Knurled wrote:

BrokenYugo wrote: Could negative camber in a stick axle be explained by a worn wheel bearing? Do the rear tires match? Were tire pressures checked before the alignment?

Axles can bend, and after they've been on the road a while they usually are bent a little. Almost every solid axle RX-7 that I've had on a rack had about half a degree of negative camber in the back, both sides Granted, they're a thin sheetmetal stamping, not thick tubes pressed into a cast housing like whatever flavor of Dana is in a Volvo.

Right, but why is one side positive?

In reply to BrokenYugo:

Could be the center casting is twisted in the tubes, driveshaft forces would tend to twist it thisaway which would cause negative camber on the left and positive on the right.

I'd be just as inclined to think that the alignment machine's heads aren't precisely calibrated.

Either way, a tenth or two of a degree of camber falls into "noise" and I wouldn't even consider it. It isn't going to hurt anything, and even if it was real and not a measurement error, there's nothing you can do about it anyway even if you wanted to, so why even think about it?

Ah, well my axle definitely kicks when I go from sitting still to drive. Car will pull to the right then later on in the day decide it wants to pull to the left. So axle def moving around. Im gonna think it's the panhard bar because that's like real easy to do.. after that I have no clue because every damn bushing is new in the rear along with shocks and springs.

It can't be the Panhard. Hell, I've driven a three link and a four link with that linkage broken off and it doesn't cause a pull, just a sensation that the rearend is skating around.

I did have a funny power-on/-power-off torque steer that turned out to be caused by one of the links bolts being loose.

Also, bear in mind that new bushings doesn't mean good bushings. Especially if you replaced rubber bushings with polyurethane bushings, those can cause all sorts of weird problems because they go sloppy very fast, and can be sloppy when new depending on the design.

Knurled wrote: It can't be the Panhard. Hell, I've driven a three link and a four link with that linkage broken off and it doesn't cause a pull, just a sensation that the rearend is skating around. I did have a funny power-on/-power-off torque steer that turned out to be caused by one of the links bolts being loose. Also, bear in mind that new bushings doesn't mean good bushings. Especially if you replaced rubber bushings with polyurethane bushings, those can cause all sorts of weird problems because they go sloppy very fast, and can be sloppy when new depending on the design.

Hmm, all the bushings were the expensive Volvo OE rubber. What else could it be then? The rear end is so darn simple on these things.

It's going to be 2 or 3 if it's a bushing. Potentially one of the axle tubes could have spun in the housing, but that's really thin. Anorexic.

Knurled wrote: It's going to be 2 or 3 if it's a bushing. Potentially one of the axle tubes could have spun in the housing, but that's really thin. Anorexic.

3 was replaced with a OEM bushing ($44 each). Nightmare to do by the way, it was my first real wrenching experience and I started at 4pm and ended at 4am... #2 I decided not to replace since it's a solid bushing and had no play in it.

whoa dunno why my text is all awesome looking

thrust angle will cause the car to dog track but won't cause a pull.

Nascars do it on purpose.

As someone who's done hundreds of alignments, I'll start by saying you can have the specs so incredibly messed up and it will still drive fine, especially if it's a more softly sprung car. Considerably stiffer suspension type stuff is far less tolerant of the alignment being off.

The thrust angle is nothing to worry about. Hell most trucks have a tolerance of something like 1 full degree.

What about bushings 6/7 in the diagram? Am I correct in thinking it has two upper control arms?

The panhard bar will almost never cause a pull unless at crazy angles or you have some other weird stuff going on.

I noticed you said in a later post that it will randomly pull in either direction? Generally I've seen this caused by binding stuff in the steering or suspension up front... could be tie rod ends, upper strut mount, etc. I had this happen on a 2013 Camaro that drove me nuts for a few hours. I ended up disconnecting the tie rod ends from the knuckles, and moving either side independently(without the rack attached) I found the right upper strut mount bearing was sticking badly. It would primarily pull to the left, but occasionally would do it to the right as well.

edit: I'll only be about an hour away from you at NCCAR next weekend. Saturday I'm overseeing timing and scoring but otherwise am free that day... driving on Sunday. Sign up here as a spectator(it's free) if you want to come out and watch some lapping, and I can take a look at your car during some down time. NCCAR Gripfest

Front suspension binding is probably happening as I went with some strut mounts that were after market since the rubber ones now are garbage. It's more for racing setup and I think my springs are running against the tapered area they sit it.

