Just bought a 97 blazer ls. with 38000 miles. Noticed the previous owner
changed tire sizes. org.were 235/75r15 to 30x9.50r15. How will this effe
ct my speedo & odo?I'm more concerned about odo. long term.
Any thoughts would be appreciated.

this link should be of use to you

Sorry, i forgot the link--duh! here it is

http://www.1010tires.com/TireSizeCalculator.asp

how come the calc doesnt work?...I put my blazer in there and no results

http://www.miata.net/garage/tirecalc.html

Try that