Well the trucks only a week or two away and I need to find out a little about the diff before I will drive it away from the yard to home about 30mins away but its a hwy run.
The diff was leaking quite bad when I saw it so what sort of gear oil do I need? I cant remember seeing a filling or draining point? What is the likely cause of leaks in this type of diff? I did pick up a gasket kit along with heaps of other gear from CW Moss when I was in the US, seemed to be different thickness' for gaskets. Is there a thread on replacing gaskets?

Cheers.

 

Talkwrench
I take it that you're working on a typical prewar to '47 rear end. In that case the gaskets are a different thickness to facilitate setting the differential carrier bearing preload. After that you will need to move the gaskets from one side to the other to set up the backlash. The main cause of oil leakage in Ford rearends is worn bearings. Check the roller bearings in each wheel hub. Be very careful choosing replacements as there are some aftermarket bearings that are pure garbage. Get replacements from reputable vendors. Oil? 90w, 80/90W, 75/90, 75/140, I've seen them all. I use 75/90 from Shell and no problems. Some rave about Amsoil synthetic. Most are good. Hope this helps.
GMS

 

THanks, I have been looking into these "Banjo" diffs a bit more.. Not sure if I should be frightend yet..
Looks like they will take just about any gear oil.. I read somewhere that from the factory they had 600 wt oil..gezz that will slow down the leaks..!
Im sure I have 80 -90 and also some 85 -140 . Seems that you should look for a GL4 type?

Anyway I have my fingers crossed that it may just be leaking from the bolts, so if I can pull them out one by one and seal the threads I might get lucky. The leak was quite bad though everytime I drove it out of my friends garage and back in there would be a puddle under it and it really went nowhere..

 

Yeah, it could be just the bolts that are causing the problem. I'd drain and flush the rearend completely then remove the bolts one at a time using Loctite liquid thread sealer or liquid teflon. Those old gaskets can go brittle over the years so if the leak persists there, you might have to go for a major. The lube I use is GL5. I keep forgetting to use the SAE rating as I've taken it for granted over the years.
Good luck with your project,
GMS

 

Hi just wanted to let you know that their is a 1939 ford truck rear end, a rolling chassis and even a customized 39 Ford truck truck in need of full restoration. They are at an auction in Alabama. It is also on line. You can take a look here. Pearce & Associates
Good luck
Mark

 

Hi Wildman
I just took a look at the '39 truck. It looks like someone grafted a '40 deluxe car front clip on it and I have my doubts if the bed is even a Ford because the fenders sure aren't. Might be some parts one could use but how do unchop a top? Thanks for the link just the same.
GMS

 

Hi, Your right about the front end. This truck was customized in the mid fifties. My dad worked at the shop at that time. He purchased this a few years after it was customized. The truck was chopped, sectioned, channeled and lowered. I can't say about the fenders. I think they were also modified.

There is a rear end in the auction that is a 1939 ford and some other parts for a 1939. I hope there is something you a re looking for. If not thanks for taking a look.

 

I looked at that complete chassis and keep wondering if I should as I've got a '38 pickup in the works and could definitely use some chassis pieces. Trouble is, I'm on the Montana/Alberta border and shipping is going to get out of hand. It's even a hike for my brother to head out from Las Cruces NM to get it. I'll keep an eye on it. Thanks a bunch for the heads up.
GMS