If this has already been covered, maybe you can point me in the right direction.

The VN5600 6 speed manual has a 0.73 OD ratio and the G56 originally came out with a 0.79 OD ratio, which raised the RPM quite a bit at highway speed. For 2007, the G56 supposedly has a 0.74 OD ratio for lower RPM, but did they come out with the older 5.9L engine in the beginning of MY2007 or only with the new 2007.5 6.7L???

Thanks

 

My truck was manufactured on 11-16-06 and it has the .79 OD ratio.With my camper the gears work out pretty well. Without the camper,I could use some 35's.

 

I have no knowledge of the G56 with a final OD ratio of .74. Can you please cite where this came from? I'd like to learn more. Thanks!

 

I think that the new cab and chassis got the new .74 ratio in the G56 to make it more friendly towards 4.10 gears. At least I know I read that somewhere.

 

Where can I get the higher overdrive gear? These high RPMs are driving me nuts.

 

What gear ratio do you have? Even with the G56, you should be running fewer rpm's with the tire size listed in your sig line.

 

The G56 is only available with 3:73 rears from the factory.

 

There is a 3.42 ring and pinion comming out at the end of may or early june here is the contact info:


We actually have 3.42's coming in very soon. We have a long list of people waiting on them and expect them to go quickly, so we are excepting pre-orders. The gears are MFG by AAM and run $370.


Regards,

Carl Montoya



JT’s Parts & Accessories

Specializing in Differential Parts & Service

406 S Wenatchee Ave

Wenatchee, WA 98801

509-888-AXLE

866-349-6801 toll free

carl@justdifferentials.com

www.justdifferentials.com

www.ringpinion.biz

 

I only want to change the O/D gear ratio. I think I might go to a 35" tire also. I liked my ford 6 speed but when I test drove the Dodge we just went on a side road by the dealer and I never had the truck in 6th gear. I didn't realize til I was driving home that I was revving so high. Oh well, at least it's got a Cummins.