
There are two types of frames commonly used, the ladder frame or full length frame and
the subframe. Both frames are isolated from the body using rubber isolators. The
subframe does not run the full length of the vehicle. The subframe supports the engine and
transaxle. The subframe provides the mounting point for the front suspension lower control
arms. Any misalignment of the subframe (accident damage, improperly performed heavy
engine work where the subframe is loosened, lowered and/or removed, etc.) causes a
misalignment of the front wheels. Movement of the subframe usually causes an increase in
caster on one side of the vehicle and decrease in caster on the other side. This can cause
the exhaust system to bind up, problems with control cables and unacceptable noise.
Check the frame/subframe for any obvious damage, especially on a used vehicle with an
unknown history.
Setback
Subframe setback
Setback applies to both the front and the rear wheels. Setback is the amount that one
wheel spindle may be aligned behind the other wheel spindle. Setback may be the result
of a road hazard (heavily hit pothole, for example) or a collision. The first clue is a caster
difference from side-to-side of more than one degree.
Summary of Contents for TrailBlazer
Page 1: ......
Page 26: ...Fig 3 Typical body and undervehicle maintenance locations Refer to chart for descriptions ...
Page 29: ......
Page 30: ......
Page 31: ......
Page 175: ...Spring free length check Valve spring squareness check ...
Page 192: ...Front of piston mark ...
Page 361: ...5 3L Engine Except Saab Underhood Fuse Block 2003 2005 Early Production ...
Page 469: ...Removing the outer band from the CV boot Removing the inner band from the CV boot ...
Page 470: ...Removing the CV boot from the joint housing Clean the CV joint housing prior to removing boot ...
Page 471: ...Removing the CV joint housing assembly Removing the CV joint ...
Page 472: ...Inspecting the CV joint housing Removing the CV joint outer snap ring ...
Page 473: ...Checking the CV joint snap ring for wear CV joint snap ring typical ...
Page 474: ...Removing the CV joint assembly Removing the CV joint inner snap ring ...
Page 475: ...Installing the CV joint assembly typical ...
Page 553: ...9 Torque the lug nuts to specification 10 Lower the vehicle ...
Page 556: ...Toe in Frame Misalignment Frame misalignment ...
Page 588: ...Bleeding caliper ...
Page 624: ...Manifold gauge set components Refrigerant recovery recycling station ...
Page 676: ...A C Specifications ...
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