I have a 1992 GMC-15 Jimmy that has started giving me trouble. It still moves but while driving it feels like it is getting high RPMs and slipping. I checked the fluid level and it was fine. The fluid did have a "burnt rag" smell to it. Is this a sign the whole trans is gone or maybe a simple problem like the filter and fluid should be changed? I am not sure but I THINK its a 700R4 trans on a 4.3 liter non vortec engine and 4 wheel drive. Any help would be a good place to start