8.2. Buick Carrier Gear Pattern

[70supreme]

I am in the process of re-installing the carrier into my 8.2 Buick rear end and have the backlash set at 0.007" and I am not getting any distinctive gear pattern, see picture attached. Any advice on how I can confirm that this is setup properly or how I can get a distinctive pattern?? It is cold in the garage as it is winter here, not sure if that affects the gear marking compound. Also these are the original gears that was in the rear end previously (3.23). Any help is appreciated as I would like to get this completed over the Christmas break. Thanks.

[monzaz]

Sorry for the delay Holiday stuff.
You need to squirt some gear fluid onto that pattern to make the pattern come through better. NOT a ton at one time...
To me it appears what you have looks pretty close.
The oil will make the yellow compound move off the tooth where it meshes revieling the way it hits.
Jim

[monzaz]

If these were GOOD running original used gears - and all you did was a re bearing of the rear...USE the original shim and the back lash is going to be wider than .007... more like ..009...DOES not seem like this is a huge difference...but you would be surprised what it can do.
Making sure your carrier preload is tight too helps keep the carrier true.
You should not be able to pull the carrier out of the cavity / saddles by hand ....YOU SHOULD need to pry it out with a Machinist J bar.

Just tips
If you are obviously destroying the shims your are way too tight.
You should have to tap the shims into the cavity with brass and a little 1# ball peen hammer.... and remember the shims need to be parallel to the carrier saddle so they have a chance to slide in true.
The factory used case spreader... I prefer a regular installer not to use this as they tend to spead the case too wide and either putting too much preload on the carrier and or destroying the case.... so if you just use the technique of pull out by hand too loose and not denting or smashing the shim pack too tight method...SEEMS very gray area...But works.

[70supreme]

Thanks Jim I am back out in the garage tomorrow and will try a little gear oil. Bought this rear end for my 70 Cutlass and the pinion nut was loose when I received it, so I took it apart to check the condition of the gears and bearings (all of which appear to be in good shape). I did break one of the factory shims removing the carrier, but have installed new shims using a home made flat bar tool to tap them back in place (difficult to get them in so preload on bearings should be good). If I were to set the backlash to 0.009", how thick of shim would I have to remove from the left side to place on the right side?

[monzaz]

It is sometimes a trial and error. if you have .007 adding .002 to the pass side and removing .001 -.002 should do it. BUT that depends on how much preload you have on the carrier to depend how far it will actually register on the dial indicator. (hope that makes sense.) MATH IS EASY IN A PERFECT WORLD....but reality is something totally different.
You should really get proper steel shims we have them for like $7.50 does both side .300 of shim 2 .100 s and the rest are thinner to sandwich between to make what ever thickness you would need..
Jim
Shipping is usually more expensive than the part...

[70supreme]

I am using the shims that i ordered from you. I now have the backlash set to 0.009" and I am still getting a similar pattern, it seems to be removing the compound from the entire tooth of the gears (not that half moon shape I see in everyone else's pattern). I also used the squirt of oil as suggested.

[monzaz]

looks good to me . Button it up. Or you can keep putting some gear oil on till you get a absolute pattern with out the frosting effect .
I always put my marking compound in a little plastic little mixing dish and some gear oil mixed... thins it out and also makes it go further.
As is it looks pretty good.
Jim

[70supreme]

What should the pinion preload be with the carrier installed (axles not installed)?

[monzaz]

Grey area. ---- If you can pull the carrier out by pulling the ring out of the case then it is too loose. IF you are destroying the shims tapping them in it is too tight. A 'J ' machinist bar should have to be used to pry the carrier out of the bearing saddles.
THERE IS a GM spin test BUT that is done with the pinion out and axle out etc. one and one half spin...IF seems very goofy to me as someone could spin harder and another less. ???
That is why IO do it my way. Shims tightness...remember the factory uses a case spreader too. IT should not be necessary to use a case spreader to set up a rear. BUT the shims need to be pretty tight...Your going to have to tap them in with brass or other soft metal
JIm

[70supreme]

I believe the preload on the carrier bearings is good based on your comments, what should the preload be on the pinion (don't want to over crush the crush washer)? Online it says 6 to 7 in-lbs for used bearings/gears, but wasn't sure if it should be more with the carrier installed.

[monzaz]

yes about 10 inch lbs of spinning torque...obviously not a standard click torque wrench.
remove the in out play on the bearing and work the nut against the crush sleeve till the achieved spin is correct.

[70supreme]

Thanks Jim, I have the pinion preload set at 10 inch pounds.

[monzaz]

ok, get the carrier in there if you have new bearings on the carrier the same original shim pack really should get it done... as long as the gear set was original to the housing and was running good. (noise free)
AGAIN if you are reusing the carrier bearings and races and you can pull the carrier out with a good pull with out caps on it is TOO LOOSE... you need a shim pack or you will need NEW carrier bearings and races yours have some wear. The carrier can not be loose in the carrier saddles at all or the pinion will push it over and you will get odd pattern mesh and it WILL MAKE noise sooner or later.
Jim