Wear pattern rear setup

[jtm311]

Hey guys what would you say about this wear pattern. I have my backlash set to 6. Not sure if this is telling me the pinion is still to deep?

Thanks,
john

[big gear head]

The pinion is too deep. Take about .003 to .005 out of the pinion shim and try again. Post pictures again.

[JEFFTATE]

Yes , the pinion is too deep ..

[jtm311]

ok here is my problem I have a .006 shim under the pinion now, I also pull the shim out and try again looks the same. The old pinion had no shims at all? I checked the race and it is fully seated. now what?

[big gear head]

There should be at least .025 shim under the pinion bearing. These rear ends usually have between .025 and .045 pinion shim and usually around .030 to .037 is normal. If you only have .006 then something is wrong. Did you install the bearing race yourself? Are there any shims under the bearing race? Did you check the numbers on the bearing and race when you installed them? Did you use a .001 feeler gauge to see if they are both fully seated?

[jtm311]

Thanks for the reply, yes I installed the race. However, I first made a set of setup bearing out of new bearings same which came in the rebuild kit. Same thing so I know the race went all the way down, even when I installed the new bearing and race I checked it with feeler gauge it was fully seated. What I find funny is why does the old pinion also have no shims? I'm at a loss two days and can not find anything. Also the backlash is at 6

How bad do you think it will whine if I left it?

John

[big gear head]

I wouldn't be worried about the noise. I would be worried about the gears wearing out or breaking. Your housing must have been machined wrong when it was made. I would find a way to install a .001 to .003 shim and try the pattern again with about .007 to .009 backlash.

[jtm311]

I was thinking what if I was to just increase the backlash say to 9 would that not move the pattern to the middle?

[big gear head]

No, you need to move the pinion out.

[jtm311]

I had an idea last night, I may take the race out and bring it to a friends shop and surface grind the base by .010 this would allow the pinion to drop by .010. I may be able to go further but have to see how much meat is on the race.

[jtm311]

Ok I was able to take .010 of the base of the bearing race. I'm now using a .011 shim and backlash at .005

much better?
John

[big gear head]

That's much better, but why are you keeping the backlash so tight? It needs to be at least .007 unless you are usnig 2 step gears. The pinion is still a little too deep, but open up the backlash a little first and see what happens to the pattern.

[jtm311]

I was not try to keep it tight I had to get more shims so I did now she is set to .008 backlash better?

[big gear head]

Yes, that is better. You are very close. You can stop here or make it a little better by taking about.002 out of the pinion shim.

[jtm311]

Thanks for all the help I did drop to the .010 shim I would not say it made a big change but I will keep it that way. Thanks again. Now to weld on the suspension brackets

John

[John Wright]

I like that yellow vs the blue that I used for checking the accel/decel pattern. It makes the pattern very visible.

[big gear head]

[CamaroAJ]

when you were checking the pattern did you load the ring gear? like putting a pry bar between the housing and ring gear then turned the pinion?

the second pattern you posted looks pretty good, i would run with it.

[jtm311]

Hello AJ No I did not, however, I applied pressure with my hand to act like a load

Thanks just waiting on my Dial torque wrench so I can set the bearing pre-load.

[CamaroAJ]

before you button everything up you might want to double triple check that just to be 100%. you should be good to go.

dial torque wrencehs are nice. i have used mine many many times but oddly enough it has only been on front and rear axle pinion bearing preload lol.