I would say that it can hold up to pretty much stock power levels. Its just an Borg Warner 1354e. If you increase your power too much, then I would say you need to look into both a built trans and tougher transfer case. But I don't know of any cases that will bolt up to the ranger's tranny or any upgraded trans that will bolt up to the engine and work without a lot of modifications.
Also, a lot of guys swap in a manual 1354 just because the manual version is more reliable cuz there will be no electrical diagrams. I am also fairly confident that both the electric and manual internals are the same durability wise, but I could be wrong.
Also, a lot of guys swap in a manual 1354 just because the manual version is more reliable cuz there will be no electrical diagrams. I am also fairly confident that both the electric and manual internals are the same durability wise, but I could be wrong.