8 3/4 differential swap issues...

[67DART340]

I have a 67 Dart 340, 4 speed with a transplanted 72 engine, 4 speed overdrive, and differential. The differential pumpkin is a 1820657, a C body diff (58-64) with 3.58:1 (yes, I said 3.58) gears, an open rear (non-sure grip). Wanting to put a sure grip, I bought a 489 pumpkin with 3.55:1 gears at E-Town last month. It was possibly rebuilt, and had reasonable tolerances. After it was installed the axles would not go in all the way, most likely the clutch splines not aligned in the 2 cone style clutches. This was fixed by locking the drive shaft and forcing the cones to slip by turning the axles until the splines lined up and the axles slid in all the way. But, now the axles bearings are not tight, even with the right side aduster maxed in, as if the bearing race is in farther than before. The bearings were fine before the changes were made. The the axle seals were changed, as were all the gaskets. Any suggestions. :sad5:

Thanks, Chaz.....

 

[demon seed]

If you're sure that the sure grip is a cone type and not a clutch pack type then it sounds like you're missing the thrust block. Remove both axles and shine a light from one end to the other, if it looks like an open hole then the block ain't there and you've got 2 options. You might also see a small pin going through but that's not the thrust block.

 

[fishy68]

If you're sure that the sure grip is a cone type and not a clutch pack type then it sounds like you're missing the thust block. Remove both axles and shine a light from one end to the other, if it looks like an open hole then the block ain't there and you've got 2 options.

Yep. That's what it sounds like to me too. A lot of guys pull the thrust block (used in the cone type) or thrust pins (used in the clutch type) because you have to if you want to run green axle bearings.

 

[67DART340]

Thanks for the input "demon seed" and "fishy68".... I'm pretty sure it's the cone type... I just rebuilt a clutch type about a year ago... I guess I can replace the trust block or thrust pin if it's missing or replace the axle bearings?... I have not pulled the axles out again since I was awaiting some answers... Thanks.. Charlie...