Noisy rear axle...

"...did you exceed the
50 mile warranty on the seal?"

LOL, probably...

No, I noticed two years ago when I pulled off that axle that it was difficult to get the C-clip out. So it's always been a bit tight. I had to tap the flange end with a dead blow hammer to get the c-clip back on after installing the Timken repair bearings. Most likely that is what damaged the seal, it just took me a while to discover it. I was expecting diff oil to be dripping from the brake assembly/drum, but that never happened. Just enough to ruin the brake pads, though.

The MasterPro double seal bearing has the second seal riding over 1/2" inboard of the repair bearing rollers. So I think it will clear the original bearing path and ride on a smooth sealing surface. Time will tell, I suppose, once I install the darn thing.

I'll try not to overdo the turning (not grinding) of the excess flange material. I promise. You have to allow a machinist to have his fun.

I called a local gear man (who apparently specialized in rear axles), and asked him if he could get replacement axles for this van. I'll need to pull the existing ones (still haven't done it) and take measurements of length, splines, etc.

I mentioned the repair bearings and his brief assessment was: "A waste of time and money. They leak. The rollers are smaller than stock in order to fit into the beefed up outer casing, and they chew up the axle faster. They are all right for getting you back on the road in a pinch, though". Or words to that effect.

So... I'm gonna install the new double seal repair bearings this weekend (work permitting) along with some minor grinding. Take careful measurements while the axles are out, replace the rear brake shoes, etc. Then I'll see if he can get some replacement axles.

PS-The van has more get up and go since I corrected the over-adjusted parking brake... go figure...

It's been two years... I don't remember there being any problem getting them out.. I have a variety of pullers so either had one that worked well, or the bearings weren't in there real tight to begin with.

The puller you pictured doesn't look familiar, though, not with that cross bar. But it doesn't mean I don't have one. I guess I should sort through my bearing puller collection before starting the process.

PS-the inner seal on the double seal bearing is thicker and more substantial than the outer seal. It actually has two lips.

Well, if I can find new axles for a reasonable price, I'll share that info.

I probably also will show the axle man the "new" double seal bearings, to see what he thinks - although I might have already installed them by the time I get around to getting new axles from him.

Yes, it's possible that the pre-greased bearings might leak grease, but I think it's less likely than if they were containing diff oil. As for diff oil vs grease - I think it's a wash in terms of bearing life. After all, many wheel bearings get by on grease alone - such as front wheel bearings, including those at the ends of front wheel drive CV joints. And grease is just basically a semi-solid carrier for lubricating oil. Of more concern is probably the small diameter of the more numerous rollers in the repair bearings. I counted 14 of them, vs. the 13 you mentioned the stock bearings have.

However, I'm counting 15 rollers in the Timken bearings. This may mean the double seal Master Pro repair bearings will last a bit longer than the Timken repair bearings.

I agree, I'd MUCH rather have a real axle bearing with an inner as well as an outer race - but as far as I know that would require an entirely new rear axle assembly. It needn't be a sealed bearing, just with an outer seal that works.

I'm sure the axle guy would dismiss the double seal bearing as crap as well. But I think it's better smelling crap than the Timken approach ;-).

Basically these axles are made to a price point. It's cheaper just to use the axle as the inner race, but not as good as a real bearing. The axles are hardened, so it's not a hard roller on plain steel, but probably not as hard as a real bearing's inner race would be. We're looking at disposable technology here, which would be ok if replacement axles were readily available for a reasonable price.

Tomorrow morning I gotta go to work. I'm going to try to pull the axles this afternoon/evening, and bring them in to turn on the lathe at work after I'm done with the company stuff. I can always hand grind them if that doesn't pan out.

Well, I pulled the axle shafts and bearings tonight...

Had a great set of rear axle pullers. Just couldn't for the life of me find the slide hammer I used last time. Finally found it in a unlabeled but nice black steel original case under the workbench.

