Front end grinding noise

[GrinMedic]

I've been having a rhythmic low grinding noise that seems to be coming from the front end.
It increases in sound and frequency as speed increases,with little to no sound at speeds less than 10-15km/h
It is much more noticeable when coasting down a hill and seems to increase while turning right.

CV boots are not torn, when the front wheels are jacked up and turned I cannot reproduce the sound (speed not high enough?) but the brakes seemed to not rub evenly.
Nothing seems loose when moving front end components, no real play in the front wheels


I've gone and repaired or replaced a few components but the sound (albeit quieter) still persists.
All front wheel bearings were cleaned and repacked (minimal to no difference in sound)
Front rotors were warped and replaced with brand new (this made things quieter)

The brake pads seem to be wearing evenly (new pads in February) BUT the inside pad on both sides are worn on the inner section maybe 1-2mm of pad worn at an angle.

I am suspecting my calipers are sticking (there is a slight pull to the left) but both pistons seem to be pushed in relatively easily by a c clamp and while the hubs are not hot after a drive around the block, the rotors are.


Any thoughts?
Thanks!

[DexterH]

You said you cleaned and repacked the wheel bearings. Have they ever been replaced, inner and outer? About a month ago I replaced both front wheel bearings due to a similar sound/noise as you've described. If the racers and rollers are worn to a certain point, no amount of grease will stop that 'humming' sound.

At least thats how it sounded in my case, more of a humming and grew louder the faster I drove. If I continued using the vehicle without attending to that noise, I'm quite certain it would've then become more of a grinding sound eventually.

Turning of the front wheels while driving does add a bit more pressure against the bearings as the rear drive wheel pushes forward, so I suppose it would explain why the noise is louder while turning.

Ofcorse if I'm wrong about that, I always welcome wisdom and happy to learn more.

[GrinMedic]

I am not sure if my bearings have ever been replaced, from what I understand the bearings in the L300 are supposed to be pretty bombproof, although everything wears down eventually!

I replaced the calipers today as one side was definitely sticking (not seized... yet) and the noise seems greatly reduced. I am not sure if I am now just hyper sensitive to noises or not, so I will give it a few days to a week to see how things sounds and the rotors and calipers set.


Bearings are a definite high likelyhood source, do you know if you can just replaced the bearings or do you need to replace the inner race?

Bearings alone is a easy job, but I have no idea how hard it would be to replace the races as well?

[DexterH]

Replace the racers as well. Usually both are sold together anyways. The bearings pop out easily but the racers need some effort.
I didnt have the proper tool to get the racers out, but I improvised.
Once you got the hub off, its best to clean all the old grease out then place it on its flat side ontop of 2 pieces of wood. Position the wood so that the centre of the hub ist making contact with the surface youre working on, table or floor. I used 2 pieces of 2"x4".

Ok as you look down into the hub at the lower racer, you should notice 3 notches where you can see the edge of the racer. I used a blunt old chisel to fit in the notch and carefully tapped out the racer. Tap each exposed area of the racer in rotation once at a time. If you tap too much on one end it makes the racer harder to come out. You want to make sure it comes out evenly all the wsy around. You also want to give it a solid firm tap yet not so hard as to break the racer. Be sure whstever youre using to tap it out, doesnt have a sharp edge. Notice my chisel was blunt.

Providing youve successfully gotten one racer out, just flip the hub upsided down and proceed to the other.
considering the effort thats required to do this job, its a good idea to see if that seal on the back of the hub needs replacing as well. Ensure all old grease is cleaned out and replace with fresh grease to prevent premature wearing of your new bearings.

Good luck my friend!

[DexterH]

Forgive me for referring to the race as racers. It a habit I cant seem to break.
Ok I just wanna explain how I installed the new races on my van and it worked well for me.
If this method is wrong and anyone wants to let me know, by all means please let me know.

Firstly I placed the hub on a piece of board on my table just to prevent my work table from getting damaged. Not that any damage was expected, it was just a precaution.

It doesnt matter which race goes in first so assuming youre doing the smaller one first, get the old small race you had taken out. Lightly grease the surface where the new race is goin in. Be sure you position the new racer in the correct position so that the bearing can sit in after.

Fit the new race in place and sit the old race ontop of it, ensuring its perfectly seated on the new one all way around.

Using a small piece of 2"x4" wood (4" square is ideal), place it on the old race so now you have 'sandwiched' all 3 together, new race/old race/wood.

Use a small sledge or a heavy hammer (one thats manageable to use with one hand while youre holding the sandwiched parts firmly in place) and firmly tap the most centered spot on the block which would allow the race to receive equal force around its diameter. For each blow of your hammer, be sure to inspect the new race to ensure it going in perfectly straight and not twisted/slant.

It will take some time but the new racer will sit perfectly into its rightful position. Purpose of the piece of wood is to create somewhat of a cushion from the blow and prevent the shock from breaking the new racer while dispersing the force of the blow from your hammer.

This is my first attempt at giving details on a diy project, so if I have confused you in some areas, please forgive me.

