I had the same problem. I'm sure this is a problem with everyone. I had to call Cen. They told me to heat up the screws with heat. I used a small touch directly on the screw head. A torch lighter would probably work better. This worked for me even after almost stripping the screws and breaking 3 allen wrenches. Make sure to hold the diff with pliers for the whole assembly will get very hot. Cen told me to follow the directions for the reverse install. Nowhere did it have these instructions. Crappy direction, good CEN support on phone thank goodness for free long distance calling.

I tried to loosen the diff screws with three torch lighters (two of which where tripple flame torches) multiple times. I eventually gave up becuase I wanted to drive the truck and was tired of messing around witht the diffs.

I just put new diff fluid in mine last week. All three. Stuck mine in the vise with some jaw protectors, and used the heat gun on the side for about 30 sec., they all come loose easily after that. Loctite doesn't hold up to well to severe heat.

Also, please make sure to use HIGH QUALITY allen wrenches. Our factory team drivers are saying "they need to use MIP/THORP style wrenches on that part."

Also we sell super high quality wrenches from CEN as well.

To get the screws out you will need to heat them up like Ing has stated. The factory uses red loctite due to the nature of this truck's vibration and heavy demenor.