My question is should a 1997 Limited get the same Mileage as a 2001 SR5. Both have 3.4 auto trans and 2 wheel drive . All things being equal

Maybe if Everything is identical? Meaning rear end ratio, tires, brakes (degree of drag-all have some), road, ect, ect.....

Then weight, are both identical weight? Both waxed evenly? haha!

My wife has a 2001 SR5 that runs great it has a JDM that just purrs. I built a 1997 for my sister inlaw blown head gasket with only 180,000 miles so I had the valves ground compression was very good but I don't remember what they were before the grind but i'm sure its better now. We drove both about 500 miles to drop off the 1997. I did not pull the mileage for the 97 but the 01 got about 21 mpg. The 97 was noticeably thirstier at the pump. So did 97 limited have different Ration in the Rear end? Just wondering if any of the long timers here know what the answer is?

I have an 01 SR5 that got 21 mpg before I blew the head gaskets from overheating it due to a bad radiator cap and a 98 that gets 16 mpg by the odometer but it has beefier off road tires and the 01 has stock size tires which are more road style. I figure the tires make a lot of difference plus there's probably a difference in the calculation. It may pencil out to 16 but in reality due to the larger size tires it may be 18 or 19.

Then there's tire pressure, quality of gas, air filter condition, new plugs in the 01, etc. etc. Just lots of variables. If I were to take a longer trip in the 98 I'd probably up the pressure from 32 to 36 psi even though the ride would be a little rougher just to get a couple mpg's better.

The 97 was all up to snuff including Tire pressure new air cleaner new sparkplugs the car was to far away for me to do any work on it after it left my care but the mileage was noticable. I don't think there was anything not right with the 97 it ran wonderfully. As does the 2001 I just can not put my finger on the difference in the mileage, that's why I went to the big knowledge pool of 4runner.org to become enlightened.