I bough a set of 2.93s for my 70 8.2 10 bolt to replace my stock 3.42 just to have a more comfortable cruising RPM but I'm having a small issue trying to install these gears The pinion came original with a shim a bit thick and after install it I found that the pinion was too deep so replaced this shim with one thinner, the pinion deep was better but still too deep so I proceed to remove the shim and let the pinion bearing without shims, the result was even better but now I've an issue with the pinion having play even after being torqued. I tried adding shims on the pinion sleeve but I think it didn't make any difference Any suggestion?
if your having to run with no shims under the bearing or under the race.......does same thing just under the race it's easier to change depths since not having to urge bearing off.........somethings not right. are the races all the way seated into the housing with nothing under them.....dirty tiny metal to push the race towards the ring gear causing a reading like too thick of shim?????
I didn't change the races and all of them were working fine without noises or lack of adjustment before start the gears change Usually when I have done this in the past I try to adjust placing shims on the bearing instead behind the race because I was told that race shims usually is for different adjustment, is this true? Maybe I should go back and check how many shims I currently have on the pinion race, but if this doesn't help with the pinion play what kind of adjustment can fix it ?
What was your pattern with the original shim,and then the thinner shim? What are you setting your backlash at each time? This is where pictures would be helpful to look at the pattern.
a shim between the rear.....larger......pinion bearing, or between the housing and the race of the the rear bearing has the same effect. they both control the location of the pinion in its depth. the shim under the race is more easily exchange than one under the rear pinion bearing, unless you have a checking bearing made that easily slides on and off. now the same shim can not be used under the race as under the pinion
That 68-70 Buick 8.2” also has a very large inner pinion bearing,so the pinion shims are larger diameter than your typical 10-bolt or 12-boot shims. Trying to shim behind the race would require a very large diameter shim. Is the oil deflector still behind the original race? If that is removed,that would cause the race to go deeper into the bore,but would also require a thicker pinion shim. The shim kits that I get for that pinion are Ratech 1102. To not have any shim in there at all signals something is not right. I would like to see pictures of the pattern,and what the backlash is.
Got a dumb question but did you get a carrier with this ring and pinion? If you are trying to mount the 2.93 on a 3.42 carrier posi or non posi ... it will not work... WELL it could work but will be WAY to far to the right or left in the case causing the axles to engage too deep on one side and too shallow on the other. If you do have the correct carrier combo with the correct 2.93 ratio then the oil sling as Brian pointed out and even shims running up on the pinion shaft will be your headache for sure. Most of the Buick 8.25 68-70 are .028 shim and do not deviate too much ... And with Brad and Fabcraft gears he even kept that a same deal with the gear set-up... They did pretty good machine work on these rears... FROM what I have experienced in the diffs I have set-up over the years. Jim J D
I'm using my 3.42 carrier but one thing that I noticed is that using these gears the carrier bearing spacer of the left side doesn't fits like the carrier is too on the left side with this new ring. I was told by @BrianTrick that these gears are for a 70 like mine so I'm not sure if this could be the issue The problem is that the carrier / bearing are too tight that I think I don't even have backlash. I'm going to take some pictures today and post them I think the larger shims for the left carrier bearing can work on the pinion race, I'm going to check today
Yes,the gears I sold you are out of a 68 GS rear. They will fit the 68-70 Buick 8.2” rears. Now I see where the issue is. It is not with the pinion or the pinion shims. Like Jim said,you should be able to use the existing or original shim for the pinion bearing. The issue is with the 3:42 posi unit. The flange for the ring gear is positioned further to the right,or the center of the carrier. The carrier used for the 2:93 would have the flange positioned further to the left. I do not have a correct posi unit,but I have a non-posi unit that I can send you,no charge. It would at least show you the difference in the carriers. There are a set of 2:56’s attached to it. You can have those too.
If you're interested in selling the posi unit with the 3.42s please let me know - I have a 700r4 trans in my car and those gears would work nicely
this is what I love about this board, with in a few post problem found. everyone willing to share there information, knowledge, and experience. guess I never knew the 8.2 were that sensitive to carriers. I know it wasn't the correct right thing to do on an early build 8.5 for my car, but I was able to run 4.10s on the original upper 2 carrier, it was way over, but was able to shim everything up correctly.
NO you can not use that carrier with the 2.93 gears. If it is a Stock posi Auburn your going to burn up the carrier cone as the one axle shaft will not totall engage both pieces of the side gear. So now you have found your problem... That is why nothing is fitting correctly. The carrier shims on the driver side are 12 bolt Chevy type and the passenger side are regular 10 bolt 8.2 8.5 etc. I sell New carriers for the 2.73 AND 293 RATIO. cARRIER BREAKS ARE AS FOLLOWS ON 8.25 Buick 1968 -1970 2.56 (ALL BY ITS SELF) 2.73 2.93 ratios 3.23 3.42 ratios 3.64 - 4.78 ratios Hope this helps. Jim J D
I don't think that could be the issue since my rear is a 3.42 non-posi Yesterday didn't have time to work on the car but tonight I'm going to spent some hours and take pictures, maybe that could help to figure out what's going on Old pic of old 3.42s
Posi or non-posi,you can NOT use the carrier from the 3:42’s with the 2:93’s. You want some 2:56’s? I’ve got those with the matching non-posi carrier.
Does the 2.56 carrier will work with the 2.93s? because according to the post of @monzaz it won't. I thought the 3.42 carrier will work just with the right shim combination
picture of what the problem is from series to series your 3.42 is the right unit... the 2.93 would be one of the left units. stepped down flange ... as the pinion gets more teeth the diameter increases and in turn the ring gear has to be moved over in the case to engage properly ...IN GM REARS. FORD Mopar early third member rears just keep making the ring gear thinner or thick to compensate for the pinion increasing or decreasing in diameter. The thicker the ring creates more mass you have to spin with the pinion maybe why GM did what they did with th e series to keep the ring gear weight fairly equal in mass at least in the stock gears. When you get to 4.88 and steeper gears just have to keep getting thicker as there was hardly any pinion diameter at this point. Jim
open carrier has a side gear that is 1" long spline ONE PIECE - The limited slip Original BUICK Auburn unit the cone hub and the side gear are stacked on top of each other and are both splined for the axle 28 spline. IF you move the carrier too far left or too far right .250 you could have no side gear engagement in half the spline of the carrier causing the unit to burn itself up. I am not saying in a MAD MAX world you can not make it work... Your just rolling the dice that your driving the axle with 3500# and on ly 1/4" or less axle engagement on one side. so... again as i always say... It IS your car... do what you feel you want. were just here to give you the info you need to make the best guess. This is how I never run out of work... sooner or later it will break and some one has to fix it right. more than 50% of business for me is fixing goofs by others. Jim
Sometimes I can't understand why our Buick are so complex I do my best to keep my car all buick but since I started messing with the gears I have to confess than more than one time I have considered the option of swapping rear end for a Chevy 10 or 12 bolts and call it a day but would be a shame do that on an all matching numbers car with less than 50k miles I'm sending a PM to @BrianTrick to see if that carrier is still available
