Tires: 4 year old spare tire, 20 inch tires, dodge ram

Question
I have a Dodge Ram P/U 44,000 miles. need new 20 inch tires, they are expensive and would like to buy three new and use the fullsize spare. Spare is same tire and has never been used, however it is 4 years old. The tire looks perfect. Do tires age if you don't use them? Do you think this is a good idea? or should I replace all 4 brand new and keep the spare as is.

Answer
Anthony,

Rubber deteriorates over time and there is an increasing amount of traffic from manufacturers on the subject.  Lack of use (or wear) does not stop the aging process.

Some manufacturers are saying that you should remove tires at 6 years of age - others say 10.  I think the difference in the positions is the way they are looking at the question - and it comes down to heat history.

If you live in a hot climate - CA, AZ, NV, NM, NV, TX, and FL - then 6 years . If you live in ME, MN, MI, ND, or WI, then 10 years.

States in between are.....ah......in between.

Another consideration is the placement of the spare tire.  Was it right next to the exhaust pipe?  If so, that means the tire was artifically aged by the exhaust heat, and it might not be suitable for anything other that a temporary spare.