I took my truck out in the snow and used 4wd for a long period for probably the first time in its life. Since I usually unlock right after what ever required it.

After about 2 hours of banging around in ruts and such I was on my way home and noticed a loud metal grinding every time we hit a bump. I checked the suspension can't see any problems. Jacked up the front end spun the tires wiggled and jiggled locked/unlocked the hubs spun the drive shaft.

I really don't know how to find this I looked around for something loose can't find anything

I can't safely drive it like this =\

 

I don't know if this will be a huge help, but seeing how many replies you've gotten so far....well, some input is better than none.

Any chance your tires are catching the liners on the inside of the wheel wells? I get that sometimes at full turn, with my 37s catching those plastic pieces.

Also, maybe have a look at your leaf spring bushings? If you haven't replaced them in a long time, maybe all the snow bashing managed to push them past the breaking point? I had a pretty massive "clunk" every time I hit a bump (not really a grinding), but it turned out my bushings were gone.

 

Yeah, that's a tough one with such vague information.

Some clarification. Does this only happen when you're in 4WD? Hard to tell if that's what you meant in the post. Were you in vacuum-supplied ESOF hub lock or manually locked in when this was occurring?

Since you looked over the suspension, I'd start with the easy stuff, low hanging fruit as they say:

1. Lug nuts tight
2. brake caliper and caliper brackets tight and aligned properly
3. foreign objects in the braking system, damage to rotors
4. foreign objects in the steering knuckle, so between the ball joints and impacting the front shaft u-joints intermittently
5. play in the ball joints
6. play in the tie rod ends
7. play/damage in steering gearbox or pitman arm to drag link connection
8. remove and inspect autolock hubs for proper operation
9. play in front diff input shaft (up and down, side to side)
10. remove front diff cover and visually inspect diff components for mechanical damage.

 

Thank you for your responses. I decided to search the entire bottom of the truck for something that rattles and saw these seals that were broken.

I shook the front left axle and it moves all over the place. Would this be a hub issue? Spindle bearing?


This is exactly what mine is doing. This guy replaced everything though. I'm hoping to convert to manual hubs, since my jeep uses them too. (emergency spares)


Broken seals

 

Anyone know what I'll need to replace?

I live 20 miles away and would like to order pick up the parts before heading up.

 

There is some movement there normally,but I think thats a little loose. Be sure to check the hub lockers(do you still have the stock autos or maybe Warn),they actually support the outer axle so if they get worn or the break you will have more movement.It does seem a little too much though..if its only the one side,try using the hub locker from the other side and see if it still does it.

 

Oh those. Yeah, I went through that a while back, those are just dust covers. They more or less prevent dirt and rocks from getting into the axle tube. The seal that keeps diff oil from coming out right there is located back at the differential. In other words, it's a dry axle tube. Those seals aren't the culprit causing your front end noise.

I haven't had to replace the ones on the wheel side though, that's new to me. The axle half shafts are only supported at the diff and at the interior of the hubs, so some play is normal.

Have you tried greasing the front wheel bearings by pumping through the ABS sensors? The wheel side seal would prevent grime from getting to those so perhaps they are getting washed out.

There are also needle bearings on the interior where the half shaft goes through the hub that can be greased. These needle bearings would be spinning when the hubs are unlocked and you're in 4x2 rolling down the road.

If it's the main bearings in the hubs causing your noise and greasing through the ABS sensor hole doesn't help, my understanding is that those are a sealed unit and require simultaneous replacement of everything bolting to the steering knuckle. That's info from my neighbor though; I haven't torn into it myself, just removed them for various reasons (see "dust covers" above...)

Hopefully someone more knowledgeable can chime in with some different ideas.