I have a 99 GMC Jimmy Sle 4x4 with transmission problems. Haven't had a chance to have it looked at but it barely shifts gears and goes beyond 30mph sometimes it will kick into gear and get up to speed if I ease on the gas. I quit driving it because the last time I did it wouldnt go past 25 and when I pulled over the engine was extremely hot and kind of smelled like burning oil but i think was from driving it at a high rpm. it still starts up fine and my 4x4 also grinds when i put it into gear but that has always been the case since i had a new tranny put in it. i had someone tell me its my transfer case causing the problems and could be even more to do with the transmission or even the motor and someone else told me its probably just my catalyic converter.. Does anyone know what it could be?