8 3/4 ring and pinion swapout

[Illahe]

That's the "ballpark" figure you shoot for regarding pinion gear depth. It's ballpark, because you don't go by that number, you go by the gear pattern. That number is just to get you close.

@mopower440

My understanding is that the number comes from when the gear set was machined.

I use a magnet (from any decent hardware store) because of the pinion offset and then I place a parallelly ground ruler in the bearing saddles. Take a caliper and get a depth measurement (minus the ruler, and plus the magnet thickness) to get within a few thousands. Then add 1/2 of the bearing race diameter and you have a measurement of the pinion depth to centerline of the ring gear.

Assemble and see what the pattern is telling you. Its all trial an error on the pattern.

How bout you Rusty?

 

[RustyRatRod]

@mopower440

My understanding is that the number comes from when the gear set was machined.

I use a magnet (from any decent hardware store) because of the pinion offset and then I place a parallelly ground ruler in the bearing saddles. Take a caliper and get a depth measurement (minus the ruler, and plus the magnet thickness) to get within a few thousands. Then add 1/2 of the bearing race diameter and you have a measurement of the pinion depth to centerline of the ring gear.

Assemble and see what the pattern is telling you. Its all trial an error on the pattern.

How bout you Rusty?

I've always done it just like I described. I get close to or right on the number engraved on the end of the pinion, then I check the pattern. A few times, It's been good so I let it ride. Sometimes though it's not, so I add or subtract pinion shims as needed. It's too bad Chrysler didn't catch on and copy the Ford 9". Their pinion shims do not require pressing the pinion bearing on and off.