Hello everyone

Looking at buying a 2012 HO mega cab.


What is the best mpg unloaded rear end gear ratio? I assume 3:42

For towing, will the 3:73 provide better mpg?

For those that have a 4x4 2500 mega can with 3:73's, what mpg have you seen unloaded on the highway? Hand calculated, not overhead fool-o-meter

Thanks
Scott

 

Max I have gotten, deleted, hand calculated was 22.7mpg with the stock air box. I have 3.73 gears. I personally would not go with the 3.42s. Check out rambodybuilder.com to explore the different options for max trailer weights based on different trans/gear ratios.

Sent from my DROID X2 using Tapatalk 2

 

Auto or Manual? it makes a huge difference. I have owned trucks with Manual 3.73's and currently Manual with 3.42's, I personally would run 3.42 is you run a manual but the Auto runs real nice with 3.73's, I wouldnt want my 6th gear RPMS any lower than they already are. Hope this helps.

BM-

 

Auto - I am looking at a longhorn which is only offered in the auto.

Does anyone know the final drive ration of a 2004.5 48RE truck and a 2012 2500 6 speed Auto (not the Aisin)?

By knowing this, I can compare my current truck with 3.73 to the 2012 with 3.73.

I never thought I would say this but I think I want the 2012 to have a 3.73. 3,000lbs more towing capacity is peace of mind. I assume the 3.42's are lower in towing capacity simply due to the stress from starting from 0mph. I can not see how the stress would be more when you are moving.

 

The 3.42 ratio on the 2013s has got me really confused. The 5th and 6th gears in the 68RFE were already both overdrive ratios. Now the truck is geared even taller? To top it off, the stock tires are now 275-80s instead of 265s - so that gears it up even more. Sounds like the mpgs are great- so I guess I shouldn't question it. But yeah, seems like that famous Cummins low-end grunt off the line will suffer.

 

I purchased a 2011 sales brochure which was pretty helpful for towing capacities, options, lenghts, etc.

A 2500 4x4 crew with 3:42 was something like 9700 lbs towing where as the same truck with the only change being the 3.73 rear end increased the capacity to over 12K lbs. That is really surprising to me.

Tonight I will have to google the tranny ratios and do some calculations on RPM at highway speed.

I am not too concerned about it - I currently have 3:73s with 285 70 17 Nitto dura grappler tires. I can say that the tires ate 1 to 1.5 mpg compared to the conti's factory 265's.

Looking back, I should have stayed with the smaller tires. The nittos are great for load capacity, wear, and look cool but eat mpg.

For the next truck, I am seriously thinking about 17.5 vision wheels that can handle 5K lbs and 245 70 17.5 commerical tires that can handle over 5K lbs.

 

When I put 285s on my 2011 the mpgs didn't drop at all, but they dropped 1.5-2 mpgs average on my 2003.

 

That's a great question you're asking.

I ordered my 2014 Ram CC 4x4 8' Laramie Limited Plus 6.7L Asian 3.42 in October 2013. I'm towing a 38' #16,000 5wh RV in the East and have no trouble at all. That being said, I've not had to tackle any real mountains bing in Eastern U.S. admittedly.

During my order process my Dealer printed off the tow capacity for my configuration and max 5wh tow capacity was #17,000. Obviously, this was a real concern of mine and I needed the buffer. GM and Ford 3500's will fall significantly short on this so if you like those brands be prepared to go more stout if you plan to tow at or above where we are.

BTW - I love it! Smooth, very quiet and powerful. Oh. It looks good too.