Gas Milage Tips And Mods?

[MVR 155]

Originally Posted by Harley_Daze

interesting reading of everyones take on mpg,..the first thing that comes to my mind on fuel consumption is axle ratio,..has anyone went to a higher axle ratio?..seems the 6.0 engine should propel the Hummer adequately with a 3.73 or a 3.54..comments?..

A taller gear (lower numeric) axle ratio would most likely cause mileage to suffer around town and possibly pick up a bit on the highway, towing mileage would suffer the worst, a taller gear would make the vehicle work harder till it achieved a given speed. At highway speeds in windy conditions you may also get worse mileage.

Great exaple of this is we just traded a 05 Eddie Bauer explorer in for the H2 last week, it was a V6 with 3.55 gears, got 15ish around town and 18-19 on the highway if you kept it under 75, towing a trailer netted us down in the 12-13mpg range and if you broke 80mph count on it going down in the low 17's high 16's....... My father owned basically the same truck with 4.10's and it got way better mileage than ours with the 3.55's around town and on the road, he even got better mileage towing a 8x13 enclosed motorcycle trailer than I did towing a 2 place jet ski trailer with ours. Point is once you reach a certain point going to a taller gear can hurt your overall performance and economy.... this could also be true with going to low for gearing. I believe that the 4.10's in the H2 are right at home and most likely deliver the best overall performance and economy