I'm a bonehead - 39 rear end questions
 

I'm modifying an '39 rear-end to spring-over for use in a 1930. In my genius I cut the original spring mounts off without noting which side is up on the tubes.

Does the weld run along the bottom of the tubes?

And a follow-up question, the bearing surface on one of the tubes is galled. Would it be better to sleeve or look for a replacement?

Thanks,
Carl

Re: I'm a bonehead - 39 rear end questions
 

I'm thinking once you cut the spring hangers off, it doesn't matter which side the axle housings are used on, and whether the welds go up or down. That becomes your call depending on your preference.
Now one consideration might be which way the zerk fittings face at the wheel bearing end of the axle housings, front vs. rear, but IMO, I would just put threaded plugs there, and plan on packing those hub bearings with fiber filled wheel bearing grease.

Re: I'm a bonehead - 39 rear end questions
 

Having no spring hangers would allow you to rotate the axle housing so the galled part of the bearing is to the top, where it would probably not wear any further.

Mart.

Re: I'm a bonehead - 39 rear end questions
 

On the galled bearing surface, it may be less costly to find another good axle housing than buying a sleeve bearing and paying to have the necessary machining done to install a sleeve bearing.

Re: I'm a bonehead - 39 rear end questions
 

This is interesting, that galling is only in one spot and not that bad, will post photos over the weekend when I get back to the shop.

Do others agree with this line of thinking? Also worth noting, I'll be using new roller bearings, not the ones that caused the galling.

Re: I'm a bonehead - 39 rear end questions
 

These photos show a 40 rear which is almost the same as the 39. Weld is on top.

Re: I'm a bonehead - 39 rear end questions
 

I agree with JM 35 Sedan. it's taken 80 years to gall the bottom of the bearing surface. The top of that surface never sees hard use, so save your money and time, just flip them bottoms up unless you want the clean look of weld on top. The zerk was eliminated on later housings, so that's not an issue either.

Re: I'm a bonehead - 39 rear end questions
 

It was a common practice to turn 35-6 housings over to get better bearing surfaces.
There is a drain hole in the bearing web for oil to get back to the center section. You should drill some new ones on the opposite side.

Re: I'm a bonehead - 39 rear end questions
 

very helpful info all. Thank you!

~ Carl

Re: I'm a bonehead - 39 rear end questions
 

Andy's post above:

I didn't know that about the oil drain holes. There must be loads of flipped axles out there with the oil holes in the wrong place.

Mart.

Re: I'm a bonehead - 39 rear end questions
 

Me too. But then, the center section would need to drain first, and how often is that going to happen?

Re: I'm a bonehead - 39 rear end questions
 

Quite often with a rake and a bad torque tube seal. The trans can get really full.

Re: I'm a bonehead - 39 rear end questions
 

Since we're doing Banjo questions,,, Is there supposed to be a seal inside the axle tube near the narrow end? If so , I presume the tube must be removed to install it. Does it just hammer in? How does the old one come out if there's one in there?

Re: I'm a bonehead - 39 rear end questions
 

Yes, it is installed from the diff. side. You knock them in toward the center. I welded a washer to a piece of conduit to install them. The washer needs to be square to the tube. I put tape on the conduit to build up the diiameter to hold the seal.

Re: I'm a bonehead - 39 rear end questions
 

More good advice!

Any other useful tidbits while this thing is apart on the bench? I have all new seals, gaskets and bearing from Mac VanPelt. Any more advice on assembly would be appreciated.

~ Carl

Re: I'm a bonehead - 39 rear end questions
 

Here is a good tutorial. It is for model A but most apply's to V8.


http://www.santaanitaas.org/wp-conte...vised-2014.pdf

John

Re: I'm a bonehead - 39 rear end questions
 

We use to flip the galled and pitted countershafts upside down all the time in the fleet of 1978 Ford 3-speed van transmissions at work. Saved us $12.00. They'd go from being really noisy to nice and quiet. There is no down force on the top side of the shaft, only on the bottom.

The hot rodders use to flip the early Ford axle housings upside down and then swap housings from side to side. That puts the spring hangers lower on the housing and drops the car in the back. Bernie Couch has owned his '32 roadster since before WarII, I think he bought it in 1937 and first used it to deliver newspapers. He is the one that taught me to swap to axle housings to lower a '32 Ford. You do need to cutoff the radius rod brackets and weld them on the bottom. That would probably warp the housings. Nobody worried about that stuff back then. He raced it El Mirage from around 1948 to 1950. Drove it from CA up to Washington. He drove it all over the place and he never had a problem with the rearend setup that way.

Re: I'm a bonehead - 39 rear end questions
 

Wrap the axle ends with electrical tape to cover the keyway. The tape prevents the sharp edges of the keyway from cutting the seal inside the axle housing as it passes through .

Re: I'm a bonehead - 39 rear end questions
 

Don't chase the mounting bolt holes on the banjo. They are intentionally tight to prevent leakage. You will still need thread sealant, though.

Re: I'm a bonehead - 39 rear end questions
 

This is turning into a very informative thread - thank you all.

Carrier bearing - any tips about removing them from the differential? My pulley puller isn't up for the job, and I can't hold it correctly to use my press.

Thanks,
Carl