Alignment - Toe-In Information

85saab03

FILE IN. S.I. Man. VOL. I

SEC. 6 PG. 22

Service Information

SUBJECT: MEASURING TOE-IN USING MECHANICAL, ISSUE: 10/85-792 OPTICAL, AND ELECTRONIC EQUIPMENT

APPLICATION: All Saab 900 Models



A mechanical toe-in gauge such as the one shown at the right is a mechanical device which measures front or rear wheel toe-in at the rims. When measuring toe-in, technicians must note that the specification given in the Saab Service Manual (Sections 0, 6, 7) are given for use with such a tool.



When using an optical toe-in gauge or an electronic alignment machine the technician must remember that these machines are not measuring toe-in at the rims. Electronic and optical gauges take an angular reading and convert it to a linear measurement (millimeters or inches).

For this reason the equipment manufacturers have standardized all toe-in measurements by using a universal circle of approximately 28 inches. A toe-in reading of 2 mm at the rims becomes 3.5 mm when measured at the 28 inch universal circle.
When using an electronic machine or an optical toe-in gauge (almost all alignment machines fall into this category), your technicians or sublet shops must use the following specifications.


Mechanic Optical/Electronic Machine
(measured at rims) (measured @ 28" universal circle)

Front Toe-In 1-3 mm total 1.7-5.2 mm total

Rear Toe-In (M79-85) 1-3 mm per side 1.7-5.2 mm per side

(M79-84) 2-6 mm total 3.5-10.5 mm total
(M85-) 3-5 mm total 5.2-8.7 mm total