Installed a 82 GSL rear end and now makes a grinding noise (metal on metal sound) I put new gear oil/lsd additive, new rotors, new pads, new wheel barring* on pass. side only apparently the other side was fine, installed a junkyard driveshaft same year as lsd.

Now I have heard that people say LSD are designed to make more noise then the open diff it replaced, but this grinding noise doesn't seem normal- the noise gets more intense the faster I go- the noise sounds like its comming from the passenger side- when the brakes are applied it stops then comes back. I have searched and am starting to think that I need new u-joints or the axle is bent, anyone else have an idea to wtf is up with this sound

 

i guarantee you took the two bolts holding the brake caliper and switched them. they are two different lengths, check the backside of your rotor and there should be a nice score where the bolt is hitting the rotor, the outside edge if i remember right. don't ask why i know

 

No I don't think thats the problem I had a mazda dealer and professional tech do the brake service and I don't think that he would let that pass.
Thanks anyway- anybody else got .02 they wanna throw in

 

well you didn't say you had a tech* do the work

 

'Professionals' make mistakes in all job categories - look at physicians.

This also sounds like brakes to me, so you better get that rear wheel off and have a look yourself.

Some people insist that 'critical work' (like brakes) need to be entrusted to a competent mechanic, but my belief that anything that critical to ME, should be done by ME - since that mechanic is probably NOT looking at what they're doing for about an hour out of their day as any kind of CRITICAL issue for THEM.

Follow my drift?

 

Lots of mechanics make mistake which is why they have insurance, its an easy job to check the bolt isnt contacting the rotor.

 

Could be the bolts,thats an easy one to check.
Bearing noise that goes away when you apply brakes sounds like a wheel bearing.Mine did the same thing years ago,changed the bearing and it was gone.The caliper gripping the rotor cushions the axle/rotor assembely and limits the bearing play/noise.
A good LSD diff will not be any louder/quieter than an open diff,unless its chattering,and thats in a turn.In straight line travel the LSD isnt doing anything.It and the differential only operate during a turn.In straight line travel,the power goes directly from the pinion to the ring,to the side gears/axles.The carrier internals stay put until theres a change in wheel speeds(turning).

 

I've had both problems. I found an 83 lsd and put in the widebody, before it was wide, and the rear end sounded like it had sand in it, stole the lsd out of one of the 85's and had no trouble. When I installed all new brake rotors, the fronts were even Brembo slotted, I mixed up the bolts on all 4 brakes and now have grooves on all 4 new rotors. It had been so long since I had taken them apart, I forgot about the difference. Damn I was pissed. Funny thing was, I could hear the rearend when it was bad, but couldn't hear the the brake rotors being grooved.

Check the rotors, if it's not them, try flushing the diff and fresh oil. If that doesn't work, you will need to pull the diff for service.

 

Everybody makes mistakes but I had one of the best rotory techs who works for mazda in the country working on the car so I am in full trust of his work so lets not question that anymore.


What do u-joints sound like when they are going bad?
I bought a driveshaft from a wrecking yard that set around for who knows how long and I think my problem might lie there but they could be totally cool idk.

 

you sure it's not your wheel/axle bearings? when a car get lowered too much the wheel/axle bearings begin to whine too. either that or it's high mileage and just needs replacement.

iirc, 84-85 rear ends only for for those same years. ditto for 83 and below.. you can't interchange those years.

 

I've just had the exact problem in my 82, allmoast grinding sound that you'd swear was the diff! so i changed the center and while on the job noticed the rotor bearings were completly rooted and so replaced them too. long story short- i think it was only ever the bearings and now i gots myself a spare diff center. change the bearings or atleast look at them cos i think thats the problem, good luck, check the inside of the rims at the rear for oil/grease
it may be the axle bearings.
If you got the work done in a shop, take it back for them to fix, just an idea.

 

Yesterday I put 30 miles on the car to see if the sound would go away after driving a bit, but the qrinding/squealing is still there. I am going to jack it up and get underneat it and check it out and find out whats going on

 

Ok so Today was the first day I could get the 7 jacked up off the ground to look at it, and what did I find? The ******* handbrake cable has been rubbing on the outter edge of the wheel and grinded through the rubber shell on the cable and made a big grove in my wheel. I also found something else kinda funny but the cable was zip tied to the frame of the car so Im guessing it wouldn't rub, lol. I would expect a little more out of a professional working at a dealership.

 

they are the roughest of them all, go to the little known mechanic thats been arround for a while cos he might give a **** about getting you back as a customer, big names are big probs, the only thing mazda motor corp in australia is good for is parts when they order the right parts ( even with the vin these guys get it wrong).
I did the bolts wrong on the calliper last night and am too laZY TODAY TO FIX IT......lol
Have to drive the **** hyundai today...lmfao!