Service & Appearance Care 
If  you  ever  replace  your  tires  with  those  not  having  a TPC Spec  number, 
make  sure  they  are  the  same  size,  load  range,  speed  rating  an\
d  construction 
type  (bias,  bias-belted  or  radial)  as your  original  tires. 
I CAUTION 
A 
Mixing  tires  could cause  you  to  lose  control  while  driving. If you  mix 
tires 
of different  sizes  or  types  (radial  and  bias-belted  tires)  the 
vehicle  may not  handle  properly,  and  you  could  have  a  crash.  Be 
sure 
to use  the  same  size  and  type  tires  on  all  wheels. 
I 
Uniform Tire Quarity Grading 
The  following  information  relates to the  system  developed  by  the  United 
States  National  Highway  Traffic  Safety  Administration  which  grade\
s  tires  by 
treadwear,  traction  and  temperature  performance.  (This  applies  o\
nly  to 
vehicles  sold  in the  United  States.) 
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 (1 1/2) 
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  var\
iations 
in 
driving  habits,  service  practices  and  differences  in road  characteristics  and 
climate. 
Traction-A, B, C 
The  traction  grades,  from  highest to lowesr  are:  A, 8, and C. They  represent 
the  tire’s  ability  to  stop  on  wet  pavement  as measured  under  controlled 
conditions  on  specified  government  test  surfaces  of  asphalt  and  concrete.  A 
tire  marked 
C may  have  poor  traction  performance. 
Warning:  The  traction  grade  assigned  to  this tire is based  on  braking 
(straight-ahead)  traction  tests  and  does  not  include  cornering \
 (turning)  traction. 
Temperature-A, B, C 
The  temperature  grades  are A (the  highest), B, and C, representing  the  tire’s 
resistance  to the  generation 
of heat  and  its ability  to  dissipate  heat  when 
tested  under  controlled  conditions  on  a  specified  indoor  laborat\
ory  test  wheel. 
Sustained  high temperature  can  cause  the  material 
of the tire to degenerate 
and  reduce  tire  life,  and  excessive  temperature  can  lead to sudden  tire 
failure.  The  grade 
C corresponds  to  a  level  of  performance  which all 
passenger  car  tires  must  meet  under  the  Federal  Motor  Vehicle  \
Safety 
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I CAUTION I 
A Using  the  wrong  replacement  wheels,  wheel  bolts or wheel  nuts  on 
your  vehicle  can  be  dangerous. 
It could  affect  the  braking  and 
handling 
of your  vehicle,  make  your  tires  lose  air  and  make  you  lose 
control.  You could  have  an  collision  in  which  you  or  others  could  be 
injured.  Always  use  the  correct  wheel,  wheel 
bolts, and  wheel  nuts 
for  replacement. 
I 
I 
I The wrong wheel can also cause problems with bearing life, brake cooling, 
speedometerlodometer  calibration,  headlight aim, bumper  height,  vehicle 
ground  clearance,  and  tire 
or tire chain  clearance to the body and chassis. 
A Putting a used wheel on your vehicle is dangerous. You can't know 
how it's been used or how many miles it's been driven. It could fail 
suddenly and cause an accident. If you have to replace a wheel, use 
a new GM original equipment  wheel, 
I 
Tire Chains 
rNOTICE 'If put vehicle has LT265/75R16 size tires, don't use tire chams; they i can! 
damage your vehicle. 
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