Can you put a LSD carrier from a superduty into our trucks? My present axle is a 4.10 open carrier dually axle. I'd like to switch to a LSD, and I've found someone selling a 3 pinion unit.

Will it fit?

Is it a simple matter of using my present shims, or will I have to set the gears up again if I change carriers?

 

I have a SD 3 pinion LSD in my SRW 10.25. Not sure about a dually axle.
I made the swap when I went from 3.55's to 4.10's. I was able to just use the same shims but be ready to do the full set-up just in case.

 

Thanks Craig. How will I know if I need to fiddle with the shims?

It appears I needed to do it already. I was hooking up to my horse trailer and the left rear pair went off the gravel a little bit. I couldn't pull out and had to back and fill several times to get out.

 

Yep, open differentials suck off pavement! Sadly, the Ford limited slip are not a whole lot better.
Once you have the new gears on & the rear end reassembled, use the marking compound to check the contact between the gears. If you don't have good contact, you need to adjust the shims and/or pinion depth.

This covers the basics:


http://www.drivetrain.com/parts_cata...tructions.html

 

^^What he said. You should also watch some YouTube videos on how to set backlash using a dial caliper. You can get a dial caliper and magnetic base pretty cheap at Harbor Freight.