The Stovebolt Site Forums The Shop Area Driveline Hub removal help

Afternoon,
I'm slowing making progress on my 1951GMC 450. I've finally gotten the drums off, now I'm hung up on what axle nut wrenches I need to remove the hubs? Can anyone shed some light on these, please. Also any tips on the oil seals as well would be appriciated.

Thanks In advance

Are the nuts hex shaped, if so suitable wrenches are available, some are available that fit 4wd vehicle hubs(source). Seals usually have number on them.

Ed

If the hub nuts are round with slots in them for a spanner wrench, I've fabricated my own wrenches with a piece of pipe with short pieces of key stock welded to it. Some of the nuts have four slots, and others have six. Either drill a hole in the pipe for a long tapered punch as a lever, or just use a pipe wrench. There will be a locking washer between the two nuts, with tabs to bend down into one of the slots.
Jerry

Sorry all, I spaced adding the pic.

Saw Mill, Measure the hex nut face to face dimension and then search for axle bearing hex nut sockets (like below) with the size you need. Lots of vendors selling just a single sized socket for what you need, with some even available from your local Flaps. If you post the measurement I would be glad to see what I can find for you.

Gdads51,

Thanks for the reference. It's appreciated. I'll get those measurements when I get home from work.

Thanks again

I've replaced dozens of hub bearings and seals with nothing but a drift punch and a ball peen hammer. It makes the nut look pretty gross after a few times, but on a road service call out on the side of the highway in the middle of the night, one must use the tools he has on hand. Like John M. is fond of saying- - - -"If you don't have a dog, you hunt with the cat!"
Jerry

I can't tell from the picture but most of these have two nuts with a tabbed washer of some sort in between. Perhaps that's already been removed. Any how when putting a two-nut assembly back together be careful not to tighten the inner nut too tight because when you cinch down the loc nut it will take up the slack in the threads of the inner nut and the bearing preload will be too great. There should be instructions in the Timken or Eaton book Or maybe your GMC book describing the procedure to set proper preload. Too loose is just as bad as too tight. Just right is golden. :-)

You can get the numbers for the bearings right off the bearings, same with the seals unless the number is inked on the outer circumference. Measure the hub diameter at the sealing surface and the bore into which the seal fits and go to a bearing and seal catalogue to get current numbers if you can't cross reference. The Timken catalogue will have what you need but you may have to buy from one of the bearing houses as Timken doesn't sell direct so far as I know. Avoiding NAPA will save you a lot of money on seals and bearings.

1Ton_tommy, thanks for the advise.

OK all, I've gotten then nuts, washers and the first bearing out, but I can't get to the rear bearing. I can't seem to figure out how the hub actually come off to access the rear bearing and oil seal. Can anyone point me in the right direction? Thanks

Pull harder. Umpteen years of grease hardening up in there will make things tight.

There is a possibility that the inner race of the inner bearing has welded itself to the spindle, which means that you have to pull with enough force to separate the seal from the hub, leaving the seal and bearing on the spindle. Then you might need a bearing puller to get the rest off.

That hub assembly should slide straight off the load tube. Sometimes it requires a little "persuasion". I like to bolt a piece of heavy chain to one or two of the threaded holes where the axle shaft attaches, and use a "whiplash" motion to yank the hub off the tube. Once the hub is off, it's a fairly simple job to pry the seal out and remove the inner bearing. I seem to remember one of the medium duty Chevy/GMC truck rear hubs that has a bearing race retained in the hub by a big snap ring. It takes a special pair of snap ring pliers and a few colorful vocabulary words to get that ring out!
Jerry

I'd have to agree with Jerry if there's a snap ring holding the inner bearing race in place, it would take more than a few colorful vocabulary words to get at that snap ring with the hub still in place. Why GM might have decided that snap ring was necessary is beyond me other than keeping the wheel in place if the nut happened to come loose on the outer bearing and prevent the wheel, hub and axle from coming out of the axle housing while going down the road. Pretty unlikely occurrence. Even so, the pull harder comment would apply, but it would take more than Jerry's chain "whiplash" to pull the hub off the seal. A jack behind that chain bolted to a couple of lugs and bearing on the axle tube would do the trick.

Saw Mill, I don't have access to a 1951 GMC Shop Manual covering your 451, but there is a 1955-59 GMC Truck Shop Manual free to go through HERE.

Diving into that book, there is a cut-away diagram of the 1955-59 450 Series rear axle hub and bearings on Page 661 which I snagged and included below in case the hub and bearing design is the same/similar and could help you picture what you can't see through the hub and brake drum. Looking at that pic, I don't see anything other than the inner bearing and seal riding on the axle load tube, so maybe all it will take is more persuasion as Jerry mentioned above. Let us know how it works out.

Perhaps there is one of our GMC Gurus that has the correct resource book with more details about the 1951 450 Series rear hub and bearing???

The snap ring holds one of the OUTER races into the hub- - - - -the hub still slips off the spindle easily. It's just a real female dog to get access to the ring so the bearing cup can be replaced once the hub is removed.
Jerry

My '39-'54 paper GMC Master Parts Book goes from 100 to 470 models. I'll look tomorrow and see what i can find. It won't have overhaul instructions, but maybe a parts drawing will help.

I don't know if this picture of a 450 hub from the GMC Master Parts Book will help any, but here is is. Sorry about using my phone instead of a scanner, but the book still has its original binding and pressing it down flay would probably break it. Ignore the stuff in the upper right of the picture. It is from a different model's hub.

One thing for sure, no snap ring is shown. Looks like there are 2 different outer locking schemes, probably depending on year. 19.0620 & 19.0630

Thank to all for the pointers.

Bill Hanlon, do you have a pic of the cover for the parts book you're referencing? I'd like to find one. I've looked on ebay and am not sure if what I've found is the same

Your eBay book isn't the same as mine (shown below), but should contain the same data as far as your '51 451.

Bill, thanks for the pic. I appriciate it. By the way, found one like yours on eBay. Thanks again

If the condition of the two books on eBay were the same and price wasn't a factor, I'd recommend the one like mine. It covers many more years and does cover the smallest through 470 series in 960 pages.

I actually picked up the same as yours. Should be here Saturday.

Thanks again

Better reading than a Clancy novel!

This is the box for the hub seals on my 52 Canadian model 1783. 3 Ton gmc chassis.
Not sure if it's helpful but hopefully.