BUYING A TRUCK GEAR RATIO ADVICE

IDK, 2:64's sounds like flatland gearing. For any kind of hills, I'd think nothing lower ( numerically) than 3:50's.

 

2.64 rears are only part of the Total ratio combination and engine that matches it ...
The question is wayyyy too broad.

You see allot of modern engines with 2.64 and OD trans because the engines these days have a much lower RPM sweet spot and peak TQ.
Volvo for example makes peak TQ between 900-1050 on XE engines and generally about 1150-1200 on regular engines.
One of my trucks is a 2.47 with OD and the TC - XE motor, it pulls as well or better than other older trucks with 3.08-3.55 rears I've found.

455hp should be an XE spec, I'd recommend 2.64 - 2.85 in the regular XE engine, it's fantastic ..2.47-2.85 in the TC...
The 3.08 is for lower speed cruise(55-68 max) and generally not optimal against a High TQ/Low RPM motor that's ran at 65+ MPH regularly.

 

What is the gearing in the transmission? Is that a direct drive transmission?

 

Can someone explain again, please, why an inadequately chosen gear ratio would work adversely to the type of work?
What is really at stake? Wear and tear, mpg , climbing speed?
When defining specs is it that significant?

 

RPM vs Speed .... Fuel MPG and the wear on all rotating assemblies. Finite mechanical life

 

Overdrive.

The direct drive spec would be in the 2.25 area with a newer model Low RPM/High TQ motor

 

So Volvo; D15, I shift, running mostly in Midwest, weight 60 - 70...or more if reefer, 2.64 does the job done?

 

2.64 or 2.47 will work just fine. Most Volvos have a D13 Volvo engine.

 

My bad. I meant Volvo motor.Thats the only option for a new volvo other than cummins x 15 correct? So you could not really go wrong with the standard specs the dealers have?