MPG

Cummins... Volvos are much more expensive to repair... theres more to overall cost than fuel economy.

My 379 has a lifetime fuel economy of 6.33... tuff to duplicate even with an aero tractor.

 

Krooser, 379 # 6.33 average! Are all your runs down hill? Just kiddin, thats impressive.

 

That's the last info off the ECM... it's a few years old but not much has changed. I do pull a reefer now instead of a flat but I still do 6.0 if I behave myself.

All those high fuel economy claims are mostly smoke and mirrors IMHO. My 435 Cat will get better MPG than most any tractor pulling a van... it's pretty simple. And how about a cross wind... a flat top pulling a flat is a lot less affected aerodynamically than a condo with a 53' van... again IMHO.

If we all drove in a wind tunnel the most aero package would be the best... but in the real world there are too many variables.

 

Go with the ISX. I've got the D12 & I believe it's original design was for it to be a boat anchor

 

I Think I get 6.5 - 7 MPG with my 04 Volvo VNL630.

 

Go with the ISX. I had one in a 630 for 2 1/2 years and averaged over 7 mpg that whole time. And it was reliable unlike the Volvo motor and service network.

 

I saw an amazing video put out by Volvo when they introduced their first big diesels... pretty amazing how they are assembled mostly by robots... a very slick production that ALMOST made me want to buy one.... for about 2 seconds.

 

The shifters in Volvo's are not set up for short people. Drove one once, and just about threw my shoulder out trying to reach 4th & 8th.