Rear axle misalignment..

I've posted this on another forum, but I figured I'd give here a try..

Well, in my quest to figure out why I get such nasty drivetrain vibration, I've gone through a lot of variables, and still haven't been able to pinpoint an exact cause, unless...

Last night, when I was checking out my rear tires, which have been only rubbing on one side (yes, I haven't rolled my fenders yet, so sue me..), I noticed that the Passenger's side sticks out nearly a half inch past the fender... I run to the other side, and notice that my 315/35R17's are actually a half-to-a-whole inch tucked under the fender.. WTF?!?!?!?

SO in my mind, my rear axle is pretty far off from what I believe to be normal. I would have never seen that much of a discrepancy w/ my old tires/rims...

Since I've swapped U-joints, had the rear axle rebuilt, and rebuilt again, complete suspension overhaul, NEW tires/rims, and new tranny mount, I couldn't for the life of me find out what was causing the vibration... Now I think I know..

Now here's the "meat and potatoes." Since panhard bars are used to center the rear axle on the chassis, this sounds like the only approach I have to straighten things out; no pun intended..

Question I have is, since I have a rear-diff girdle, it looks like a panhard may not work. Has anyone else used a panhard bar along w/ a rear diff. girdle w/ success?? Before I make the plunge, I wanna know if it'll work..

TIA


JT

Mine has the recessed load bolts, so I think I should be okay, but as was mentioned, the drain and fill plugs are going to be in the way I believe... Maybe not.. It may only need the torque arm removed...

What are your guy's impressions of the MM Panhard bar??

Does anyone make Watts Links for our cars?? If so, can I even use Watts Link w/ the Rear diff. girdle??


JT

Sweet.. I'm going to check out Griggs/Evolution, since I've seen the MM Panhard bar already... I'm willing to bet though, that I may not be able to use the Watts..

I really have to do something about this soon since I think my pinion gear is pretty much done.. After the fluid add the other night, the sound hasn't really toned down... What's worse, is that this will be the 3rd time in 2 years I'd have to rebuild the diff... I'm going to wait until I get the suspension/drivetrain issues ironed out..

Thanks for all the help guys...


JT

Currently, I have 3.73's w/ the Eaton 31-spline LSD, T/A Diff. girdle, and all of the other suspension stuff.. I was doing some research, and I saw that some of the newer Mustangs were experiencing some of the same problems, w/ bigger than normal axle offsets from the factory.

Excellent points.. I haven't checked the torque boxes, since I've been so busy w/ work, school, more work, then my other job... I plan on getting under the car tomorrow... As far as backspacing, I'll pull the wheels off tomorrow and measure it, although they seem to be pretty true. They also almost balanced out perfectly. Here's another point of interest...

I got into an accident last year, however, the vibration was neither worse, nor better than it is now... Originally, the shop who rebuilt my diff the first time, didn't bother to shim the diff correctly, and ate the bearings in a matter of a year.. I replaced U-joints and the tranny mount.. The tranny mount actually got rid of some of the vibration, but the U-joints, I think are no good. I get a squeak when the car shifts... I think it's just a big mess of the rear..

On top of this, I think the breather valve is stuck open, because I seem to be puking fresh gear oil (Mobile 1 @ $12 a quart, Friction Mod @$5, Sonofabitch) at an alarming rate.. Also, the pinion seal looks like it's leaking, due to the vibration, I can only assume..

I may also bring it to an alignment shop to see if they can at least get me some raw data to work w/..


JT

Well, I've never removed the dogbone, so I can rule that out..

Yesterday, I removed the rear wheels, and the backspacing is spot-on on both wheels... I didn't really get to dig too deep, as to the torque boxes, and hopefully, if it doesn't rain until later today, I can check them out...

3 days, and the rear axle is already out of fluid from the breather..



JT