8 3/4 489 Case Suregrip 3:23 Gear Pattern

[Derron Cyrus]

Hi all. I'm new to the forum and am looking for advice on my gear pattern. I have just switched my 489 Cased Suregrip from 3:91 to 3:23 using a Solid Pinion Spacer, and I have set my pinion depth with shims below the inner bearing. I'm using a set of test bearings. Here are some pictures of my current gear pattern.

 

[68-500]

Coast side looks pretty good, but drive side could be a little deeper IMO. Not sure how to get there a little less backlash?

 

[khryslerkid]

I'd like to see a pic, coast and drive side, where the paste isn't so thick. You're close.

 

[Derron Cyrus]

I'd like to see a pic, coast and drive side, where the paste isn't so thick. You're close.

Here you go;
Thanks!!

 

[khryslerkid]

Here you go;
Thanks!!

View attachment 1289485 View attachment 1289486

View attachment 1289483 View attachment 1289484

I think it's deep enough. See what the consensus says. What backlash did you end up with?

 

[Derron Cyrus]

I think it's deep enough. See what the consensus says. What backlash did you end up with?

.009 using the old bearings.

 

[khryslerkid]

If the pinion and carrier bearings are preloaded to specs you should be good to switch to the new bearings. Using the new pinion bearings and races might not show as deep of a pattern. You're using the crush sleeve eliminator so it's easier to add a shim if you have too.

 

[steve340]

That pattern looks good - but see if it changes when you go to final setup.

 

[Derron Cyrus]

If the pinion and carrier bearings are preloaded to specs you should be good to switch to the new bearings. Using the new pinion bearings and races might not show as deep of a pattern. You're using the crush sleeve eliminator so it's easier to add a shim if you have too.

If the pinion and carrier bearings are preloaded to specs you should be good to switch to the new bearings. Using the new pinion bearings and races might not show as deep of a pattern. You're using the crush sleeve eliminator so it's easier to add a shim if you have too.

I'm using the old carrier bearings and races and new pinion inner and outer bearings. My struggle is setting the carrier-bearing preload. Are there any other tricks to set carrier bearing preload without a large micrometer to measure case stretch?

 

[steve340]

The factory service manual tells you to set to zero backlash and then tighten the correct spanner until you get 0.008"
This will preload the new side bearings.
Pretty sure I have given you correct info but easy to check for yourself.
The FSM are available free on the internet.

 

[wagonman]

New or used gears?

 

[66Satellite47]

Although my experience is pretty old, I'd say you are about as close as you may get.

 

[khryslerkid]

I'm using the old carrier bearings and races and new pinion inner and outer bearings. My struggle is setting the carrier-bearing preload. Are there any other tricks to set carrier bearing preload without a large micrometer to measure case stretch?

I've been told, "as tight as you can get them with a 18" spanner wrench". Well are you Popeye or Wimpy? I like steve340s response.

 

[RemCharger]

I built a tool to lay the torque to them

 

[68-500]

Ya after seeing it in second pics looks good

 

[khryslerkid]

Always rotate the bearings while applying the preload. Very important. A good coating of gear lube also.

 

[dvw]

Run it.
Doug

 

[Derron Cyrus]

Hi all, and thanks for your input.

I just got everything set up with the proper pinion bearings and followed the manual on the carrier bearing preload procedure. Here are some pictures with the preload set to .007

 

[steve340]

That looks pretty good.

 

[66Satellite47]

Better than I was ever to do on an 8 3/4.