Pinion Bearing Question and Shimming
#1
"Unregistered Gun"
Platinum Member
Thread Starter
Pinion Bearing Question and Shimming
So I have a 0F730808 Bravo 1 and I'm rebuilding with the newer/thicker floor gear set and supporting hardware to do this. With doing this upgrade I need this pinion bearing (31-8M0103472) that requires it to be shimmed. According to Service Manual 28 Supplement it says for drives 0W100000 and up to start with a 0.035 shim to start with to achieve a 0.025 clearance/backlash. With my older drive, would a 0.035 shim still be a good starting point??
With a older drive, would it be better to use the pinion bearing (31-8M0104358) that don't require shimming?
With a older drive, would it be better to use the pinion bearing (31-8M0104358) that don't require shimming?
#2
VIP Member
VIP Member
Do you have the pinion shimming tool?
If you don’t, you’re probably better off using the older style bearing that
doesn’t need shimmed
Once I got into my 1st upper with the new style shimmed bearing I bought the shimming
tool and after that I never used the old style bearings again.
.035 seems about right, but without the tool to verify, it’s just a guess
If you don’t, you’re probably better off using the older style bearing that
doesn’t need shimmed
Once I got into my 1st upper with the new style shimmed bearing I bought the shimming
tool and after that I never used the old style bearings again.
.035 seems about right, but without the tool to verify, it’s just a guess
Last edited by JaayTeee; 05-03-2021 at 11:02 PM.
#3
"Unregistered Gun"
Platinum Member
Thread Starter
Do you have the pinion shimming tool?
If you don’t, you’re probably better off using the older style bearing that
doesn’t need shimmed
Once I got into my 1st upper with the new style shimmed bearing I bought the shimming
tool and after that I never used the old style bearings again.
.035 seems about right, but without the tool to verify, it’s just a guess
If you don’t, you’re probably better off using the older style bearing that
doesn’t need shimmed
Once I got into my 1st upper with the new style shimmed bearing I bought the shimming
tool and after that I never used the old style bearings again.
.035 seems about right, but without the tool to verify, it’s just a guess
#4
Gold Member
Gold Member
Hey Jim, if you don't want to use the shim,,just use the old style race that doesn't need a shim ,,the bearings are the same,,just a different race as used in the older Bravo's, the Timken race part number for the old style is 28621.,,if you install the new style race that needs a shim it must be measured with the shimming tool,, no telling where the pinion gear depth will be until you measure it.
You also must then check the driven gear backlash on both gears with a stub shaft , dial indicator, clamping tool, and the correct flag on the stub shaft for the gear ratio.,, the Merc. manual gives you a cross reference for the driven gear shims compared to shims on the older housing, but that is not exact either,, you must check the backlash.to be sure it's in spec.
Hope this helps.
Mike
You also must then check the driven gear backlash on both gears with a stub shaft , dial indicator, clamping tool, and the correct flag on the stub shaft for the gear ratio.,, the Merc. manual gives you a cross reference for the driven gear shims compared to shims on the older housing, but that is not exact either,, you must check the backlash.to be sure it's in spec.
Hope this helps.
Mike
Last edited by 253; 05-05-2021 at 11:03 AM.