Rear Toe Adjustment Cost

[mikewags]

A friend of mine was telling me that he knows of a shop that uses computers to check your alignment : they then "pull" the car/suspension to correct where it is off.

I'm not quite sure what he meant by "pulling it correct", but it sounds like bending it back correct. In this instance, I guess they would pull the right rear wheel hub outwards and correct the toe issue.

It sounds rather shady, and not the proper way of fixing this issue - then again, I just might be explaining it wrong. He says it's quite common and his alignment guy recommended it.

Just wanted to throw it out there (not considering it at this point...)

Edited March 24, 2009 by mikewags

[jmortensen]

A friend of mine was telling me that he knows of a shop that uses computers to check your alignment : they then "pull" the car/suspension to correct where it is off.

I'm not quite sure what he meant by "pulling it correct", but it sounds like bending it back correct. In this instance, I guess they would pull the right rear wheel hub outwards and correct the toe issue.

It sounds rather shady, and not the proper way of fixing this issue - then again, I just might be explaining it wrong. He says it's quite common and his alignment guy recommended it.

Just wanted to throw it out there (not considering it at this point...)

You need to have adjustments available to change alignment. Trying to bend parts to fix the problem doesn't sound right at all. I would suggest that you only "pull a car" to fix it if the frame is bent and the pulling is done on a frame rack.

[jmortensen]

Its not a common problem. I've found two or three rear struts with this problem and I've probably fondled over 100 rear struts so far. It might also not be a manufacturing problem, more of a race use, bending problem. One of the struts with the mis-alignned spindle pin holes came off my 1970 race car and probably had 25,000 track miles on it between the PO and I. The problem was masked by offset rear LCA bushings.

This would be a last thing to check if you're not able to get a good alignment.

Jeromio had this issue and I don't think his car was ever raced. I've seen it come up several times now since you alerted me to it.

[pbagchi]

Hey everyone! new to the board here. I actually have pretty much the same exact problem in my '75 280. This thread will really help me. I'm gonna pull the suspension down this weekend and see if anything is visually bent.

I already dropped the car with Tokico struts, Eibach springs, and installed a urethane bushing kit. I'm not sure if the toe problem existed prior to the drop, but if it was there, the drop definitely made it more pronounce. I was looking into the eccentric bushings as well...

I'll update with my findings, and keep an eye out here. Thanks!

[moritz55]

Hi, I've been following this thread and have taken a look at my rear end. I had all the bushings replaced with urethane and a new differential mount installed along with all new u-joints almost 2 years ago. Everything is very tight and no "clunking" during shifting and no noises or vibrations - really smooth during all aspects of driving. Since this work - I have about 3000 miles on the car.

PROBLEM:

I got to looking at car an noticed that the Passenger side wheel appears to be more "Forward" than the Driver side wheel? Passenger wheel clearance from front of rear fender to tire is 2" where as the Driver side measures 2-3/8". There is a 3/8" difference which seams quite a bit and thus noticeable. I took the measurements about 2" above bottom of door lining it up with the decorative body crease.

Note that the car sits pretty level:

Driver Rear Fender height - 26-1/4"

Passenger Rear Fender height : 26-1/8"

QUESTIONS:

1) Can someone confirm some dimensions for me from the attachment(not of my car , I only wish) I have included? I measure Front = 14-1/2" and Rear = 14-1/2" . Zero - Toe In design if all is aligned correctly?

2) I'm wondering if the Rear INNER Transvere Link Brackets are worn or bent slightly causing the Passenger to be outboard more?

3) OR my Rear Suspension is ROTATED slightly such that the Driver Side is 3/16" to far BACK and the Passenger Side is 3/16" to far FORWARD? I think this may be the problem... I'll be dissambling the rear end this weekend.

Any insight and advice is welcome.

Many thanks...

Rear End 240z Labeled2.doc

Edited August 26, 2009 by moritz55

[moritz55]

Well - if anyone is interested - I uncovered the problem in my rear end suspension after disassembly.

The Rear Link Mount Braces were BOTH bent 3/16 inch - toward the passenger side of the car(the 2 Black vertical braces holding the Rear Horizontal Transverse Brace Link in place - in the photo attached). These were not Perpindicular to the Body Member they attached to. This caused the Rear Horizontal Transverse Brace Link to be shifted toward the passenger side by ~ 3/16 inch. ALSO - the passenger side Rear Link Mount Brace was bent Forward by ~3/16 inch which made my Rear End rotated a bit as well. This caused the passenger side rear wheel to be More FORWARD and the Driver side rear wheel More AFT relative to the body.

My Attempted Solution:

1) I'm having a more rigid Rear Link Mount Brace design fabricated up for the 2 vertical braces.

