Opinions/Advice needed

Depends on engine power and terrain you will be operating in. Gear it fast and run it slow.

 

I would go with 3:55 with 24.5 and probably 3:36 with 22.5.

 

I wouldnt run 3.55s on a DD15. 3.25 or 3.36 tops.

 

No, the taller the ratio the more torque you need, the lower the ratio like 3.55s the less torque you need. 3.36s will give you more top speed and allow you to turn lower rpms at a higher speed, thats what a DD15 needs.

On a side note, man if you want advice from a bunch of guys on a internet forum about trucks, then you shouldnt own any piece of equipment. You have been very lucky with 0 mechanical knowledge. Dont trust your hard earned money to someone who might be clueless about what they are talking about, this aint $100 were talking $100K

 

Salco...this guy knows a lot about what he's talking. I went through the same discussion with the Freightliner guys before I bought 2 Cascadias with DD15s. You will be please with the DD15's low end torque. I made the mistake and went with the wrong ratio.....

If your drivers tend to want to downshit too early, go with a 3.42.....if they can keep patient while climbing a hill and let the DD15 do its job, they will do great with a 3.36 or even lower (numberically). The fuel economy is good on our DD15s @3.58....but outstanding on the one our company bought @3.36...outstanding.

I would seriously consider the dual torque versions as well.

 

WELL PERSONALLY BRO I GOT CATS,CUMMINS,AND DETROIT~AND HAD A FEW MERCEDES ENGINES IF U WANT SOMETHING TO LAST 500K GET A DETROIT~ U SHOULD BE ABLE TO DO A INFRAME ON UR FREIGHTLINER FOR CLOSE 10K BUT IF UR GONNA BUY NEW GO CAT THERE GOOD FOR A MILLION BEFORE U NEED AN INFRAME ~ ANYWAY STAY AWAY FROM THE VOLVOS NOTHIN BUT TROUBLE ~IF U LIKE FREIGHTLINER GO WITH THE CASCADIA~