Level method for determining Toe In.
Basically what Iím doing
is placing a laser level against the outer edge of each of
the front rims and letting the projection fall on a surface
that is relatively close (4 feet) and then moving that
surface to a point farther away (7 feet) and marking the
I use a 2X4 board
propped up on two stools as the surface and I mark the
pinpoint beam projection (The red dots). I used a single
board. I actually moved the car backwards instead of the
You donít have to worry
about getting the boards (or board) in the correct
position laterally because you will be subtracting one
dimension from the other and dividing by two to get the
average. Just keep your marks straight
(which are the close measurements and which are the far
measurements). If you were interested in comparing the toe
in specifically on each side then you can use the laser beam
positioned on the rear wheels as a means to get the board(s)
in line laterally for each measurement.
My "a" dimension turned
out to be 1.3125" and the distance "b"
was 4' or 48 inches. So the toe in was the Arctan(1.3125
/ 48)=1.556 degrees (Way to big)
The Arctan is sometimes
displayed on your calculator as TAN-1
To get the toe in measurement as
defined by the manual which is the distance the front
edge of the tire is actually inboard from the back edge
of the tire.
You just need to use the angle just
calculated and solve the equation for "a"
using 25" as the "b" dimension" (My
tire was around 25" in diameter)
a=Tan(A) X b
In My case 0.68" Which is way
out of spec! it should be around 1/16"
- 1/8". I turned the adjuster rod on my front
end about 2 turns and I ended up with a measurement of
about 0.448 degrees (or 0.19" on a 25"