Which rear end ratio is better for a Volvo 780?

Answer 1

Really depends on year, engine, and what you're using it for. For a freight hauler running just a five axle unit, if you were to get a brand new one with the ISX, the engines of 450 horsepower or less for 2014 have their power band from 1250 to 1350 RPMs, so you might want to consider something like 3.36 rears with a .73 or .74 overdrive transmission, or possibly 2.93 or 2.85 rears with a .86 or .87 overdrive transmission. Then, there's always the I-Shift option, which is available only with a Volvo engine and comes with either a .9 overdrive ratio or a 1:1 direct drive ratio... If it were me, I'd probably go with the .9 and 2.64s, and just not use the big hole unless I was empty or loaded really light. But you should really talk to a Volvo rep about how to spec your truck... I wouldn't be the be-all, end-all source for that info... Volvo trucks aren't made for the lines of work I've been in.. they're aimed at freight haulers.