I am trying to find a grinding noise that has developed in my truck. I cannot feel it in either of the shifters.

It originally started as a binding or clunking noise that would happen when I was turning either to the right or to the left and the only way I could get it to stop was to stop the vehicle. While chasing that problem I noticed that all the tierod ends were shot so I replaced all of those.

Upon further investigation I noticed that the front axle was locked in all the time, so I got to playing around with the front axle was locked in all the time. So I went to the CAD unit and found out that the shaft on the vacuum actuator was physically bent, so I went to the dealer and got a new vacuum actuator and replaced that. That fixed the axle being locked all the time.

Now when I am driving down the road I get a grinding noise that sounds exactly like when a synchro grinds on a manual transmission, only I am thinking that it is coming from the front axle. I am not sure if it is relevant but if I shift it into 4 wheel drive it makes the clunking noise again, I think the two are related.

I do not have very much experience with the CAD system on these trucks and was wondering if any of the Gurus had any suggestion on what it could be and how I can fix it?

Thanks,

 

Hub bearings?

 

jack the front up, check for play in the hubs like the previous post states.



check front diff fluid level/change.

check transfer case fluid level.

make sure 4wd shift linkage has full travel.

check the driveline.

 

Both wheel bearings are under a year old. Both have no play. I'll double check the fluid levels in both the differential and t-case.

U-joints on driveline are good. 4wd locks in so i'd assume the shift linkage has full travel.

This just started doing this one day, its not like its been doing it for awhile. It started with the clunking because the front axle was always locked into place, now that I've fixed that little problem the grinding noise appears.

 

does it clunk in 4x4 still mine clunks like crazy in 4x4 and every thing looks good in the cad and diff.

 

Yes it clunks in 4wd, i pulled the pass side axle shafts out and inspected the bearing in the axle tube. It looked good. I did notice though that the 4 bolts that hold the wheel bearing assembly to the steering knuckle were loose, so I am wondering if this wouldn't cause it. I have it all put back together, letting the RTV seal up tonight and going to take it for a spin in the morning to see if it fixed it.

If it didn't fix it then I guess i'll drop the transfer case and see if everything is fine in there because i've pretty much eliminated the front axle.

 

let me know if that fixed your problem.. i have a similar thing going. and would like to have a little more info going in..

goodluck. and thanks in advanced

 

Sorry it took me so long to reply I got sidetracked. Fixing the bolts on the hub did not fix my problem, although it did give me piece of mind now.

I expanded my research on the boards and actually found a common problem of the tailshaft snapring on the transfercase breaking, and how I understand it it lets the tailshaft move into the transfer case and grind against things as it is spinning.

I ripped the outside housing off of the transfercase (which can be done while it is still in the truck) and sure enough, there was pieces of snap ring inside of the tailshaft housing. I have ordered a snap ring and will be able to install it tomorrow and will update if that fixes my problem or not.