Putting a new carrier and gears in my dana. I'm trying to figure out how much CARRIER preload I need and there is very little info out there on it. I spread my case with the spreader .015, and simply could not get the new carrier in there with shim stacks from old carrier. (I made setup bearings as well) So, is it acceptable to make it a snug fit with the case spread .015 and when the spreader is removed will that provide enough? Thanks...

More than enough. I usually put the shims in and start the carrier with bearings and rubber mallet it home. That's way less than .015.

I never use a spreader. Fit it and set backlash with a mild tap in. Then add .005" to each side.
Doug

Exactly what I do also.

Thanks guys!

I remember my first Dana. She was a wonderful girl and probably should have been a keeper.
The second Dana was an absolute train wreck and a crazy woman.
Oh, you guys were referring to rear ends..... I have several of those also and like mentioned above, never needed a spreader.