2) I'm also having the holes slotted (2 upper & 2 lower) in each brace so it gives me the ability to Center the Braces if need be relative to the Rear Frame/Body of the car AND also allow me to have more Positive Camber Adjustment by enabling the Rear Horizontal Transverse Brace to be moved UP ~1/4inch from stock position. This upward adjustment should improve my Negative Camber by ~1.5 degrees to allow for my wide tires better.

Once the Rear Braces are finished - I'll put some photos out showing the Stock ones (which are bent and not as robust) compared to the New Ones with Slotted Holes for Camber Adjustments.

Many thanks .. stay tuned.

Rear End 240z Labeled2.doc

Edited August 31, 2009 by moritz55

[jmortensen]

What you'll really be doing is adjusting toe, not camber, since you can't move the bushing cups in front (they're welded into the frame). You only need to slot the bottom and then make a turnbuckle and get rid of the stock link. Here are some examples of different implementations:

http://forums.hybridz.org/showthread.php?t=89111

[moritz55]

Thanks Jon... I pulled up the link and there is a ton of good information. My vertical braces will have the Top Holes slotted on both sides... it allows me to center the Rear End so it's square with the body (similar to 1st pic from the link you sent me, but on both sides of the vertical braces).

The lower holes in the brackets I'm having fab'd up are on the same vertical braces, but slotted Up/Down. This allows the rear lower horizontal brace to move up/down, but staying square in same 2(two) planes that affect Toe-In and Alignment. This results in only Camber movement for the rear wheels. I only need up to 3/16 inch of positive Camber which is not a lot to improve the rear wheels. I'll get them all posted hopefully tonite if my brackets are done.

I appreciate your input and response. Hope you'll see this when I get my pictures posted. Please stay tuned ...

Edited September 1, 2009 by moritz55

[jmortensen]

Sure thing, this is one of my favorite topics of conversation about Zs, though I have to say I'm still thinking about what you're going to do and not understanding how it will work. You still can't change location at the front of the control arm. So I'm thinking that changing the height of the back only would allow you a little adjustment of pro or anti-squat. I think you would get pro-squat by raising the rear link. I think anti-squat could be had by lowering the rear control arm attachment points. The camber will be affected by changing the angle of the control arm, but very minimally. I'd suggest camber bushings if you want to adjust camber and don't want camber plates. Just by way of comparison, the camber bushings have about 5/8" of movement front and back if memory serves, and they adjust camber by about a degree. I don't think you'll be able to move the control arm nearly as much by changing just one end which is why I think your adjustability will be minimal. Changing the height of the control arm on the back end will also introduce a twist into the arm, which is a bad thing. The stock arms are flexible enough that this probably won't be too much of an issue for you, but strictly speaking it's not the best idea. More on binding control arms and solutions to that problem: http://forums.hybridz.org/showthread.php?t=129154

[moritz55]

Yes.. I think you are right. I'll only get very little adjustment, maybe 3/16 inch maximum. At least I should be able to center the rear end squarely which is a major improvement.

The specs for the car are as follows:

Camber: 20" +/- 45' (+ 65' ; -15' ) = ( +1.01degrees ; -0.25 degrees)

Toe-In: 3/32" out ; 7/16" in (roughly +0.22 degrees ; -1.00 degrees)

As you may have guessed my parts were not quite ready last night. Today I'll pick them up and get some posts of the picks. Last night I spent a lot of time leveling the car relative to the garage floor as best as possible to minimize vertical "plum-line" measurement errors. And then marking the floor for squareness relative to the front wheels and car frame/body. This should help me effectively lineup the rear-end so that it's square relative to the front wheels and body before I do any adjustments. With the floor marked I should be able to measure Toe-In and Camber as I move the horizontal rear transverse link brace up and down and side-to-side. I'll try to also do a sktech of my measurements so it's better visualized.

I've attached several photos of the markings and car on jacks before I begin to re-assemble and take measurements.

Thanks again...

Edited September 2, 2009 by moritz55

[moritz55]

Okay Jon .... I picked up the New Rear Vertical Braces with the slotted holes. I've attached the photo showing them - they are the 2 (two) center ones (next to the 2 original ones) just above the Rear Horizontal Transverse Link Brace. You can see they are wider, I have a gusset added down the middle and they are made of 3/16 inch thick stock(slightly thicker than the metric material used).

I'll start the assembly process later this evening.

Stay tuned...

Edited September 2, 2009 by moritz55

[jmortensen]

They look good to me. Only question I have after seeing them is: will the bottom of the arched part of the upright hit the link preventing you from using all of the adjustment in the slot?