4.0 how much running gear can I use

[bronco jim]

Hi! Guys,
Newbe here this looks like a great forum here. I have a 87 bII thinking about droping in a 4.0 and the auto. tranny what else do I need to replace from the BII? I'am just doing some off roading in the mud and logging roads. Putting on 33/10.00 on a 8in. rim and looking at James Duff 3in. lift. What do you guys think? Any input will be welcome,

Thanks Jim

[bronco jim]

Sorry guys the tires are 31/10.50 15in. rims (old age )
Jim

[clem]

Don't forget to get the computer and wiring harness, rad and maybe the drive shafts. If you have a donor with the dana 35 and 8.8" running gear I'd hold on to it for future upgrades.

[Ruffinit]

You might see if you can get a C5 from a BII for the auto instead of the ODs that came with the 4.0s. They're overall a better tranny.