Oh man next Saturday? I'm probably free. Been wanting to check out the Mazda anyways since I do like them;

I has an MG 1100 that the trailing arms bearings/bushings were shot.

Sometimes the steering wheel would be off to the right, other times it would be off to the left

Never pulled either way, just that in order to go straight I would have to hold the wheel one way or the other.

In reply to Coldsnap:

Have you seen the turbobricks 240 coil over thread?

http://forums.turbobricks.com/showthread.php?t=85793

if you are holding the wheel like that.. I would start looking into your front suspension. Something is worn out or loose

I just put a good $450 in the front suspension ; strut mounts, tie rods, ball joints, struts, springs, bump stops

steering rack?

Coldsnap wrote: I just put a good $450 in the front suspension ; strut mounts, tie rods, ball joints, struts, springs, bump stops

Yeah, but are the parts still in good shape?

Also, none of them have loosened up or were installed incorrectly?

A worn steering rack or box/idler arm can cause issues like that. Some have a way to adjust the gear lash to reduce slop as the parts wear.

Worth looking into at least.

OK, steering rack is definitely old and probably on the way out. I'm going to chase down the rear end clunk this weekend and will report back.

I've fixed many cars that pulled by fixing the thrust angle. And fought many unevenly-loaded Ford vans that would pull right no matter what you did because of the high thrust angle because the left side was sitting lower than the right, no matter what you did with caster and camber up front. Plumbers and pool companies overload the trucks with built-in toolboxes and it all sits on the left side where the side doors aren't.

The front suspension centers to the car thanks to the SAI. The back end must be straight before you can even look at the front end. Industry guideline is no more than .15 degree but I've found that .10 is more like it.

Gotcha, yea that's my plan to sort the rear before addressing the front. Good thing is that everything is new so its just a matter of refiguring how things are...

Coldsnap wrote: Oh man next Saturday? I'm probably free. Been wanting to check out the Mazda anyways since I do like them;

Yep.

But MAKE SURE YOU REGISTER as a spectator, or you will not have access to the facility. I'll gladly let you take the 2 for a spin when we leave for lunch or something. I'm not driving on Saturday, I'm doing the HPDE on Sunday... I'm just doing the timing for Saturday with the club. And swapping wheels/tires at some point since I won't be driving down on the tires I intend to burn up on track.

I'll be hanging in the timing and scoring trailer most of the day, so if you can't find me just look for the fat guy screaming at the laptops.

REGISTER HERE:

NCCAR GRIPFEST REGISTRATION

It's free... So just do it even if you think you won't come out. If you change your mind you won't be allowed in if not registered. IIRC you have my phone number, call if you have any questions.

YMMV, but I have been amazed several times on AE86 Toyotas (which are solid axle, two lower plus two upper trailing arms, with a panhard rod) by handling/alignment quirks as a result of bad bushings that looked fine.

One of my cars used to have axle tramp, but the others didn't. Pull the rear suspension apart, everything looks okay. So I put it back together, and the problem continues. So I replaced some of worst looking bushings, but not all of them, and the problem gets a tiny bit better. Finally, I decided to replace the "just fine" bushings and found that they almost fell out of the control arms, compared to the "slightly-worn-looking" bushings that took a hacksaw, a torch, and a hydraulic press to remove.

Just saying, it might very well be the "seems fine" #2, or #6 and #7 bushings in your diagram.

Knurled wrote: Shame on the alignment shop for not seeing the bad bushing. A complete tire and suspension inspection is the first thing to do before you even hang the heads on the wheels.

This has been the thought running through my head. Seeing that thrust angle, the tech should have been on the case trying to sell you a fix. Did he not do a verbal walk-though after the work?

NOHOME wrote:

Knurled wrote: Shame on the alignment shop for not seeing the bad bushing. A complete tire and suspension inspection is the first thing to do before you even hang the heads on the wheels.

This has been the thought running through my head. Seeing that thrust angle, the tech should have been on the case trying to sell you a fix. Did he not do a verbal walk-though after the work?

Yea know this is sort of a frustration with this car is when I do bring it into service on something I can't do I feel like I don't get the best work / attention because the car looks like it was pulled from a junkyard. But oh well.