My 1991 came to town with a blown transmission. Our local GMC dealer traded for it and obtained a replacement transmission. I am wondering if there are other applications that will also work in our trucks. The reason I ask is that when going into reverse, the transmission shifter knocks the transfer case shifter into four wheel drive. Another problem is the speedometer is off, even though I replaced the way too short tires with 235/85R16s. It is about 5 mph off at 70, 75 on the speedo is about 70 on the ground. I could always apply a little gentle persuassion to the transfer case shifter to move it over half a knob or possibly they installed the t-case shifter incorrectly. Thanks, Glen