When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Thinking of starting the gear swop in my rear. Can anyone recommend a good complete kit with bearings, seals, Sims, and gaskets? it's a 10 bolt rear original to the car. A 74 Omega.
Railguy
I bought stuff from Randy's Ring and Pinion many years ago. I have also bought bearings and seals from the local auto parts store. You will likely have to go through a specialty shop like Randy's for shims but bearings and seals are readily available.
I bought the Richmond install kit for less than $100. Has all the shims bearings seals gasket for the job. I made bearing race installation tools from some Brazilian cherry I had lying around. It's an extremely heard wood and worked great. I should have it done in few more days if everything goes well.
Railguy
I have the gears in temporary.1 st time the pinion needed shimmed the marks were to far to the out side of the ring didn't take any pics .So I put in 3 shimes about .0118. Then it looked like this. 20151228_113427.jpg
Did you load the ring gear when you turned the pinion. Make sure you backlash is correct. The pattern you are showing is not right.
Once you have the backlash set correctly, run the pattern again. It should mash out to give approximately 50 % or so coverage on the tooth both side to side (depth) and toe to heel. You can look on the internet for some pictures of patterns of properly set rears.
Last edited by bobus8; December 28th, 2015 at 04:49 PM.
Here is the csm from 1974. Pattern does change between years. I used to cut 80 inch ring and pinions and it was the same thing when we tested them. You want your pattern to run center to toe.
Did you load the ring gear when you turned the pinion. Make sure you backlash is correct. The pattern you are showing is not right.
Once you have the backlash set correctly, run the pattern again. It should mash out to give approximately 50 % or so coverage on the tooth both side to side (depth) and toe to heel. You can look on the internet for some pictures of patterns of properly set rears.
By load the ring gear, do you mean pre load carrier bearing? I did that then set the backlash which was .032. I set it to. 008. Then when I checked it it was way out . So I pretty much just started over. I changed the pinion depth 3 times. I didn't check it after the third time. I had enough for one day.
I've never done this before. The thing that concerns me is how fine the contact area is it's more of a line then an area. These are used gears I traded for some parts. The guy I got them from got them from someons eles he said they came from a mid 80s grand national with 15-20 k . Which looks believable from the condition of the clutches. I got the whole l s differential in the deal less the spring in the middle which is why he didn't use them. He couldn't find the spring.
Railguy
By load the ring gear, do you mean pre load carrier bearing? I did that then set the backlash which was .032. I set it to. 008. Then when I checked it it was way out . So I pretty much just started over. I changed the pinion depth 3 times. I didn't check it after the third time. I had enough for one day.
Railguy
When you run the pattern, use a big screwdriver and wedge it against the carrier next to the ring gear or on the outer edge of the ring gear so that when you turn the pinion, you are putting a load on the face of the teeth. This will mash the marking compound out and give you a good read of the setup.
It wasn't real clear in the pictures but the drive side looked like the contact was touching at the edge of the heel. If this is what is actually happening, then the pinion need to move deeper into the ring gear.
Be sure to set the backlash each time you reset the depth on the pinion.
If the pattern looks good but it is slightly off from center toward the toe side, it should be close enough. I don't like mine to be off center towards the heel side but if you aren't running slicks, it should be fine either way.
The pictures that coppercutlass posted should give you a good idea of which way to go.
I'm thinking that there is a variation factor at play here.When cutting all the holes that receive the bearing races it requires a lot of different set ups .The holes that receive the pinion shaft races are cut from opposite sides if the are off the shaft is off that's why there's shimes if its angled up or down this can't be shimmed only side to side can be.In the pic under acceptable patterns "page 14" it shows the pattern next to the edge this is the only reason I can think of for this . Also I bought the gears and carrier used from a guy who got them from someone else so there's always the possibility that pinion does not go with the ring .I trust the guy I got them from but I don't know where he got them.
railguy
I wouldn't think there is a problem with the housing but I have seen warped housings. The pattern you have showing in the pictures isn't close enough for the rear to live. Since you don't know the history of the rear, there could be a compatibility problem between the ring and pinion but I would suggest you try this before giving up.
Disassemble the rear and take the pinion shim completely out.
Put the big pinion bearing back on with no shim and leave a space about .125 of an inch between big bearing and seating face of pinion.
