Oldssupreme

Can anyone tell from this photo if my mechanic pressed these bearings on far enough along the axle of my 72 cutlass supreme? I can move the seal with my hand down to where the rusty part begins near the retainer plate. I have not tried installing yet as i don't want to damage the seal if it is not right. thanks for your help!
Chris

Allan R

Looks fine Chris. You can dry fit the axle without any problem. Just have to tug it to get it out is all. Here's a pic of the new bearings on my axles before I cleaned them and installed them.



AFTER - note: Also replaced wheel studs. Removing the old ones makes clean up of the hub much easier.

Oldssupreme

Thank you so much allan! Chris

monzaz

What brand Axle Seal do you have on your AXLE SHAFTS pictured? Jim Mitschke

monzaz

Your bearings are on BACKWARDS take them back and get it done over. Tell him he owes you NEW bearings and seals as I doubt he will get them off with out ruining them. Sorry to tell you the bad news. Jim Mitschke

The taper is going the WRONG WAY!!!

This is why I HATE THESE BEARINGS TOO.... The old Bower bears were so much easier they were none directional and the end play was not a super critical deal. Jim

Allan R

Jim, I don't know the brand. This was subletted for install. Is there a problem with them? If there is I need to know because they're installed but haven't been run.

I didn't see a taper on the bearings, they appear to be square formed on the ends.

MDchanic

Just to clarify what Jim pointed out, look at the grooves on the bearings in these pictures:


Groove toward the middle:





Groove toward the outside:





Groove toward the outside:



- Eric

Allan R

Ok, now I see it. So basically this would run the bearings dry fairly quickly? Is there anything you see with the axle seal?

Oldssupreme

Jim and Eric, could you clarify, which is the correct way? Should the groove be pointing toward the middle or should it be pointing toward the brakes?
Thanks so much for your help!
Chris

MDchanic

Middle Bad.

Outside Good.

- Eric

Oldssupreme

Ok, so the taper should be getting smaller pointing toward the middle?
Thanks guys,
Chris

cdrod

This thread is very timely for me as I'm assembling my rear suspension and the axle bearings have me concerned. I spoke with Jim (Monzaz) about the tapered bearing with separate cup (race). The original bearings were a single unit with a captured race, so I'm concerned about end-play. Here are some pics of my axles, the cup is not shown because it is still in the axle tube. Is this the correct seal? I can't see a part number. I can slide the seal up and down about 1/4", the bearing doesn't seem to move as far. Here's the million dollar question (for me anyways) - how do I set the bearing preload? I don't see how to make sure the bearing depth is right so it's riding all the way into the cup (race). Seems like the bearing could "walk" outward and only ride half-way in the cup. This is further complicated for me because I'm trying to fit '01 Blazer rear discs for rear brakes and the Blazer backing plate is much thicker than the stock drum backing plate so I will need to fabricate some kind of spacer to fill the gap.



Axle seal all the way inboard


Axle seal all the way outboard


Blazer disc brake set-up

Oldssupreme

Ok, thanks to all of you who pointed out the mistake. I bought new bearings and lock rings and the mechanic did not charge me anything.... So were good there. However, can anyone explain the correct way to install these back in the rear? The service manual just says "install rear axles".... Thanks so much again guys, you have been great! So much help!
Chris

Allan R

There's also a gasket that goes in front of the bolt plate.
To install the axle, insert it into the tube till it contacts the carrier. Rotate the axle very little till the axle splines slot into the carrier. Then simply push firmly in till they are fully seated. When you do up the bolts that will fully seat the axle. After that it's just a matter of filling the differential to the proper level. I prefer to use 80/90 weight conventional gear oil. If you changed to a limited slip carrier, be sure to add in the posi additive around mid fill. Without limited slip? Just fill to the proper level.

Fun71

In addition to what Allan posted above, when you insert the shaft into the tube, you have to get the spline end into the hole in the side of the carrier. The hole is aligned with the center of the axle tube so you have to work the shaft around until you get it aligned with the hole.

