[marvinmycat]

I'm pretty sure I know what the problem is, but wanted some informed opinons first...

A few months back, I had a posi and 4.10 gears installed on my 98 auto. When the shop went to install them, I was informed that one of the axle bearings had spun, but the mechanic was 99% positive that he could fix the bearing and make it usable again. This shop does nothing but rear ends, so I trusted the guy. For two months I have been driving on the setup, and haven’t heard a single sound from the pumpkin back there.

Two days ago, I had my rear adjustable lower control arms put in by a professional mechanic. These are the Granatelli ones with the weight jacking system. They are also adjustable length-wise to accommodate moving the axle backward and forward. As such, this required that we measure the length of the old stocker LCA’s and adjust the length of the new ones to match.

Before the installation, the car would pull slightly to the right, but there is no tread wear going on up front at all. After the installation, the car seems to pull just a little more to the right, but almost to the point of not being any more detectable than before. Now that I have my rear seat out for the installation of functional side scoops, I can hear a noticeable whirring noise coming from the rear end, where like I said before, was quiet as a mouse.

Knowing that the car feels like it pulls a little more to the right, and now the new noise coming from the rear, do any of you think that the length on the right LCA should be lengthened just a bit?

Would a shorter LCA cause the driveshaft to be a fraction too long and compressed into the rear posi that this would cause some excess pressure on the unit, thereby resulting in the new noise?

I’m assuming that lengthening the right LCA would correct the extra pulling to the right as well, correct?

Associated with all the above concerns, I'm thinking that if the new LCA's werent' set exactly to the corresponding old LCA's, that the rear axle is now under a little stress being that it isn't perfectly straight. I didn't bother to take note of the where the axle connects to the pumpkin housing, so I'm thinking that the new angle that the axle connects to the rear might be the cause for the noise. Yes, no?

Any thoughts or suggestions are appreciated!

Update:

OK, I just got the right side LCA lengthened one full turn, and the car now tracks exactly as before. However, that whirring noise is still there. The tire pressure is the same or correct, if you will. I'm wondering if I lost some gear oil in the pumpkin, but when I look at the entire assembly and axles, I see no indication of leakage anywhere.

Any suggestions other than take it in to be looked at, which is what it looks like I'm going to have to do?

And now a new devolpement:

The rear left brake is making a horrid howling noise at medium pressure, and the tires chirp when making a tight circle in either direction in the parking lot at work where they never made that noise before.

Thanks!

[Typedef]

I get a noise similar to this while turning sharp in parking lots, especially in reverse. I have a 97 auto. My noise seems to be comming from the front end though... well the whiirring noise anyway, I have a creak in the back shock. I haven't got it fixed, it's been about a year now, I was told it was a ball joint, but I'm not sure.

[marvinmycat]

Aside from the fact that your post has nothing to do with my problem, your problem lies within the front, and you should get the ball joints replced. Steeda makes some really nice X2 balljoints.

My problem is with my rear diff, pinion angle, and/or brakes.

[Mustangdewd3.8]

Could be the traction lock that causes the chirp...

But is that your bakr sensor going off... or is it just a high pitched noise like your rotor is really glazed and needs to be regrinded or replaced...and if the sensor is going off... it makes like a constant like flapping noise it's a really annoying sound. could be a break pad the came loose... a shin that broke... Brakes are a ***** look at it.

[marvinmycat]

OK, after being up 24 hours, I took the car into the shop that put the LCA's on after work. Mind you that this job was done on the side and off the books, thereby saving me a butt load of $$$.

Anyway, it turns out that when we reused the rear brake cable brackets that were on the stocker LCA's, we had to bend them a little so they would fit into the pre-drilled holes on the new LCA's where your sway bar would go (a future mod!). The cables were a little tight and when I got the car back home, I bent them up higher to get some more slack in the brake cables.

This didn't do anything for the noise I was hearing. The noise, to be more specific, sounded to me like the noise you would hear on earlier ricer models of synchromesh running on low gear oil. Or it could be described as two pieces of metal being rubbed together in a circular motion. I was convinced that it sounded like the gears, but it turns out that both the brake cables were tight and weren't releasing the brake pads from the rotors all the way. Also, wit the back seat out, the sound would seem to come directly from in between the two front seats, making it appear to come from the pumpkin under the car.

We took the brakes apart, cleaned them up, re-greased the calipers, and cut one of the brackets off the LCA's. The guy could get the nut off as I used my super human strength to put them on, so I told him I'd take them off and fabricate something up to replace them and not waste anymore of his time.

Went for a drive and the sounds wasn't quite as loud, being that only one bracket had been cut off, but the louder than hell brake groaning when I applied the brakes was gone.

The chirping I heard was due to the brake cables being tight and not releasing the pads enough, thereby causing the tire to skip when I was in my company's parking lot which uses a finer pavement than the crap the streets are made out of, making it easier for the tires to chirp when I made sharp turns.

So, after three hours of in the shop, my constantly asking questions, the identified the problem, and now I've got a little work to do. Also, I will now be able to change my own calipers and rotors in the future! The cost? Free!!! These guys rock!!!!

If you put gears in and you think that they may be going, I was told that you would not mistake them for anything else as it sounds like a school buss grinding to a halt (FYI).

Thanks for all your helps guys, just thought I'd at least share some of the information I got this morning with all of you in case someone else needs it!

BTW, these LCA's rock! There is no more wheel hop or the car's back end loosing traction over the bumps when traveling at high speeds on NY's lousy highways! Get some, what a difference!!!