Aloha Folks,
So I read up all over regarding the humming sound from the front area of our vehicles.
I believe its either the front diff or the prop shaft.
The humming sound is very simillar to that of "aggressive tread tires" and only comes when you accelerate. Its specific to only when accelerating. I can be rolling down hill or going uphill and no sound till you accelerate. My 06 has had the "pop" when you release pedal and hit the accelerator and the sound seems to come even before the pop. (makes me more suspicious its the axel).
Hoping it is the prop shaft cause that is much more affordable.
Just wanted to pick your brains about what it might be? 117K miles now and the motor is still strong, always changed fluids before the recomended time. Infact this sound seem to become apparent after changing the diff fluids. Also at the same time I got new AT tires vs. the mud tires i had before so the sound is now more noticeable. Been driving this way for a month now and the sound seems to be increasing slightly.
Funny thing is about a week ago I put it in 4L driving home on my dirt road. The next morning the sound was gone till I hit the highway for several miles and it came back.
Any ideas or questions I can answer to better figure this out before I take it to the gear/transmission shop.
Thanks always for the support.

 

Yep. Are your hubs in good shape?
The cage (nearest transfer) on the front drive shaft has a centering assembly is it possible it is failing?
What weight gear lube? Brand?
Chris

 

Hubs both have very slight play when shaking the wheel (yep those are on the replacement list) but ive had thise fail several times on my Dodge Cummins before i stalling Yukon lock out hubs. Seems they never did produce a noise as much as it does affect steering on bumpy roads. I still have the poly bushings, washers and what nots to do the cross member bushing mod. Do you think it could be that? Would be awesome if thats all it was.
Regarding the diff oil i ised the recomended weight and baught valvoline synthetic.