I'M GIVING IT UP ON FINDING REPLACEMENT TIRES (TRACTION TREAD DESIGN) FOR 18" SPLIT RIMS.
They do not exist according to everyone I have called (per a lot of suggestions, thanks): Miller Tire/Ohio, Lucas Automotive/California, Wallace Wade/Texas, Coker/Tennessee, Fairmont/California, Fyco Truck Parts/Utah....(and about 6 other shops around my area in Montana).
I can find the highway tires 18x700 but not the traction tires which I need for the rear dually set-up.
Looks like I will have to change the rims. This will be a challenge as well. It may take a few weeks, but I will update this post with the results.
TIRED-OUT!!
