Tires: replacing tires with different size, Chevy Suburban Tires

Question
I'm getting ready to buy all new tires for my 94 Suburban.
It has 245/75/R16 tires on it now.  The guy at the tire shop said I should put 255/75/R16 on it.  Is this a good idea?

Answer
Cori,

On every vehicle sold in the US, there is a sticker - commonly called the placard - that will list the original tire size and the proper pressure for that size.  The placard is usually located on a doorpost or in the glove box, but sometimes it is located in the trunk or on the fuel filler door.

I would not recommend that you use a tire size smaller than what is listed on the placard.  BTW, you need to pay attention to the letters in front of the tire tire.  Suburbans came with both "P" metric tires (for the light duty versions) and "LT" metric tires (for the heavy duty versions).  It is important to use the same type.  This has to do with a tire's ability to carry load, so this is a safety issue.