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Ring & Pinion Guru's

What do you guys think about this pattern?

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gear2.jpeg - 29240 Bytes

This is a Richmon 3.55 with the pinion installed about .001" shy of the marked pinion depth. I tried moving up & down ~.005" in an attempt to move the patterns closer to the tooth flank but the pattern gets worse. Actually the coast pattern doesn't change much but the drive pattern moves to either side and doesn't look good.

I already had this rear in the car with a similar pattern. I had a slight howl and took it out to find that the backlash opened from .008" to .015". I guess I didn't seat the adjuster correctly.

I tried fooling with the depth again since I had the darn thing out and can't seem to get the pattern any better than this.

I'm hoping that by making sure the adjuster is seated good and the .008" backlash is maintained that my howl will go away.

They seem fine on test drive but a slight whine from 10mph to stop. Put it in neutral and its gone.

Regular driving and cruising they are quiet.

Is some gear noise acceptable?


Most aftermarket gear sets tend to be noisy......let them "break in" for a few hundred miles they will quiet up

Or just hammer down and listen to another kind of music!

If you have trouble getting a consistent BL reading, the posi unit may be warped. Also, when setting BL, move the ring gear into the pinion until you have .001" of BL in the tightest spot. Lock the adjuster and tighten the cap on the pinion side of the ring gear. Then move the other adjuster until you get the proper BL reading. You will actually be pre-loading the ring gear bearings. This should keep the BL reading where you set it at.

Your setup looks great, the noise they are making is because they are Richmond, I won't say anymore.


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