Gas mileage
 

My 2nd gen 4.3 is getting 10mpg with 31 in tires. This doesn't make sense to me it should be getting much better. Anyone have any idea why this would happen. Any input would be greatly appreciated.

Could be a lot of things. Full tune up, including o2 sensors maf cleaning, egr cleaning. etc

Thanks for the input Newguy. I will check all those things.

Possible fuel leak inside the plenum could also be a factor.

Would there be an oder of gas? Iwill look into. Thanks Thogert

I'd say do the tune up, then if it doesn't help, do the fuel leak down test that's floating around here on the forum.

Will do.