I am watching a 1999 Suburban 2500 2wd on ebay. I have been looking for a 97-99 2wd 2500 suburban with a 5.7 for some time. This truck is perfect for me but I am not sure about that 4:10 rear end. A broker has the truck so there is no information about gas mileage. I am wanting to stay about 17-20 mpg and I am not sure if that 4:10 will allow it. Anyone know?

If that 4:10 is going to to mess up my mileage can I just change out the ring and pinion to a 3:73 or something? Are there any computer changes that have to be made? Any sensors need changing?

Any information would be appreciated. I normally work on the older stuff so this newer truck has me baffled.

So far it looks like all you have to do is change out the ring and pinion and then have the computer re-programed.

Not sure wether to go with the 373 or the 355?

Any thoughts?

The gear set you choose should be determined by your intended use. Will you be towing anything? If so how heavy a trailer? I think you would have no chance of getting the mileage you want with the 4.10s IMO.

My 2004 Silverado SS has the 4:10 gears. It's AWD and has the 345hp, 6.0L engine. It is averaging @15mpg. Of course, that is not towing anything.

T