Now, the left (driver's side) hand bearing was leaking the most. This is also the side where the axle was more difficult to remove the C-clip two years ago, and more difficult to install the repair bearing, and more difficult to pull the c-clip again today as well.

I can see some scarring on the rubber of the left hand seal. Whether it's the cause of the leak I don't know yet. But it's probably from tapping the axle in on install of the repair bearings two years ago. The right hand side wasn't difficult to pull the c-clip on, and the seal there wasn't leaking much. No where near as bad as the left hand.

After I cleaned up the axles I brought them inside for careful measurement. Turns out they are slightly different lengths. I gather the proper way to measure an axle shaft is from the tip of the button to the wheel side of the lug flange. The left hand side measures 31.25". The right hand side measures 31.3125. Or 1/16" longer. Not much, but enough to explain the difficulty in installing the and removing the left hand side axle vs. the right hand side. I figure they both should be 31.3125, but GM figured the 31.25 out of the parts bin would work just as well. I *may* try swapping them around (no telling if somebody before me got them mixed up) and see if they fit into the c-clips better that way.

I'll also inspect the wear pattern on the brake drums to see if the different lengths show up there.

I did some internet searching for 28 spline 31.3125 replacement axles, but didn't have much luck. This differential is supposed to be an 8.5 ring gear unit. I did find a 28 spline 31.3125 axle, but for a 7.6 something GM diff. Don't now if that would fit or not.

Needless to say all the sites I've visited so far don't list any axles specifically for the '67 Chevy van. Not too surprised there.

Tomorrow I'll see if I can relieve the flange end of the axles to give the repair bearing outer seal more clearance, either at work on the lathe or at home with a hand grinder. I would prefer the lathe at work but there may be some issues getting the axle to run true in the lathe. It's a forged shaft, and only the bearing surfaces and the lug flange are really true to center. So holding it in a chuck by the non-bearing surface shaft probably won't work too well. I'll have to see if I can set it up to run between two centers (each end of the shaft has a depression for a center to ride in).

While I'm at it, I'll probably give the diff cover a good sand blasting, and then powder coat the outside of it a nice bright yellow... just like the front brake backing plates...

I also installed one of the MasterPro dual seal repair bearings on a clean axle shaft. The inner seal rides completely on the unworn inner polished bearing surface, no worries there. But the outer seal looks like it runs VERY close to the flange, so if i can get a good setup on the lathe I will try to smooth that area out a bit so the outer seal has a better sealing surface - esp on the left hand shorter shaft.

OK, gotta hit the sack to earn more $$$ to pay for all this junk.

On mine the stock shims on the carrier differed by .015 from side to side. Where I ended up I can't remember now. but the drivers side seemed to take a bit more pressure to get the clip in when I put it back together, that small difference may have been a factor, The clips are an easy 1/8" thick and thats about what the seal on the repair has to be able to stretch or slide over without tearing, once in, it set back on the smooth surface with a very little bit to spare. A lathe long enough to chuck up the axle would be great, but ours wasn't ,, so a grinder was the tool.

"A lathe long enough to chuck up the axle would be great..."

Well, come to think of it...


Here's what I did today. I snapped this photo in the middle of the turning process. It came out reasonably well. I could tell that the metal of the shaft is hardened because even at a relatively low surface speed with a carbide insert cutter, the chips were blue from the heat.

And here is the wide angle look at the full set-up. It's a big lathe. I put the axle between two centers, and used an extension on one of the lug studs to hook onto the chuck to spin the work. This is the left hand axle. The right hand axle, the longer one, wasn't as well centered, but I was able to relieve the flange area on that as well.

Another try at the wide view...

And this is a look at both relieved axles...

Side by side. First, the original driver's side axle...



Then, after it was relieved on the lathe:

"You're the one
going to be relieved..."

*Groan*, LOL.

