i only have 14k miles on my truck with a fabtech lift...its only been offroad once since the lift and it was really nothing (just incase it matters).. but anyways a few days this problem started happening and it seems pretty serious.

It starts out as this weird sound coming from the front end, then it clunks and everything is normal for a while.. The weird noise is kinda like a sizzling noise but not quite..

It does this a few times a day

 

bump..

 

Sounds like a vacuum leak for the front differential.

 

what could cause that, and is it serious?

 

It can be serious. What you need to check is see if you can engage 4x4 just and ensure that 4x4 is disengaging.

 

should i do that standing still or moving or does it matter?

 

i just cranked the truck and switched it to and from 4hi.. the light came on and i could hear like a clicking noise outside the truck so im assuming it engaged?

 

anyone?? i havent driven it since yesterday..ill take it to the dealership if i cant get this guy to take a look at it