my68barracuda
Well-Known Member
Hello, changing out a ring and pinion set in a 742 8.75. I believe the ring and pinion being removed is an OE set. Has Mopar part number and a manufacturing date of 1968 stamped in it. I recently went through this differential and put all new bearings in it. I plan to reuse the bearing with the new gear set.
To my question, I know the large bearing at the pinion shaft gear end is a press fit. I have a new large bearing that I honed out the ID on to make it a hand fit and use that to get the shim thickness right. Then I heat the non modified large hearing in a toaster oven to 450 F or so and it fits on easily.
In assembling the new pinion I found that additional hone work was needed to get my set up bearing to fit on the new pinion. Previously that same set up bearing was a had fit to the OE pinion.
I then tried to fit the small pinion bearing on the new pinion. It would have been a real hard press.
I measured the small bearing pinion lands on the new pinion and the OE pinion.
New 1.3135
OE 1.3125
the new pinion shaft has a small bearing land .001 larger in diameter than the OE pinion shaft. I did not measure the large bearing pinion lands, but I bet the same condition exists there also.
questions:
1) am I correct in thinking that the small pinion bearing should be a good hand fit to the pinion shaft
2) To move forward with the assembly process I ground then honed the ID of the small bearing to make it a good hand fit. Is that OK or should I be worried over other feature on this gear set. I assembled the new ring gear to the hub and it went on 100% fine.
To my question, I know the large bearing at the pinion shaft gear end is a press fit. I have a new large bearing that I honed out the ID on to make it a hand fit and use that to get the shim thickness right. Then I heat the non modified large hearing in a toaster oven to 450 F or so and it fits on easily.
In assembling the new pinion I found that additional hone work was needed to get my set up bearing to fit on the new pinion. Previously that same set up bearing was a had fit to the OE pinion.
I then tried to fit the small pinion bearing on the new pinion. It would have been a real hard press.
I measured the small bearing pinion lands on the new pinion and the OE pinion.
New 1.3135
OE 1.3125
the new pinion shaft has a small bearing land .001 larger in diameter than the OE pinion shaft. I did not measure the large bearing pinion lands, but I bet the same condition exists there also.
questions:
1) am I correct in thinking that the small pinion bearing should be a good hand fit to the pinion shaft
2) To move forward with the assembly process I ground then honed the ID of the small bearing to make it a good hand fit. Is that OK or should I be worried over other feature on this gear set. I assembled the new ring gear to the hub and it went on 100% fine.
