I'm trying to id a noise that is making me very nervous...



When in 4x4, switched from the dash and when locked as well there is a squeek that sounds like it is coming from the left front. I would explain it as a rotational noise. When in the cab it still sounds like a deep hum. Kill the 4x4 and the noise stops.



This summer I serviced the hubs; bearings through the abs sensor, needle bearings and serviced the lockouts. Ujoints on rear driveshafts and carrier bearing replaced, shaft balanced (shouldn't matter as it only happens in 4x4.



How can I isolate the source? I assume it must be axle or diff related. If I was to drop the main drive shaftand jack up the front end (on stands of course) would engauging the 4x4 be asking for problems?



Thanks,

Wink

 

I would start by jacking up the front end of the truck get both front tires off the groud put it in 4x4 and spin the front tire by hand and see if you can hear where it is coming from...

 

Thanks Nolan! I got it up on stands this am and was able to isolate it to the front driveshaft. After dropping the shaft it was in the CV joint. So off to see the folks at Rocky Mountain Driveline and it should be ready tomorrow. Not cheap but it will be good to know it won't come apart when 4wd is needed!

Wink

 

Thanks for the update glad you got it figured out.