[A/S] Fw: M/S vs A/T tires

["Carol and Oliver Filippi" <ofilippi@xxxxxxxxxxxxx>]

Hunter,

The A/T tires are very macho, but I would only choose them if I
anticipated off road travel or use in mud or very deep snow. With a 4 
wheel drive, it is amazing how little traction you need to keep going 
when you have power going to all four wheels.  The driving wheels do not 
have to overcome the resistance of two passive wheels as in the two 
wheel drive configuration.

Note that the aggressive tread pattern of an A/T tire has less rubber in 
contact with the road, so you have LESS traction on dry pavement than 
with the M/S tread.  Also, the A/T will wear faster due to the reduced 
rubber contact surface and the negative effects of increased heat 
buildup.

Heat is a major cause of tire failure and is caused by rubber flexing.
The more rubber you have on the tread, the more flex and, hence, the 
more heat generated.  That is why race car tires have a relatively thin 
tread (at least those for dry pavement).  [ You can easily prove to 
yourself how stretching rubber generates heat by stretching a rubber 
band and then putting it to your lips.  Be careful you don't burn 
yourself.  It can generate that much heat!]

The heat generated by the macho tires Firestone made for the Ford 
Explorer was a key factor in the subsequent tire failures.

If most (or a significant portion) of your driving is on the Interstates
at 60 to 75 MPH, the M/S are a much better choice. [I would lean toward
 optimizing my tires for highway performance and safety.]  Also, the 
wear on an aggressive tread tire at high speeds will be greater and you 
will have a more difficult time keeping them balanced.

However, who am I to tell you what kind of tires you should pick for 
Bruiser?

One thing is certain, Michelin is the preferred truck tire.

Oliver  Filippi