4wd issue....

[Archaic2021]

So recently bought back my old truck. Had a busted front differential. I mean the case was split. So I bought a used one of craigslist that was supose to have the same gear ratio.

 

I got the new diff in and when I engage 4wd the truck feels like it's in a bind. The truck will move but it's like it's in 4low. It'll actually go about 5 feet then it won't move at all unless I give it a little throttle. It also sounds like the rear tires dug into the gravel a little at the same time. When I put the truck back in 2wd no big noise but it feels like the truck is de-compressing..like when you coming out of 4wd on a steep hill or something.

 

I haven't owned the trucks in 7 years. I'm thinking they put a new rea-end in it with a higher or lower gear ratio. The service brake system is on so maybe that's a good indicator.

 

So either the guy I got the front diff from didn't know what he had (which his truck was highly modded..lifted, cammed and he seemed to know what he was talking about.

 

Or the rear has been replaced.

 

Or possible transfer case?

[Archaic2021]

So I pulled the cover off the rear...and it still has 3.42s

 

Before I go and pull this front transfer case back out to pull it apart and check the gears is there anything else that could cause this issue?