REMEMBER! Continuously inspect the new race as youre tapping it down into the hub and be sure to hit the most centered point.



Good luck!

[GrinMedic]

Fantastic! Thank you for your help!

I've heard of people putting the new races in the freezer and then installing them, as they warm up they expand to the proper size and fit easily. I'll give that a try and report back!

The wood-old-new race method seems very clever as well, good have have a few options.

[DexterH]

Wow I never heard of the freezer method but makes alotta sense! If my wife saw me putting mechanical parts in the freezer, man i'd be dodging the rolling pin and every other kitchen utensil she can get her hands on.

I'll be watching for your progress

[almac]

I personally haven't done it, but from what I understand dry ice is very good for replacing races. it is very cold, but it takes some time. in the end, it probably takes less time then pounding them in.
you could just go out and buy a lisle race driver, and pound them in yourself. having the right tool REALLY helps. http://www.princessauto.com/en/detail/l ... -p2918514e :)

another great option, is to just take the disk off the van, clean it and the bearings thoroughly and take them to a shop. I'm sure they can press them in with little cost.

when you clean your bearings, dip the whole bearing into a can of brakekleen or grease remover. I don't recommend putting them back in without cleaning and repacking them. wash them well and inspect them for wear; I usually toss mine if they show any signs of wear(bearings are only around $20ea).
repack them with high temp bearing grease.
oh and definitely replace the inner seal, don't reuse the old one. they are also cheap. I'd rather replace now, than have to strip it all down later to do it again after finding a leak.

hope it works out for you! :D

[Growlerbearnz]

Huh. I just use a hammer and a drift- for both removal of the old ones and installation of the new ones. Removal's easy, as there are a couple of notches in the hub to allow a drift in behind them. Installation isn't too tricky either: as long as you're careful to start them off straight, and hit them alternately on opposite sides, they go in fairly smoothly.

The thing that told me my front bearings needed replacement was that they needed adjustment more often than usual- every 5000km or so I'd notice that the front wheels were a bit loose. Not unexpected for bearing that had done 200,000km I guess. The new ones have done 20,000km and are still nice and tight.

[DexterH]

Good to know all these methods that work.
As well as those that take less time than others.
I was and will always be worried about breaking a race while tapping it in. I kept saying 'hub' in my post when its actually the rotors.
The purpose of using the old race was because of the recessed area the new one had to go in. The extra height allowed me to ensure I was giving a more controlled blow of the hammer as well.

I live in a '3rd world' country though our economy is going ok. But alot of auto shops here charge hefty prices on particularly new parts. When they factor in shipping charges, taxes, profit, man its crazy.
Then theres the machine shops that also charge rediculously high prices for small jobs. It was one of the reasons I began doing things myself while learning along the way.

Online shopping is an option, but theres the risk of wrong parts being ordered/delivered particularly if one isnt quite sure about part numbers or if a replacement part could work. When you get it, you realise theres a slight variation which makes it unuseable.

[GrinMedic]

Well the new races and bearings went in without too much trouble! I used the 2x4 + hammer method to put the new races in since the freezing did next to nothing!



Unfortunately I did not seem to do much for the noise, which may have gotten quieter.

Since the bearings, races and seal change, the noise seemed to get a little worse with more audible clicking when at highway speed... until my power steering belt broke while parallel parking (that was fun...). Replaced with a new belt and the noise went drastically down... but is still present.

It is more of a humming or vibration noise that still seems to be coming from the front right. No steering wheel vibration, I can feel it below my feet. I'm not sure if it is still increasing while turning as the overall feel is less than it was.

I also noticed a minor clunk when removing my foot off the accelerator while coasting at highway speed, which led me to inspect the front driveshaft.

I think the rear U joint on the front prop shaft is loose, but It almost seems as if the front diff has fluid leaking from it (just checked the fluid, it's full and clean).

I'll replace the u joints and see if that works... otherwise any ideas??

[DexterH]

I suppose the upside is that you dont have to worry about front wheel bearings for quite some time, but I am sorry your problem still persists.

Im not sure if the velocity joints can such problems. Usually they do make a clack clack clack noise when they're going bad and very noticeable while turning. But considering yours is a humming vibration, drive-shaft sounds like a possibility. That clank noise you hear as you release the accelerator, that also sounds like a bad cross. A problem I also currently have although I replaced both front and rear crosses on my driveshaft not so long ago. Well actually I paid a guy to replace them for me as I didnt have the time and now I'm wondering if he did replace them or if I got scammed?!

Im not familiar with the 4x4 model delicas/L300 , but mine is the 2x4 model and carries only 1 long driveshaft.

Hope you get it sorted out soon. Safe weekend!

[Firesong]

It's your drive shaft.

If you have gone over the usual suspects (like I did)
and all the front end gear is solid including a wheel alignment .

Then check your main drive shaft. Go get it balanced and have the Ujoints checked.

I don't know why it causes the vibration in the front right quadrant but it drove me nuts.
We did everything lol..
Even removed the hubs, to eliminate the front end drive train.
Balanced the front drive shaft...
finally did the main and it was the problem... needed a balancing and ujoints.

Bingo!