Recently I've noticed a grinding noise coming from my front end. It especially happens when slowing to a stop and slowly rolling forward from a stop. It only happens when I have my hubs locked in. Any ideas?

Thanks,
Chris

 

Well, check your brakes first. Thats always a good place to start. Pads that are gone will make some really neat grinding noises!

Next up, if not brakes, jack the front end up, and spin the tires by hand after leaving the truck in neutral. It could be a bearing lacking some grease and on its way out the door, or something else. But once you test this, it will narrow down what it could be!

 

Maybe check fluid in front diff to see if you have any metal wear in the front diff? Also it might be axleshaft ujoints or the small needle bearings in the spindles that hold the axleshafts up and prevent them from rubbing on the spindles. I would look at this since you said it only occurs when hubs are locked in.

the bearing for the axle shaft i am talking about is called the spindle needle bearing in the above picture

 

i recently replaced my spindle needle bearing, but mine had no needles and i needed a new outer shaft. but its not to bad and the bearing and seal should be around 20 bucks. im assuming what ever it is you will have to take the hub apart and spindle off any how. a spindle puller really comes in handy.

 

definitely use a spindle puller and not a chisel! You can get that bearing and seal in a kit now from all the parts stores.

 

First off thanks for all the help guys!

First thing I'm going to do is empty and refill both the front and rear diff because I feel like that should be done anyway. Any recommendations on a fluid? I've always heard good things about Royal Purple, is that a good route?

Second I will check my spindle needle bearings and seals out. Is this a hard task? Should I also go ahead and replace my inner wheel bearing while I'm in there? Truck has 135K miles on it and I'm pretty sure they've never been done.

Thanks again for all the help,
Chris

 

here is how I changed my rotors.... take what you need https://www.ford-trucks.com/forums/8...ors-today.html

 

I personally wouldn't pay the high price for Royal Purple, I am not saying it bad. I would just go down to oriely's, or local parts store, and have them pull up your model of truck and find the oil weight the axles require and buy the middle of the price gear oil, not the cheapest nor the most expensive. It's not like you have high tolerance parts in your axles like you do in your tranny and engine. The gears and bearing just need an oil bath. Also check to see if you have a limited slip diff in the rear, more than likely yes, if so you will need to get the oil additive for limited slip diff. that cost around $5-8 for a tube and if you don't get it then you will trash your limited slip diff.

To fully check the spindle bearings you will need to remove your hubs to remove the spindle, the bearings is pressed into the back of the spindle.Your question on wheel bearings. If it were me doing the job I would buy two set of spindle bearing kits, two inner and outer wheel bearings, two seals, and 2-3 container of wheel bearing grease before I would pull the front axle apart, to minimize the amount of trips to parts store. Granted you might not need all this but it will come in handy if you do and whatever you don't need you can take back at a later time (IE the next time you need parts for your truck). I also wouldn't replace the bearings unless they were shot. You need to clean them up real well and inspect them for pitting and how easy each roller spins in the bearing cage, if they meet your inspection then repack and reinstall if not just go to your goody bag from the parts store and replace.

Also I have never used a spindle puller in my life. I have always used a dead blow hammer and hit between the two spots where the inner and outer wheel bearings ride and all the way around the spindle to create a rocking motion of the spindle to get it out of the knuckle. The dead blow hammer won't mar the spindle and makes easy work of seized on spindles. Don't use a steel hammer and don't even think about hitting on the area the bearings ride on or the wheel nut threads. If you can't tell where the bearing rides just take your inner bearing and install onto spindle and then put outer bearing on and push them towards the center of axle. The spot where they stop is where they ride.

 

Redline, Amsoil or Shaeffers 75-w140 synthetic in both pumpkins. I run the Redline. The cost is negligible considering the service interval and the benefit far outweighs the cost difference.

 

What are your service intervals and what are the benefits your seeing in your axles??

 

30k or so or every three years for the differentials. Check the levels once a year. Same time as my yearly check of the undercarriage. The front axles themselves aren't in the equation. Only the rears (bearings) would benefit. Running good synthetics in the drivetrain has many advantages. Durability is increased due to lower temps and improved lubrication along with better fuel mileage. Peace of mind is also an important factor. To me anyway.

As to the OP's issue of a locked up u joint either in the front axle, front driveshaft or possibly a hub problem obviously the gear oil would have no effect. Unless there was none present or a very low level in the differential.

 

I was talking about checking gear oil to see if it had contaimentation like metal shavings, etc. which would lead me to believe it had a bad bearing or ring and pinion failure, which could cause a grinding noise in the front end only if the hubs were locked or if you had the truck in four wheel drive. I wasn't concerned with oil level because you would more than likely notice the puddle under the truck or oil leaking out of the axle tubes onto the front tires.

Also you are not going to notice a difference in heat dissipation between regular oil and your redline oil because the steel in the axle is going to dissipate the heat at the same rate, unless you had one of those nice high capacity aluminum diff covers. I am not lumping engines and transmission into the previous statement either. The steel in the axle will be the limiting factor, and can you honestly tell me running redline in just your axles will give you a noticeable difference in millage. I don't buy these statements from the manufacture and don't think this extra money is worth it for axle lube. I do believe putting the extra money into oil for the engine and tranny is important though.

 

How much damage am I doing driving around with this grinding if it is the spindle bearings? Also it's just the passenger side that is making the noise if that helps.

 

driving around on it could tear up your outer shaft, unlock your hubs if your going to drive on it

 

Your wrong about the synthetic. Your mechanical and parts suggestions are spot on. Lets agree to disagree and try to help out the OP.