My first thought was the wheel bearings until I started to do a little research, now I'm not sure. Anyway, it makes this grinding noise only when I make a sharp left turn going uphill. If I'm going downhill and make left turns, it doesn't do it, and making right turns going uphill doesn't either, only lefthand uphill turns make this noise. The only work that has been done to the front end is the left caliper was replaced in August because it was sticking, and back in March I had to have the same caliper (which only had about 10k miles on it) and the rotor replaced because the replacement caliper started sticking too. I also had all four shocks replaced in August at the same time as the caliper. I only noticed the noise after I had the caliper replaced the first time, and back then it was only occasional, it didn't do it on every lefthand uphill turn. Now it seems to be doing it on every turn like that, and I believe it has gotten worse since I had the most recent brake work done. Also, the faster I go around the turn the louder the noise gets. The truck is a 1992, four wheel drive with a 3.9L V6.

 

Crawl under the front wheel you think is making the noise. Dont jack the truck up, just crawl under so everything is in the same position as when you are driving. And also turn the wheel all the way to the left before you look under. See if there are any rub marks. There must be if its a grinding noise. Look at the inside of the wheel for any rub marks. Maybe the hard parts of the brake hose that attaches to the caliper didn't match up the same way as on the old caliper. See if that may be rubber. Im sure you will see something. Tell me how you make out.

 

i would jack up the wheel you think it is and wiggle the wheel side to side and top to bottom. if you get any play would indicate bearing or maybe when you had work done replacing the rotor the nut holding the hub on was not tightened enough.....

 

Well I crawled under it to look for any rubbbing and didn't see any, then I took it for a short drive to a place where it usually makes this noise and I didn't hear it today. The only change I made between my drive home yesterday and this morning was removing a ripped piece of the rubber shielding that's on the inside of the fender, it was catching and rubbing on the tie rod when the wheel was all the way to the left. If it was the wheel bearing, wouldn't it be making noise all the time?

 

you are correct, if it was the wheel bearing it would be whenever the truck is moving. And you'd probably feel some play in the wheel if you jacked it up and gave it a wiggle. Glad you solved it. Probably that rubber piece that covers the shock absorber right? If I were you I would do a zip tie repair. Not a rear critical component, just a splash gaurd if you drive through a puddle or mud keeps it off the headers.

 

Well that wasn't it, so tomorrow I'm digging the jack out of the garage and checking the wheel. After I got home today, I crawled under and checked around the bearing to see if it might be getting hot or anything, and the left bearing, which is the one I suspect is going bad, seemed to be cooler than the right bearing. I did notice that it looks like something might possibly be rubbing the rotor too, there were a few marks on there that I don't think should be on there.

 

I jacked it up and checked the wheel, there is no play at all, and I turned it the whole way to the left and spun it around and didn't hear anything rubbing, but it seems like I have to be going at least 25-30 mph to get it to make that noise, so obviously I couldn't get it spinning that fast by hand, but still I should've been able to see something.

 

Would a CV joint cause that noise? Since it only does it on sharp turns, that would be the only thing in the front end that I can think of that would be operating differently than it does when you travel straight.

 

cv joints will usually make a clicking noise when they are worn out its usually loudest when you accelerate out of a sharp turn. are any of your boots ripped or have you replaced any of them? if the front end is tight and the wheel bearing and drive axles are good I would pull both front wheels off and check that your calipers were installed properly and that sliders were lubed and are not sticking up causing drag

 

also check the dust shields behind the rotors