[Lobito's65Cat]

I need to find rear bearings for my 65 Cat, havent started looking to be honest but since im at work and wont get out till seven i tought i might ask you guys. Thanks in advance.

[pontiacjeff]

One more thing, CNC machined brgs now days are much better tolerances than the old stuff. I think the problem is the grease. It's too thin. The old brg grease was much thicker.

[Hitman]

How much did you guys pay for your bearings?

[Deadhead]

In my case I have owned the car since '83, & before that it was my grandfather's, so it is known. Unless it was changed early in its life, which is unlikely, I would know about it. I personally put over 50k on it without changing Brngs, so that is a 5X improvement over currently available parts minimum.

Probably some forbidden substance in the old grease.

[Deadhead]

Recently the ones for our F/S were backordered at the smaller parts stores & I think Ames. Took some looking. Probably should have ordered 2 sets. Scary that that part would be hard to find. Napa is Japanese. Could be worse.

Good advice on the shop makes the Napa option even better.

[AROWHED]

Meanolgoat, are you absolutely certain about that? I don't beleive a 65 GP has a different rearend housing (as far as axle bearings go) than any other 65 fullsize. I own a 65Gp and have put replacement axle shafts into it's rearend that I pulled from a 68 Catalina.
Hollanders even says axles shafts are fully interchangeable between all 65-70 fullsize Pontiacs.

[Lobito's65Cat]

I need to find rear bearings for my 65 Cat, havent started looking to be honest but since im at work and wont get out till seven i tought i might ask you guys. Thanks in advance.

[meanolgoat]

I paid about $60.00 each, for the Timkin RW508BR

[Deadhead]

$43 Ea. for NAPA Japa.

[Deadhead]

I think we just completed a study on the evolution of product quality.

[pontiacjeff]

The other brgs are for the brg retainer 10 bolt in 69-71 GP's and other Pontiac 8.2 rears.

I agree with the quality issue of new parts. But, how does one know the axle bearings are original on a car that is almost 40 years old??? Esp if one has only had the car 2, 3, 5, even 10 years?

[pontiacjeff]

65-70 All Pontiac FS (incl. 65-68GP) rear bearing is p.n. RW508BR, industry-wide. Some mfg drop the "RW".

It really doesn't matter whose brg you use, they all last about 10K miles. It was a bad design having a sealed brg in that application. All the grease "sealed" in weeps out and they run dry. You can extend the life by acquiring a hypodermic grease fitting and squeezing some grease b/t the outer lip of the seal and the outer race every 3-5K miles. That could go on indefinately, but every time you insert the needle, the outer lip gets a little looser, and is more likely to leak...

Stuck in Dallas Tx last May with a broken posi and a bad whl brg, I was forced to improvise. The 4.11 posi was swapped for a 2.73 open in the pits, but the axle brg presented more of a problem. So, to extend it life and get home, I removed the inner lip seal (inside face of brg) and loosely packed the recess b/t the axle oil seal and the inside face of the brg with whl brg grease. This insures a constant, greater volume of grease to lube the brg. The only prob so far is slight weeping of grease around the OD of the brg. It's not even enough to make it onto the backing plate. I'm sure this is due to windage, not actual leakage. A small hole in the top side of the axle tube with a 1/8" NPT nipple fitting, some vacuum hose and a check valve should eliminate any weepage around the brg. (I have yet to do the last mod, but plan it soon.) It's my hope that the next set of brgs I buy will be the last.

Arowhed, next week... no later.

[george kujanski]

I find it REALLY hard to believe that sealed axle bearings only last 10K miles. I never had to replace axle bearings back in the day......

The bearings also don't need a lot of lubrication. Sure, they need some, but not much. Rolling friction compared to other types is very low, low friction = low heat generation. The lubricant helps lower friction even more plus keeps the seal lubed. What will kill the bearings are contaminants getting in there or water, which will cause rust on the balls and races, and away you go. Overloading the bearing will damage the balls and races also. Excess heat generation will damage the lube and seals; excess heat from dragging brakes, etc. could do it. Sealed axle bearings should easily last 100K. If not, something else is going on.

George

[mr67gp]

My experience has been the same as Deadhead. Well over 100k on rear axle bearings has been the norm for my over a half dozen '65-'70 cars. My '67 Bonnie agon has 146k and the axle bearings are now gone.

[Deadhead]

Got mine quickest at NAPA.

[AROWHED]

That is a real good point, George. I as well was always impressed by how long an alternator front bearing can last, in such temperature extremes, tight belt tension, and constantly varying RPM all acting agaisnt it.

But then again, I have fallen prey to a failed sealed rear axle bearing on my 65GP. Noticed a low rumbling sound one day, so drove 2 miles back home, then found the damage. I have no idea how many miles the bearing had prior to failing. But when it did, it forced the press-fit inner bearing race to spin on the axle shaft, destroying it as well. Kinda hard to find 65-70 fullsize Pontiac axle shafts in the salvage yards anymore...or any other part for that matter.

I puleld the rear end off a junk 65 Bonneville a couple months ago. As a test, I pulled one axle shaft out, then removed the axle shaft oil seal from the axle housing. Next, I pried out the sealed axle bearing's INNER oil seal, the one that would face the differential. Then re-installed that axle shaft, bolted a tire on (with no brake drum behind it), then stood the rear end up vertically on that tire. I let it sit that way for about a month, to see if the gear oil would migrate through the bearing and past it's remaining outer seal. Short answer is: Yes, the oil got through it, but it was not a whole heck of a lot. And it was a pretty well used bearing, too...but still had some miles left in her, though.
So the next test will be to try the same in a car that's being driven, with a brand new axle bearing modified as above, to see if the gear oil will lubricate it enough to keep it alive, while not leaking out onto the brake parts excessively.

[Deadhead]

Until I changed out the case, my '66 Bonneville w/ 100k on it had the original rear bearings & seals. Never made a sound, never leaked, never babied. Go figure.

[meanolgoat]

Be careful with the rear axle bearings. When I replaced mine on my 65 Cat Convertible, I found out I had a 65 Grand Prix rear-end and the Bearings were larger (and more expensive) then what was in the standard Pontiac rear-end. I ended up cross-reference the part number directly off the old bearing to get a new one.

[Stuart]

NAPA or any good local auto parts store should be able to get them for you. If it were me I'd just take the axles in and have the shop install them, since you need a hydraulic press to remove the old ones and install the new ones.

[george kujanski]

Regarding sealed bearings: a good friend of mine from my days at Motorola Automotive was the mechanical engineer on the alternator product. He is still amazed at how little grease is required to make the bearings live. For example: the front beaaring in an alternator is a sealed bearing with very little grease. It lives a very long time at high speeds in the underhood environment. Pretty amazing, I think. The axle bearings run pretty slow by comparison. Say with most tires they spin about 750 revs/mile so at 60 MPH that's 750 RPM. The bearing is spinning at 375 RPM; no big deal.

George