe solution. thank you kim.

birdacre wrote: ↑

August 1st, 2021, 9:12 am

Kim VO said she has used the vendor 600w for 5 years with not issues to the bronze. i will contact doug and tell him our experiences. sounds like a good safe economical safe solution. thank you kim.

SHE !!!!!

i don't get the SHE comment?