TunedPort350

Installing new gears, is this good enough or should I move the pinion ???

I set the pinion depth and backlash to Richmond specs, -0.001 for pinion depth (pinion etched 2.316 actual is 2.315) and +0.002 on the backlash (ring gear etched 0.010 actual is 0.012)

//<86TA>\\

iTrader: (15)

no thats improper, the pattersn want to be more centered, your pinion is too deep

big gear head

Actually the pinion is not deep enough. You need to add more pinion shim. I would try about .005 to .007 to start with and see how that goes.

TunedPort350

Thanks guys, I think when 86TA said "too deep" he meant "too deep into the housing", not too deep into the mesh... but I could be wrong. Either way I will try adding some pinion shims and see what happens.

Is there some type of constant or ratio between pinion depth and backlash... by that I mean if I place the pinion 0.007 deeper into the mesh I should also end up decreasing backlash (if I keep the carrier shims the same). I just figured that there must be some kind of ratio (like 0.003 pinion depth changes backlash 0.001 or something like that)

Thanks again for your help

big gear head

Each rear end is different. There might be a ratio for the 7.5, but I don't try to keep up with that. I just reset it each time I change the pinion depth.

TunedPort350

I went through multiple combinations... this seems to be the best I got...



Is this good ???

big gear head

That is much better. I would like to see the others that you had so I could tell how the pattern moved with different shims, but you shoudl be able to run that without any problems. You might try adjusting the backlash slightly in both directions to see if the coast side pattern spreads out a little more. Don't go outside of the recommended specs for the backlash.

TunedPort350

I have 7 pictures from different combinations I tried;

Left Carrier Shim = 0.226
Right Carrier Shim = 0.237
Pinion Shim = 0.035
Backlash = 0.0085



Left Carrier Shim = 0.226
Right Carrier Shim = 0.237
Pinion Shim = 0.032
Backlash = 0.010



Left Carrier Shim = 0.232
Right Carrier Shim = 0.240
Pinion Shim = 0.024
Backlash = 0.008



Left Carrier Shim = 0.232
Right Carrier Shim = 0.240
Pinion Shim = 0.024
Backlash = 0.012



Left Carrier Shim = 0.237
Right Carrier Shim = 0.226
Pinion Shim = 0.032
Backlash = 0.003



Left Carrier Shim = 0.237
Right Carrier Shim = 0.226
Pinion Shim = 0.029
Backlash = 0.005



Left Carrier Shim = 0.237
Right Carrier Shim = 0.226
Pinion Shim = 0.024
Backlash = 0.0075

big gear head

What pinion shim do you have in it right now?

TunedPort350

0.035 Pinion Shim, I ended up with just over 0.010 to just under 0.011 backlash (measuring different spots around the ring gear) with 0.005 preload on each side of the carrier. The mark on the ring gear called for 0.010.

I buttoned it all up, using crush sleeve on pinion with 25 in/lb and all new bearings etc... Then I put the axles in and set the E-brake for a little drag and this is what the final pattern looked like... I think I'm going to put fluid in and start the break in, what do you think?

big gear head

I think it will be fine. The drive pattern looks pretty good. The coast pattern isn't quite as good, but probably good enough. I think the .035 pinion shim was the correct choice.