Hello all. It seems that my blazer is falling into the obsolete parts category. Im tryin to find the Speedo gears 15t & 40t for my Blazer (700r tranny), the dealer says its obsolete and cant get em, ive tried speedo shops and called a couple tranny shops, each keep telling me to try the other one. Anyways, my speedo is 20mph off while doin 50mph. I installed 4:10s gears from the 2:73s that were in there previously. Any help is appreciated.