Submitted by lostonabackroad:
Here is a method I worked out to do the front toe adjustment and it is accurate...takes about 15 mins if you are just checking and the toe-in is found to be within specs. This method also could be used to do the rear toe if needed.
Probably as accurate as at an alignment shop...if you take care with it.
As far as your cars mileage...it's possible that poor alignment might cost you 1-2% in mpg...not to mention the increased tire wear.
Wheel alignment 101:
How to do it:
* Before starting: You need to be sure that your wheels do not have side to side runout...or your attempts to set the toe-in will likely be off. You can check this by rotating the front wheels and watching closely for any side to side movement...or you could use a dial indicator.
* If you have oversized tires...you will need to compensate for this as far as the diameter of the tire vs the OEM size...which are what the specs are for. This isn't that important unless you've made extreme changes in tire size.
* If your toe specs are given in degrees...you will have to translate this into inches at the tread. You probably wouldn't go wrong just shooting for zero toe or a slight toe-in with most cars.
What you will need:
* a small short laser level....around $10-$12.
http://www.harborfreight.com/ .....or some discount stores.
* a square aluminum or steel tube...must be very straight.
* 2 home-made bungee straps...made by using inner tube rubber & coat hanger wire....the length depending on the style of wheel. You will need to hook the ends in the spokes or holes in the wheel...and over the square tube.
* 10"² tape measure
* a 6"²... 2"³ X 4"³...not warped.
* 2 jack stands or similar STURDY supports
* pencil or pen
How to do it:
* Find a reasonably LEVEL paved area...this can be more difficult than you might think due to the fact that most paved surfaces are sloped for drainage...but perfectly level isn't needed...a decently FLAT surface is.
Even reasonably level packed gravel will work. In fact...a level and not too deep gravel surface might be the ideal...since the gravel allows the tires to slip...meaning that you can adjust the toe with the tires on the ground.
* Drive your car forward and STRAIGHT....slowly with the steering wheel held steady and stop it gradually using the hand brake. Shut it off.
* Using vinyl tape, tape the laser tightly (without tripod)...centered on the square alum tube. I use a wrap of tape at both ends.
Or use a lightweight steel tube and use the magnets in the base of the level.
> This tube must be very straight and uniform; and has to be cut at the right length to fit on the most reliably accurate surfaces on the face of your wheels....so that it always sits parallel to the wheels surface.
* Using the 2 bungee straps...strap the tube onto the first wheel at AXLE LEVEL using the vent holes in the wheel and in a close to horizontal position with the laser beam pointed to the front. Keep the tube reasonably centered vertically and horizontally; and check that is is sitting flat on the wheels surface on both ends.
* Place the 2 jack stands (or other supports) 2"² or so in front of the car at a right angle to the front/back centerline of the car. On these and AT AXLE HEIGHT, place the 2"³ X 4"³. Check to be sure that the distance from the axle centers to the 2"³ X 4"³ is the same on both ends. Mark the position of the 2"³ X 4"³ from the car on both ends using chalk on the paved surface you are working on.
* Align the laser beam so that it hits the 2"³ X 4"³ (it should be reasonably close to level...use the bubble) and use a pen to mark the exact CENTER of the light spot on the wood. I use a vertical arrow and the number (1) to start.
* Then, without touching or moving the 2"³ X 4"³ or the car, move the laser to the opposite wheel, being sure to place it in the same way on this wheel, and mark a vertical arrow centered in the light spot and labeled with the number (2).
You now have 2 marks at opposite ends of the wood.
* Now, measure the tread to tread width or the DIAMETER of the tire and multiply this by 4.
Set the jack stands and 2"³ X 4"³ up....out this (4Xs) distance from the first position...using the first chalk marks to measure out 4Xs the tire diameter at each end.
* Assuming that you haven't moved the laser or the car, adjust the SECOND arrow and the number (2) so that the laser beam hits EXACTLY on this mark. You will probably need to adjust the tube (laser beam) up or down to hit the arrow.
* Then, without touching the car or the 2"³ x 4"³, move the laser to the original wheel again. Mark the place where the laser hits with another vertical arrow and label it (3).
* Now....using a caliper (best) or tape measure, carefully measure the distance between marks (1) and (3). Then divide this by 4.
This will equal your CURRENT toe setting in inches....(+) or (-).
Adjusting the toe:
* It's best to have hit BOTH tie rod adjusting threads with penetrant BEFORE starting this whole process.
* The process of dialing in to the correct toe-in can be frustrating IF you don't make very small changes relative to your previous setting. Probably best to move the adjuster by no more than 1/8 to 1/4 turn at a time...unless your toe-in is way off. Do not try to guess or set it relative to the rear tires.
* IF your steering wheel is off to one side when driving straight down a road, then you would want to try and correct for this when you adjust the toe. You do this by turning one adjuster in or out on one side...which side...depending on where the steering wheel is driving straight ahead and whether the tie rod is in front or back of the axles.
Centering the steering wheel:
The steering wheel needs to be reasonably close to center in order for your turn signals to be able to cancel correctly.
Cautions: An inexpensive laser might not be very rugged...so you'd want to treat it carefully.
Obviously...DON'T look into the laser light...and don't point it at people.
The main points to consider in order to do it right are: be consistent each time you place the laser and tube on a wheel...mark exactly in the center of the laser spot...measure carefully between marks (1) and (3).
If you have hit a curb or had an accident...you'll likely need a professional alignment...since there are many other settings involved in a complete front alignment.
I also now use an additional method I found mentioned elsewhere on a forum where you use a 2x4 or 2x6 (depending on tire diameter) and a 24" level to do a preliminary alignment check.
With the tires pointing straight ahead...you place the 2x4 (or 2x6) narrow edge up...in back of the tires and using the level placed against the side of the tire...and scribe a line on each end of the 2x4 without moving it...using a pen.
Then do the same thing in front of the tires...only first carefully lining up a previous line on one side...then scribing a new line on the other.
Any difference in the last two lines (front to back) is your toe in / toe out.
This method isn't as accurate...and you need to watch the lettering/bulges and so forth on the side of your tires. But it's easier to do.