Re: just got new rear end 5.57?
if you had a 6.5 before, then a 5.57 is a step in the right direction, but still not that desirable. I've had that rear end in 2 buses, and really wish i had a better rear, like a 4.44. i don't think you would want to go any more conservative than 4.10.....if you had a 3.73 for intance, depending on the powertrain your engien probably wouldn't produce enough torque to drive the bus down the road in top gear.
if i were gonna change out a rear end, i'd work hard to find a ratio between 4.10 and 4.44.
my bus with 5.56 was getting 6.5 mpg when phill with 4.44 ratio and the same size bus and same size engine was getting 10-12 mpg when we went on a trip together. It wouldn't take long to pay for the better gear ratio....especially with fuel above $4/gallon
Quis custodiet ipsos custodes (who will watch the watchmen?)