MOTOBILT MB3020 Jeep LJ Back Half Kit Instructions

June 3, 2024
MOTOBILT

MOTOBILT logo MB3020 Jeep LJ Back Half Kit
Instructions Manual

MOTOBILT MB3020 Jeep LJ Back Half Kit

MB3020 Jeep LJ Back Half Kit

This back half kit allows you to replace the rear section of the stock frame completely to make room for coil overs and to move the rear axle further back. Remove all factory suspension components, fuel tank, rear axle, and other parts from the rear frame section.
The first step is to cut the frame where the upward curve begins.

MOTOBILT MB3020 Jeep LJ Back Half Kit - Figure 1

This will allow us to slide on the first part of the Motobilt Jeep LJ back half kit. The new frame rail sections come welded and ready to slide over the frame rails.

MOTOBILT MB3020 Jeep LJ Back Half Kit - Figure 2

The next step was to mock up the long straight-frame rail sections and rear bumper.

On the inside of the long straight frame rails, there is a body mount tab with a hole. This lines up with the factory body mount in the middle of the cross member.

MOTOBILT MB3020 Jeep LJ Back Half Kit - Figure 4

This LJ has a 1.5″ body lift so we only had to cut the tub a small amount. You can see where we notched the body just below the tailgate. This kit will work without a body lift but you will need to cut more in this area.

MOTOBILT MB3020 Jeep LJ Back Half Kit - Figure 5

You can clearly see how the frame has moved further up and no longer dips down in the back. This means when we move the rear axle back we will have the necessary room while allowing us to keep the Jeep’s height as low as possible.
Once the body mount is bolted in you can square up the frame with the bumper and make sure you are happy with the placement. Tack welded all of the sections together. You can now weld the back half kit while it’s underneath the Jeep or you can choose to remove it and weld it separately.

MOTOBILT MB3020 Jeep LJ Back Half Kit - Figure 6

Be sure to test fit the frame rails during the process to ensure nothing moves. Remember it’s better to check and be sure than to rush things. You will need to weld the reinforcement end caps that connect the frame rails to the bumper.

MOTOBILT MB3020 Jeep LJ Back Half Kit - Figure 7

Next, reinstall the back half of the Jeep and weld the new frame rails to the factory rails.

MOTOBILT logo

Read User Manual Online (PDF format)

Read User Manual Online (PDF format)  >>

Download This Manual (PDF format)

Download this manual  >>

Related Manuals