Didn't get much more done today. Afternoon siesta to catch up on lost sleep. Cleaned up the diff cover in the parts washer, and bead blasted it preparatory to giving it a nice yellow powder coat. Also cleaned up the brake drums. Still have to disassemble the brake hardware and clean up the backing plates, but that shouldn't take too long.

After pulling the Timken repair bearings, I noticed that they had scraped a fair amount of metal from the bore in the bearing housing at the end of the axle. This showed up as hair-like metal filiments. Initially I thought they were some sort of animal bristles. I ran a magnet into the axle tube on both sides, but it didn't pick up any more shavings. Which is good. I think these shavings may have been shoved forward of the bearings, and caused the Timken repair bearings not to seat as completely in the housing as they otherwise may have. I may stick the new repair bearings in the freezer overnight so that they are easier to install tomorrow.

Independency day update #1:

Got back to work on the axle bearings. Took apart the brake assembly on each wheel, one by one. Then installed the repair bearing. No big problem, but when it came time to install the new brakes shoes, discovered that what Autozone sold me 2 years ago (I got a rear set when I re-did the front brakes but never installed them) were the wrong shoes. Got new shoes at local Kragen (they had them in stock) and went on to the second wheel. This bearing didn't go in as easily, and was sticking out too far. It looked like it got slightly cocked, so I tapped it gently (well, hard) on the edge that was out too far, taking care not to damage the outer seal, which I didn't. Then back to the bearing installer and finally got it seated square. I wanted to avoid having to pull the bearings because that likely would ruin the inner seal and require replacing it.

These bearings protrude about 5/32" (about .150 to .155 on my caliper). I never measured the Timken bearing extension but it's been said here it's more like 1/8". So it's probably a good idea that I relieved the axles as I did.

Good thing I don't do this for a living - or my employer would go broke (or fire me first). I like to take my time on these things, esp when it's the first time I've worked on a particular vehicle. And when it's a holiday anyway.

I took photos of each brake assembly before tearing them down, and I'm glad I did. Saved me a lot of grief figuring out which part goes where. As it was, had to search for about 20 minutes for my older brake tool (the new set of brake tools I got at Harbor Freight are ok but didn't work too well on installing the upper springs).

Should be done by the time the fireworks start going off.

Got the axles installed.

Got the brakes installed.

Powder coating of diff cover in progress.

Taking a break for dinner while the cover cools, gonna put on a third coat and that should do it. Except for the bolts.

The downside: Axles seem quiet and all good so far.

But the right rear brake is still grabbing, on hard braking.

I'll have to pull that wheel again and look at it. Minimum, bleed the brakes, and maybe replace the automatic adjuster mechanism. Might need a new piston on both sides. MIght be the left rear brake that is the problem. At this point, don't know.

Will also look at the front brakes - they should be doing most of the braking, anyway.

A few hours later... (family function intervened)... re-adjusted parking brake... now both rear wheels skid equally on hard braking... progress... decided to get same brand shoes (Wagner) for front brakes. Checked out rear brakes/seals. No sign of leakage yet... did one front wheel... went quickly enough... gonna do other wheel, then test drive...

Drove ok, rear wheels still skidding before front. I guess this van is just tail-happy. Will still bleed brakes when I get a chance, but they don't feel spongy so it's probably ok. They don't pull to one side or the other, and the braking seems to be firmer than with old shoes (which were el cheapos anyway).
These are now Wagner "Themo Quiet" which cost twice as much as the bargain brand and seem to be worth it.

Or anyone.

Not having much luck locating new axles for this van.

It appears they are an odd length. The axle guy came up blank.

I measured them at 28 spline, 31-5/16" long, 5 lugs on 4.75 bolt circle. Bearing surface is 1.399" diameter. Axle guy says this is a passenger car type, except for the length. I think I could get Moser to custom make some, but it would probably start at $240 just for the axles - no studs, seals, or bearings.

Anyone have a different source?