Reassemble the pinion and then put the carrier in.
Start tightening the yoke on the pinion to draw the pinion into position while checking the backlash and running a pattern after each time you tighten the pinion yoke a little.
If the rear can be set at all, this method will get you into the ball park without constantly disassembling and trying another shim.
If it does come in, disassemble it and measure the space remaining between the pinion and the big bearing with a feeler gauge. That will be your starting shim for the next try and getting close to the finial setup.
I wouldn't think there is a problem with the housing but I have seen warped housings. The pattern you have showing in the pictures isn't close enough for the rear to live. Since you don't know the history of the rear, there could be a compatibility problem between the ring and pinion but I would suggest you try this before giving up.
Disassemble the rear and take the pinion shim completely out.
Put the big pinion bearing back on with no shim and leave a space about .125 of an inch between big bearing and seating face of pinion.
Reassemble the pinion and then put the carrier in.
Start tightening the yoke on the pinion to draw the pinion into position while checking the backlash and running a pattern after each time you tighten the pinion yoke a little.
If the rear can be set at all, this method will get you into the ball park without constantly disassembling and trying another shim.
If it does come in, disassemble it and measure the space remaining between the pinion and the big bearing with a feeler gauge. That will be your starting shim for the next try and getting close to the finial setup.
I didn't mean there was a problem with the housing at least a problem that couldn't be dealt with. I meant that is the reason for the pattern being on the edge of the Ring.
anyway I just took .020 Out and paid more attention to the preload on the pinion bearings. I was just guessing before. I checked it and I saw a pattern that was pictured in the instructions which is its to close. So this time I'm talking out .026. Hopefully I'll be to far away then I can start to dial it in.
Thanks Railguy
I think where I messed up at was I used the old bearings to set it up . Which is what a few videos said to do. You take the old bearings off and sand the is side of them so they slide on and off easy .then you shim them till their close . When you get them close you put the new bearings on and go from there . I didn't think it sounded right . When I put the new bearings on they were so far off that the pattern was not on the chart.
I think I got it close now. The US Standard instructions say when using used gears go by the coast side not the drive side. That doesn't sound right either.
here is pics of what I have now the backlash could be .004-.006 tighter.Can anyone tell for sure if this is right?
Also instructions have 2 GM 8.5's new cut and old cut.There's a small difference in the backlash.Anyone know the the difference?
railguy
[QUOTE=Railguy;882891]
here is pics of what I have now the backlash could be .004-.006 tighter.Can anyone tell for sure if this is right?
Also instructions have 2 GM 8.5's new cut and old cut.There's a small difference in the backlash.Anyone know the the difference?
railguy
This pattern is what I consider to be perfect. The contact will walk further down the tooth under heavy load. (Acceleration under power)
As far as backlash goes, since you have the proper pattern, you obviously have the right backlash. It Should be in the .010 to .012 range or at least real close to that.
In the older vehicles, I don't like to run anything less than 90w but be sure to get the posi additive from a dealer.
This is the oil I got. The other pic is of the bearing race installation tools I made.
I set the backlash at . 006. The instructions I have said .003-.006 for the new cut gears and. .006-.012 for the old cut gears I didn't know which I had so I set it at .006 which is at the top one setting and the bottom of the other.
Railguy
This is the oil I got. The other pic is of the bearing race installation tools I made.
I set the backlash at . 006. The instructions I have said .003-.006 for the new cut gears and. .006-.012 for the old cut gears I didn't know which I had so I set it at .006 which is at the top one setting and the bottom of the other.
Railguy
For some reason, I thought you were using a used ring & pinion but like I said, the pattern looks good so....
Valvoline is what I normally use and since it said it's for limited slip it should be ok. Smell it and see if it is extra stinky. That will tell you for sure that it has the right additive. You can always add more the friction modifier later if you hear any chattering when turning corners.
Took it out for a test run yesterday as far as I can tell it's fine. No noises . A lot more power. It wasn't bad before but better now. Little wheel hop in 1st . Bought a set of traction bars at Carlisle last year. I guess I'll work on that next. The wife says she's not going to ride with me anymore. She will.
Railguy
December 15th, 2015, 10:06 AM
