I know this is K5, but the drive train is the effectively the same on my suburban... have a 91 1500 4x4 that's too little truck to pull our new camper. Have found a set of 4:10s/14 bolt FF & matching 10 bolt front (huge brakes on these).. for a reasonable amount ($100 each).... and can swap to get things where it'll pull the camper (also a new set of 8 lug rims/tires.. found a factory set @ $520). or...... found a deal on an 87 454/3:73 3/4 ton... in reasonable shape for $18K Can't deceide on what to do here! Like the newer one! (has a few more options than 91, ABS, CD, Rear defrosters).... but need an outside opinion?