How to Remove an Overdrive

How to remove an Overdrive from a Dana 18 transfer case:
1. Remove the five  3 ½” mounting bolts that attach the aluminum housing of the rear assembly to the transfer case only.
2. You should be able to get that aluminum housing to come back a little, so that you can put a screw driver in between the aluminum housing and the transfer case.
3. Be careful not to damage the aluminum housing when you use two screwdrivers, one on each side to pry the casting to the rear.
4. What is happening is that there is a cage bearing inside of a part called a spyder blank, and this spyder blank shrinks and conforms to the shape of the cage bearing housing making it a tight fit.
5. You have to pry evenly because if  you don’t you only make it tighter to remove. When you have it back far enough that your screwdriver is too small, then add a piece of wood for a shim and continue until it is removed. This is the only way to remove the rear assembly without causing possible damage to other parts.
6. Do not remove any other bolts or parts as they do you no good except to give you a bag full of parts that you my lose.
7. Next remove the internal snap ring inside the barrel assembly inside the t/f case by compressing it.
8. The next part is the tab washer. Now this part serves the purpose of a lock washer as it locks the drive nut from turning (unscrewing) when the OD is installed. It may be tight, if so carefully use a 3/8” extension and wiggle it inside the tab washer and that
should allow you to remove it.
9. Once the tab washer is removed, take a ½” extension and unscrew the drive nut inside the barrel gear to remove this from the transfer case. The drive nut will not come out as it is a part of the barrel assembly.
10. If you have an extremely difficult removal and need some help, don’t hesitate to give me an e-mail or a call and I will try to help you with it.
11. Do not use a torch!!!!  Do not remove any other bolts other than the 5  3½” bolts to remove!!!!! Worse case senerio, remove the assembly as shown in this picture (Coming soon) and send it to me so you don’t damage it.