I have a 95 xj and experince a loud low pitched vibration at high speeds (about 40 to 50 mph) when in four wheel drive high. What could cause this?

 

What type of surface are you driving on? Pavement is bad...

 

Yeah bro you shouldnt be in 4x4 in pavement. It binds up the axle and everything.

 

...if u got NP231 t-case...then it is

 

I'm pretty sure it's bad for all transfer cases if you have a solid front axle...

Edit: okay I lied. its only the 231. which I have. Damn it.

 

According to my manual, given I have the np242, it says that I can use Full-Time 4 wheel drive up to around 55 mph. I have never tried using it that fast, but I have gone around 35 on pavement and it seemed to be fine.

 

my guess would be the double cardan joint on the front drive line T/case side.

But could be the T/case its self.

 

Says he has a 231...

 

Yea I have a 231, never had this problem before, but i live in an icey area so i try to keep it in four wheel when the weather is bad. Would it be worth it to pull the front drive shaft off and see if it still does it so I can narrow it down to either the front drive shaft or axle doin it?

 

that would be my first step. if it goes away 90% sure its in the shaft.

 

He never said what kind he has. That was me. This is my problem, my 4x4 Works pretty good, I dont think it was ever used. I do wish I kinda had manual hubs tho.

 

It says he has a np231 in his vehicle info.