Adjusting toe

[Paul G]

The best way to adjust the toe is by measuring the distance between the back of the front tires, and the distance between the front of the front tires, and the fronts should be about 1/16" to no more than 1/8" toe in.

There are you tube videos of some guys adjusting the toe on the fronts, using parallel strings aligned off the rear wheels. Not a good idea I found out.

So I decided to double check the front toe based on the rear wheels, assuming they are perfect at zero toe. I set up parallel strings along the sides of the car using four jack stands, aligning the strings parallel off each of the rear wheels. Doing this I found that the rear tires are toed out. I would have expected the rear axle to be at zero toe?   

   

[A383Wing]

rear toe should be "0"....either you have a bent differential, or you are measuring wrong....are you using turn plates under the front wheels?

[Paul G]

No turn plates. I need to make a set, that would help.

When I had the strings set parallel to each rear wheel I measured the distance between the strings at the jack stands at the rear of the car, and measured the distance between the strings at the jack stands at the front of the car. The front was about 2" further apart than the rear. That doesn't tell me the actual toe of the rear, but is does tell me the rears are toe out. I should put my measuring bars on the rears and actually measure the toe out like I did with the fronts. It might not be that much? But I would expect zero.

[A383Wing]

I'm unsure about this, but usually the front track width is wider than the rear so the car tracks better, that may be your string issue here....I have never used the "string" method...I use a "toe stick" that you put at the front and rear of the front tires....or get a helper and use a tape measure and measure the center of the tread of the front tires at the back and the front...try to get the tape measure up as high to the tire as you can front and behind the tire....this should get you close...

[HPP]

I'm unsure about this, but usually the front track width is wider than the rear so the car tracks better, that may be your string issue here....

This ^^^^. Most don't realize the front track width is wider than the rear because we put much wider tires on the rear and this tends to mask it.

I think this may what your seeing. There also could be thrust issues with the rear axle as well that could create an offset when using the string method. I'd suggest sticking with the measurements on the front tires exclusively for toe.

Its rare to have a rear housing that is perfect. Most will have some small percentage of degrees in toe as well as camber. However, it is usually small enough to be construed as zero and ideally should be zero to avoid unusual wear on the  axle shafts and bearings.  However, I have know people that have bent and heated housings to on purpose to create toe and camber to aid in handling.

[Troy]

I use this:
http://www.amazon.com/gp/product/B004PJGWZ4?psc=1&redirect=true&ref_=oh_aui_detailpage_o07_s00

Troy

[c00nhunterjoe]

The most accurate method is to put it on an alignment rack. Toe is the last measurement to measure/adjust. 
    That said, i cant tell you the last time i saw a solid rear axle that was at 0 toe..... speed bumps, pot holes, accidents or just plain old years of abuse. They are usually close, but never perfect.

[Paul G]

The most accurate method is to put it on an alignment rack. Toe is the last measurement to measure/adjust. 
    That said, i cant tell you the last time i saw a solid rear axle that was at 0 toe..... speed bumps, pot holes, accidents or just plain old years of abuse. They are usually close, but never perfect.

This is what I was expecting to hear. I just assumed the rear axle would be straight. But after 40+ years, it aint straight no more, if it ever was.

Something to consider. When I push the car from the bare concrete pad outside the garage on to the painted floor inside the garage the tires used to squeak on the painted floor, all four tires squeaked. After the front toe adjustment, the fronts are quiet on the painted floor, but the rears still squeak. 

[c00nhunterjoe]

The most accurate method is to put it on an alignment rack. Toe is the last measurement to measure/adjust. 
    That said, i cant tell you the last time i saw a solid rear axle that was at 0 toe..... speed bumps, pot holes, accidents or just plain old years of abuse. They are usually close, but never perfect.

This is what I was expecting to hear. I just assumed the rear axle would be straight. But after 40+ years, it aint straight no more, if it ever was.

Something to consider. When I push the car from the bare concrete pad outside the garage on to the painted floor inside the garage the tires used to squeak on the painted floor, all four tires squeaked. After the front toe adjustment, the fronts are quiet on the painted floor, but the rears still squeak. 

That could be thrust angle, axle tubes, or even the front end causing the rear squeak. Not trying to sound like a prick, but the tapemeasure and string will only go so far.

[myk]

yeah, I thought that the rear wheels would only have thrust angle to be measured?  If they have toe in or otherwise, doesn't mean there's something wrong?

[Paul G]

I use this:
http://www.amazon.com/gp/product/B004PJGWZ4?psc=1&redirect=true&ref_=oh_aui_detailpage_o07_s00

Troy

That is a nice tool to have. Does it stay in place on the tire?

This is an expensive set up they are using, (links below). It is easy enough to make a tool similar to this from some angle iron, and cheaply.

https://www.youtube.com/watch?v=C5aItwp5w0s

http://www.summitracing.com/search/brand/quick-trick-alignment?GroupBy=ProductName&SortBy=Default&SortOrder=Ascending

[Paul G]

Thrust angle? How do you adjust thrust angle? Shim the front spring perches? How do you even measure thrust angle?

[c00nhunterjoe]

Unless its way off, you dont mess with it. Typicly something is bent of it is way out of whack. On unibody cars like ours, it could be the physical body twisted in the middle. You just counter it with front caster offsets.... for what its worth, a front end alignment shouldnt cost more then 100 bucks and these cars are not rocket science. It boggles my mind that noone can line these cars up anymore, or any car for that matter. All i hear is horror stories with classic cars and i frequently redo other shops work. My standard rate for an alignment is 99.95.

[HeavyFuel]

Track:

59.5" front

59.2" rear

[Paul G]

I measured the rear toe, it is 3/16" toe out.

As for the rest of the alignment. There is an old thread on this board where Chryco, Neal, says to set each front wheel for maximum caster first by adjusting the upper control arm rear bolt all the way in, and the upper control arm front bolt the way out, that maximizes caster. Then adjust for camber. To get the camber equal on both sides I used an angle gauge and straight piece of iron on the tire, top to bottom of the tire right in the center across the spindle, adjusting each tire to a few degrees negative camber on the angle gauge. Keep in mind the radial tire has bump out at the bottom, the bottom of a radial is out a little more than the top. By eye there is some camber visible, and both sides are equal by using the angle gauge. Then adjust toe last. 1/16" to no more than 1/8" toe in.

The car tracks straight.

[cdr]

I measured the rear toe, it is 3/16" toe out.

As for the rest of the alignment. There is an old thread on this board where Chryco, Neal, says to set each front wheel for maximum caster first by adjusting the upper control arm rear bolt all the way in, and the upper control arm front bolt the way out, that maximizes caster. Then adjust for camber. To get the camber equal on both sides I used an angle gauge and straight piece of iron on the tire, top to bottom of the tire right in the center across the spindle, adjusting each tire to zero on the angle gauge. Keep in mind the radial tire has bump out at the bottom, the bottom of a radial is out a little more than the top, that is why I used zero on the gauge. By eye there is some camber visible, and both sides are equal by using the angle gauge. Then adjust toe last. 1/16" to no more than 1/8" toe in.

The car tracks straight.

Thats how I do it   

[Paul G]

I decided to put my toe checking bars (which are just two 36" long angle irons) on my truck just for kicks. The rear axle, a Dana 60, was dead on zero toe. The front needed some tweeking to get it to 1/16" toe in. Might explain why the front tires were feathering little.