3500 front hub info needed

[abus319]

I'm in the condition assessment phase of the 3500 and pulled the front wheel hubs to have a look at the brakes and bearings. I ran into a couple things I didn't expect.
There was no grease in the hub only what looks and smells like gear lube. I am only guessing here but viscosity is something around the 250 range. Is this grease that broke down or actual gl? The service manual says it should be S-2, high temp grease.
The second question is the seal on the rear bearing. It has some kind of apparatus with tabs, in the hub that seals against a rope type seal mounted on the axle. There is no mention of this in the manual or how to remove it to inspect the bearing. I didn't want to try to drive it out until I knew a little more about how it works.

[quest]

I'm in the condition assessment phase of the 3500 and pulled the front wheel hubs to have a look at the brakes and bearings. I ran into a couple things I didn't expect.
There was no grease in the hub only what looks and smells like gear lube. I am only guessing here but viscosity is something around the 250 range. Is this grease that broke down or actual gl? The service manual says it should be S-2, high temp grease.
The second question is the seal on the rear bearing. It has some kind of apparatus with tabs, in the hub that seals against a rope type seal mounted on the axle. There is no mention of this in the manual or how to remove it to inspect the bearing. I didn't want to try to drive it out until I knew a little more about how it works.


By rear bearing I assume you mean inner bearing of the front hub.
I have seen this seal before and it's just the way the casing is manufactured. It was made in two pieces. You are safe to tap it out however I would personally get new seals for two reasons; when I worked in the brake repair shop we never reused an old seal, after it was disturbed it was replaced because the chances were the vehicle would end up coming back with a leaking seal and possibly ruined the new brake linings which we would have to eat the cost on fixing it all; second there is no way of knowing ahead of time how much damage you would do to the seal or its casing when attempting to remove it, it might come out nicely or it could be tough, damage pretty much means the end of it.
Seals are cheap so get your hands on a couple of new ones to be on the safe side. If it was only a farm or acreage truck it wouldn't be a big deal.
As for the lube I would say you are correct about old grease breaking down, if the bearings are nice just repack them and throw some extra grease inside the hub.

I'm doing brakes and all that fun stuff on my old girl right now too, beatup 65 GMC 4x4!!!

Good luck
Thomas

[quest]

oh and I just had a closer look at your picture. That appears to be and old leather seal that is almost completely gone, worn out, you can see all the wetness on the outside of the hub spreading onto the inside of the brake drum. this tells me that you should do all brakes and seals and possibly wheel bearings. worn out and out of adjustment wheel bearings will wreck your seals as well. Because it's a safety issue I would definitely check them all, to get proper safe braking you have to do your wheels in pairs, front together and back together but all four is the best thing to do. With that much seal leakage your brakes linings are going to be damaged soon or already are, I would also guess that your wheel cylinders will be sweating or leaking by now as well.

[abus319]

Thomas
Thanks for all the info.
Yes, I was referring to the inner bearing seal. At first it looked like the seal was threaded into the hub and since parts can be a bit hard to find I figured I would ask before I started making assumptions. I think I will try and find new seals before I tap them out though.
The outer bearing are pitted and really need to be replaced so I assume the inner(s) will be the same.
The wheel cylinders and the linings appeared to be in good shape and dry on that side. That really doesn't mean anything though. The brakes on this truck haven't worked since I purchased it in 04. The Hydrovac is seized and there is no fluid moving past it.
At least I can make an attempt to find parts etc and guestimate the cost of the brakes.

[quest]

Do you mean hydro-boost or vacuum power booster, what year is this truck? Do your wheel cylinders look good when role back the rubber and peek inside, should be nice and clean with no corrosion and the rubber should not be dry or cracked and should easily be able to slide the pistons back and forth in the cylinders?

If your rear diff bearings are toast as well keep in mind that you will need to completely drain all the gear oil from the diff and put in a fresh load in with the new bearings. I like to preload the rear bearings with a little bearing grease when I reassemble it to be sure they are not starved of lubrication when they turn under load for the first time. After that the gear oil will do the job.

I have a 65 3/4 ton 4x4 with manual brakes, a full line of replacement parts was going to run me about $750 a couple of years ago, including drums and brake cables.

[abus319]

yes, I was referring to the vacuum power booster. The truck is a 1960, 3500.
The cylinders look ok, not great, rubber is good. I will try moving the pistons tomorrow. I found the outer bearing and cups and possibly the seals. I need to remove the seals and inner bearings to get some accurate measurements before I call vendors.
The Drums have been turned at least once so I need to verify that they haven't been turned more that the .060 limit. I don't have any calipers that large,yet...

[quest]

yes, I was referring to the vacuum power booster. The truck is a 1960, 3500.
The cylinders look ok, not great, rubber is good. I will try moving the pistons tomorrow. I found the outer bearing and cups and possibly the seals. I need to remove the seals and inner bearings to get some accurate measurements before I call vendors.
The Drums have been turned at least once so I need to verify that they haven't been turned more that the .060 limit. I don't have any calipers that large,yet...

Your seals and bearings may still have visible part numbers on them for reference. There does seem to be resources for brake drums so you should be able to find those but if your drums are slightly oversize I would still use them if this was just going to be an occasional cruise vehicle as long as they are not way oversize, on the other hand if you are going to put it to work then get the new ones in that case.

[abus319]

It will be a work truck, it needs FULLY functional brakes.

I'm not quite ready to start on them yet, I still need to roll it out one more time for a power wash and a block/rust flush. Once I get the engine all squared away I will move on to the brakes. I just wanted to get an idea if the components were available and were priced within reason.

You were right on the leather seals. Once I get everything cleaned and flushed I will tap them out to see it there numbers on the inside of them, there were none on the outside.

So hows your brake project going?