Oldssupreme

thanks guys! can anyone post a pic of the area between the backing plate and the axle tube/seal area so I can see what that looks like when all is in place? Can you see any of the seal or does it totally seat itself when you tighten the axle flange bolts?
Thanks again!
Chris

Allan R

Chris, the gasket is totally hidden. You can put a light dab of permatex on one side to hold it to the axle tube side and then slide the axle into place. Honestly I never thought to take a pic of that. I noted that the CSM doesn't have a picture in it so that's no help. I bought my gaskets from ILT. You need 2 of them: http://www.ebay.com/itm/1964-72-GM-R...-/370781354917

cdrod

Allen:
Do you really need the gasket between the axle flange and the backing plate? The axle seal has a rubber lip on the outer edge that seals to the inside of the axle tube when its pressed in by the retainer. I always thought these gaskets were for the C-clip Chevy rear ends that don't have the retainer to hold in the axle (and the seal).

I'm still waiting for someone with more experience to answer my questions about my bearings and seals. Am I good to go here or do I have the wrong parts as well?

Rodney

monzaz

Ok first off the alxe bearing and seals are all installed correctly. You do have the race? Correct? In the axle i suppose still?
NEXT - blazer brakes. YOU are asking for headaches here. BUT if you insist to do this you MUST use shim material to pile on top of the seal so the retaining plate will push against the shim material then pushes the seal against the bearing and then the bearing into the race in the housing.

THIS IS critical to get correct and will take some doing on and off etc.

PLUS it may still leak. Have fun with that one. JIm

J D

cdrod

Jim:
Thanks for your reply, and I share your concern about leaking; I don't want a great looking car with a constant oil leak. I've think I've done my homework here; I researched several rear disc set-ups, including Vette C4, C5, Camaro LS1, Cadillac, etc. I wanted to stay with factory parts rather than aftermarket stuff so replacement parts could be purchased at any auto parts store. I really liked the Blazer set-up best because of the integral parking brake shoe, same size wheel bolt circle, and it uses an aluminum caliper. I figure if it worked for the Blazers, it should work for my Olds as long as the seal is held tightly into the axle tube. Here's what I've done so far:

I've removed the stock drum backing plate and added a 1/4" spacer between the axle tube and the Blazer backing plate to center the rotor in the caliper; I've turned down the axle flanges to fit inside the Blazer rotors and shortened the Blazer parking brake cables to attach to the factory drum brake locations on the frame. Next on my list is to fabricate a 5/8" thick, "split donut" spacer from aluminum plate to fully push the seal into the axle tube using the stock retainer.

But I'm still concerned about the bearing pre-load. With front (tapered) bearings you tighten the nut to 30 ft.lbs. and back off 1/2-turn and hand tighten to the nearest cotter pin hole in the spindle. The CSM says the end play should be .001-.008" Using the stock rear bearing with cylindrical rollers you didn't need to be concerned with pre-load or end play because the bearing was fixed to the cup (race). With the new tapered bearing and separate cup, I have no idea how much play the rear bearing should have.

Here's my math on this: The combined thickness of the 1/4" axle spacer and the Blazer backing plate is just over 5/8" (0.64"). The stock drum backing plate (which has been removed) was 0.1" thick; so with my 5/8" donut spacer there will be approximately 0.115" clearance (end play).
Is this too much?
Does the bearing need to be tighter?

Thanks in advance for your reply.

Rodney

cdrod

I've done a trial-fit of my rear axles and have the bearing and axle seal pressed all the way into the axle tube. Using the stock brake backing plate and retainer I have about .035" of in and out end play of the axle. Is this acceptable? Is there a way to reduce the slop. The front wheel bearing tolerance is much tighter. Just want to do this right the first time. Thanks!

Rodney

monzaz

It is tough call as I did not get a chance to see how much play is in the bearing it self. When you twist the bearing in your hand before installation see how much play there is... THIS IS HOW much end play it will have in the housing...

