i have a 1998 5.9l 4x4 , when i was tring out my 4 wheel drive i put it in 4 high and step on it there is a grinding noise it sounds like its comeing from the back??? no lights come on to indicate im in 4wheel drive, but i can feel it is. it does not seem 2 do it in reverse. any suggestions please help me.
my truck is a 1998 ram 4x4 1500 slt larime with a gas guzzleing 360

 

u-joints maybe. but ive heard numerous problems on rams where the front and/or rear diff. was replaced...so maybe one of your diffs is gone

 

If it does not do it when in 2wd and you think it's coming from the back, then I'd say the transfer case might be bad or the dbl. cardan joint on the front drive shaft. But you do need to check the front axle ujoints. Also the vacuum should be checked at the 2 hoses going into the CAD (right rear of front axle). But, all that is in the front. So make sure the noise is coming from where you think it is.

 

I've been battling the same issue for a while now.
Now I know its the transfer case.
I have not taken mine out yet, but I'm sure its in the guts of the NP231D
They are relatively simple, so if you take yours out, you should be to do overhaul one yourself.
I had several of these cases apart and its just a matter of aligning everything.
Hope this helps.

 

As long as you both have eliminated all other possibilities.

 

really? is there a DIY? or do you have/making up one?

 

now i cant get it 2 make the grinding sound but im on pavement. when it was grinding i was in 4 hi on dirt. my tires spinning

 

is it possible that somehow a rock got into the axle tube and caused the grinding?

 

is it posssible that it was not all the way engaged??? im not sure because i tryed it like 4 times. and when i stand on it it grindes and the tires spin. no light comes on saying im in 4x4 but i can feel it o n the pavement. do i have to be in neutral or park, or can i shift in gear????

 

theyare made to shift on the fly. but i always stop. put it in neutral, then shift it to 4wd. try it. and pull up hard on the shifter. it is possible its not fully engaged