Rear differential hub removal

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UTTAS
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Rear differential hub removal

Post by UTTAS »

Ran into an issue today removing a LR hub from my 37. This truck has sat for over 30 years when I got it running and had the brakes working last November. I had good pump-able fluid to all 4 wheels. It is possible the brakes didn't work when i had fluid at the bleeder. I never jacked it up to verify. I came back from Afghanistan a few weeks ago and i lost my rear brakes and no visible leaks.

I attempted to pull the hub and drum as an assy today and could not get it off. I loosened all the brake eccentrics and loosed the slave cylinder bolts to give me any leverage. My hangup appears to be on the bottom around the lower eccentrics. I pulled the outside bearing/axle shaft and hardware and can only get the hub to budge about 1/2in. It appears the shoes are clearing the drum.

I am very familiar with this style of brake system as we own 6 Willys jeeps and my 42 Willys MB. Does anyone have any ideas? I even mounted up the wheel on the hub and worked it for over an hour and still couldn't get the hub to come off. If you have any pointers please let me know
I'm pooped and this bigger stuff is a lot tougher than my Willys jeeps, :? :lol:
Thanks

UTTAS
Last edited by UTTAS on Wed Dec 27, 2017 8:16 pm, edited 1 time in total.
1942 Willys MB Slat Grill 114640
1952 Strick M-100 Trailer
1958 Dodge M37B1 L245-1196
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Re: Rear differential hub removal

Post by just me »

Remove the brake drum before removing the hub. Three screws and pull.
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Re: Rear differential hub removal

Post by Cal_Gary »

"Three screws and pull" will work unless those 3 screws haven't moved in 60 years.... If it's hanging at the bottom you might try taking those 15/16ths nuts all the way off to see if that adds some flexibility. Forgive me for asking but I assume you've pulled the axle shaft out first?
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Re: Rear differential hub removal

Post by rickf »

He mentioned the axle above, it is kind of hidden in there. If the shoes are clear it is sort of sounding like a seized bearing. They are not fun under any circumstance and only a lot of cussing and working of the parts will get them loose.

If the screws are there and stripped or unmoveable just drill the heads off of them and deal with the remainder of the screw later.
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Re: Rear differential hub removal

Post by just me »

I have been successful on a few trucks and other old vehicles using a hand impact driver to remove them. Only drilled one out. Pre oiling with Kroil and preheat with torch when stuck has almost always worked.
If you strip the head off, just weld a nut over it and put a wrench on it. The heat and greater purchase almost always works to get the drum screws out.
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Re: Rear differential hub removal

Post by W_A_Watson_II »

On the flat tip counter sunk screws, my best luck was with a small punch on the outer edge at the slot and a hammer, poor mans impact driver when the slot is shot.
Thanks,
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Re: Rear differential hub removal

Post by Elwood »

just me wrote:I have been successful on a few trucks and other old vehicles using a hand impact driver to remove them. Only drilled one out. Pre oiling with Kroil and preheat with torch when stuck has almost always worked.
If you strip the head off, just weld a nut over it and put a wrench on it. The heat and greater purchase almost always works to get the drum screws out.
This.

I've removed a number of drums, and have not yet had to drill the head off any of those flathead machine screws. Kroil followed by an impact driver for the slotted bit has gotten them all so far.

But if you do have to drill the head, welding a nut to the stub (once the drum is removed) is definitely the easiest way to go.
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Re: Rear differential hub removal

Post by UTTAS »

Thanks for the ideas I ended up using my air impact to get the screws out. This was after the hand impact didn't budge the screws. The brake drum came off without issue. The issue was indeed the hub, it was stuck on the spindle shaft. I had to use a pry bay to free it up on whatever the inner bearing was hung up on. My son cleaned everything in the parts washer and we didn't find any damage. The truck still has all the old leather seals for the hub. So we will be updating them while we are inside.

Thanks

UTTAS
1942 Willys MB Slat Grill 114640
1952 Strick M-100 Trailer
1958 Dodge M37B1 L245-1196
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Re: Rear differential hub removal

Post by Cal_Gary »

Indeed he did note pulling the axle shaft (I guess that's on me for posting during my Grave shift) :)
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