Treadwear
The treadwear grade is a comparative rating based on the wear rate of the tire when tested under controlled conditions on a specified government test course. For example, a tire graded 150 would wear one and a half (1½) times as well on the government course as a tire graded 100. The relative performance of tires depends upon the actual conditions of their use, however, and may depart significantly from the norm due to variations in driving habits, service practices and differences in road characteristics and climate.
See also:
Tire Rotation and Required Services Every 12 000 km/7,500 mi
Rotate the tires, if recommended for the vehicle, and perform the following services.
See Tire Rotation .
Check engine oil level and oil life percentage. If needed, change engine
oil and filt ...
Rear Axle
When to Check Lubricant
It is not necessary to regularly check rear axle
fluid unless you suspect there is a leak or you hear
an unusual noise. A fluid loss could indicate a
problem. Have it inspe ...
Repair Facility
GM also recommends that you choose a collision
repair facility that meets your needs before you
ever need collision repairs. Your GM dealer
may have a collision repair center with GM-trained
techn ...