jemorgan3

I've been riding around with my new mosier 9 inch and love everything about it, feels solid, the 3.89 gear feels better on the highway than the 4.11 in the 10 bolt did by far..... but I have lost about 5-6 MPG's average over the 3 tanks I've burned since finishing the install!! With a 10 bolt and 4.11's i averaged 25-26 mpg's and now average 19-20 mpgs on a good day. Same exact driving style, same exact route to and from work, just far less fuel efficiency

I know the 9 inch is a heavy weight compared to the 10 bolt, but should it lower my MPG's this much???

4bangermustang

iTrader: (24)

takes more HP to spin.


Did you switch from an Aluminium drive shaft to a chromoly one also?


Prob has more to do with the rotating mass then it being a 9"...

bigger axles, bigger(in overall size) gear, etc..


on mine I took 4.5" off each side, alum center section, all the lightweight options. I swapped a bunch of stuff at the same time and seeing as I don't daily drive it, I don't really pay attention to gas millage.

Tis why I keep preaching the MWC 9" is great. Super light and super strong!

Bob@BruteSpeed

iTrader: (16)

No, it shouldn't lower your mileage by any significant amount. If it would, people would be installing nine inch rears and reporting lower mph's at the track, which they don't. A new rear is going to use more power to turn it that one that is fully broken in. Combine this with the possibility that you're now running a Winter fuel blend, and I can see you using more fuel. Bob

jimmyducati

iTrader: (3)

That all makes sense, didnt think of the winter fuel either. It did take a month of working on it for a half hour at a time so they very well could have switched fuel blends around here. I just broke 600 miles so ill be changing the gear oil soon, hopefully it loosens up and I get some of my mileage back.

Checkmate

iTrader: (2)

10bolt 4.10 vs 9inch 4.10 mileage is the same.

25-26mpg highway
18-20mpg mixed