Gearing Delema
 

Ok, I have asked this on CF and TDR so I might as well here as well.. I just bought a 2012 Mega 3500 4x4 DRW Laramie with Max Tow. Chrysler mistakenly built the truck with 3.73 instead of 4.10. I tow 11,000 lbs and normally run about 73 mph which is about 1800 RPM with the 3.73. A lot of people really push the 4.10, which is why I ordered it. BUT I now see they are running slower speeds so about the same RPM.

Chrysler has offered to make it right so that is not a problem. Question is where do you get your best mileage towing at what RPM is the "Sweet Spot".

A friend has the 3.73 in his 2011 CCSB SRW and he pulls 8000+ same time of year and speeds as us with 11,000. He said he would never go with the 4.10 and says sees the same results with gearing in his semi trucking business that they have started getting lower numerically gears.

Opinions please. Also. I may be starting a new job soon and will have a 70 round trip freeway commute. Empty

I tow with 3.42's and get a long fine....and my trailer empty is 9500lbs;) Loaded is considerably more than the 11K you're towing....

I'd leave the 3.73's personally....towing sweet spot is different in each truck as far as mileage goes, but I shoot for roughly 2000RPM. That being said, while pulling my friends 44' enclosed race trailer at roughly 23K gross weight, my truck would hold 70mph just fine....even at the 1650RPM the 3.42's give me in 6th.

Chris

The 4.10 would give me the 2000 RPM at 75mph its 80 with the 3.73 which is too fast for sustained towing for me

Yes, but the 1800RPM would probably be fine as well....

Which will you do more, run empty, or tow 11K lbs??
Chris

Basing on old truck. About half. I put about 10,000 miles a year on old truck towing. If I get the new job I'm working on then I will probably drive empty more.

The 2006 5.9 auto with 3.73 that this replaced ran best power wise at 2000-2200. But did get better mileage below that. It just didn't have the power to hold OD very good. Obviously the new HO has way more torque available. The HO torque peaks at 1600 then begins to fall off where the 5.9 stayed flat after the peak as HP rose.

Question remains which is better for all around

You really don't have "Max Tow" then. Your assumed GVWR will not be accurate with the 3.73s. I'd get the 4.10s, unless you really really love the truck and that 70 mile highway commute empty is going to be the norm.

6.7L has more bottom end, and the top end isn't bad either.

I'd still go with 3.73's.....of course I have 3.42's, and I'm still always looking for a taller gear on the highway. I need an 18 speed to find the gears I want....

Chris

I would take the 4.10's in a heartbeat. If you paid for it, take it. Plus with the 4.10's and the double overdrive, that is a perfect gearing choice, esp for towing. I havent ordered mine as i am waiting for info on the 13's, but I built mine with the 4.10's and max tow in the dually. 2k rpms is the sweet spot for towing. I am guessing the 4.10's will raise you 100 rpms over 3.73's.

Well quit guessing....there are gear ratio calculators out the that will let you make an informed decision;)

I'll keep my 3.42's and towing MAX GCWR all day long.
Chris

I am keeping the 3.73. Chrysler offered a couple of options. One was to swap the axles and another provided a 5/100 Maxi Care warranty which I chose.

Chrysler was very good in accepting there was a mistake made and stood behind their product, even offering an option where I could have traded in and got a whole new truck. All in all I am happy.

why did you not get a new truck????? if they offered it, you should of took a new one...

Good choice on the warranty. I would have chosen the same. I'm getting along fine with the 3:73's. This tranny is awesome in my opinion and has so many ratios it goes through between the double OD and tow/haul mode that I haven't found a weakness yet. My heaviest trailer is only 10k though.

I did not know you could order the max tow package on a mega cab. I just looked at the 2012 towing info and found out as before the GVW has not been upgraded in 2012 and remains 10,500 lbs. With the 3.73 gears the GCWR is 20,300 lbs.

With 4.10's its 26,000 lbs. Quite a difference. Thats with the A6 Auto tranny and dual rear wheels.

The Long Bed truck's GVW is 12,300lbs. GCWR with 3.73's is 25,000 lbs and with 4.10's is 28,000 lbs. With A6 Tranny and dual rear wheels.

Dave

Fully loaded with everything I was 19,200 with the 06 Mega Dually so Im good...I am happy with the 10,500 because it keeps me under the 26,001 mark where I would need a CDL. My trailer GVWR is 14,000

I anly had about a 1000 miles on it at the time only 1800 or so now. It is new