So it all depends on how well the bearing is built in tolerance between the channels the bearing rollers run is the end play tolerance you will get when the bearing is installed...NO MATTER how tight you push the seal into the housing.

So .035 could be ok...But i remember the days when there was NO END play at all ...

Jim
J D

Octania

I don't think any appreciable end play is good for a tapered roller bearing. Is that how pinions are installed? Hell no.

I was wondering what's with the tapered bearing. Seems to me like you need the taper the right way around or else the axle is not trapped and could just slip on out of the car when you round a bend. Then, you need the retainer plate to press/ hold the seal in the right place which then holds the outer race in which then holds the axle in. So, the axle cannot move in or out because it is well secured both ways.

Re-engineering stuff is not all that easy.

cdrod

Is it possible that the inner bearing retainer on my axles needs to be pushed further? I'm talking about the large metal donut that keeps the bearing on the axle shaft. Using feeler gauges, I have approximately .067" between the bearing and the inner retainer (as marked by the white lines in picture). Should there be that large of a gap here? Do I need to take these back the machine shop and have them pressed further? The race(cup) and the seal are all held tightly in the axle tube when the outer retainer is bolted in place; so it seems the only logical explanation for the end play is the inner bearing retainer. I'm hoping Jim chimes in again on this. What do you think Jim?

Fun71

It's hard to tell from the picture - is the gap between the retainer and the cage, or is it between the retainer and the inner race?

From what I know, there should be no gap between the retainer and the inner race; it should be pressed so that it is in contact with the inner race. The cage will have some "looseness" to it so there may be a gap between it and the retainer.

cdrod

Fun71:
I took a closer look at the bearing assembly when I got home from work today. It's definitely the roller cage that is moving causing the .067" gap shown in my previous picture, and it doesn't look like there is any way to reduce the end-play. I guess I'll have to live with .035" play.

cdrod

I'm revisiting my rear axle end play issue because it's causing issues with the rear disc brakes. The excessive endplay allows the rotor to push the brake pads into the caliper, away from the rotor which delays the application of the rear brakes until they take up the slack. I think this is called "knock back". I've only driven the car a few miles since setting up the rear end, but the end play seems to have increased. Back in 2014, I had about .035" of end play (in & out looseness); now I'm measuring .039" of end play. I ordered new bearings to evaluate the endplay before installation. My first set of bearings were Timken (I think Set9), this time I ordered National A9 bearings and immediately I noticed the outer race is attached to the National bearing where the Timkin bearing has a loose outer race. Using a dial indicator on the work bench I measured the the endplay of the National bearing to be .013"; .005-.010" is recommended so this is little out of spec. I also have a ridge inside the axle tube at the top of the housing. The old Timkin bearing race will slide past this ridge when inserted by hand, but the new National bearing will not go past this ridge.

I'm still a bit perplexed by the tapered bearing vs. bower bearing differences. Am I correct that the taper style bearing should be installed with the taper facing inward, toward the pumpkin? Since the bearing tapers toward the middle, isn't the bearing retainer ring unnecessary because the outer race becomes the retainer?

I'm hoping Jim (Monzaz) chimes in on this post. I have to figure out a way to reduce the axle endplay. Here's some pics

Rodney


New A-9 bearings from National.


There is a raised ridge on the upper half of the axle tube where the outer race sits. Should I clean this up with fine emory cloth?


I think this is the outer side of the bearing-see the grooved line around the top perimeter.


I believe this is the inner side of the bearing.


The existing Timkin bearing, the outer race is not attached.

Fun71

Jim has posted several times that there is a difference in seal thickness that has a significant impact on the axle end play. Maybe search for the seal number to find his posts about that.

monzaz

Seems National has been having some better seals or old SKF 712146 ( 16735 ) I think is the number for SKF..?? ) Jim
Timkin is making theirs in Taiwan now so they are no good.