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What kind of weight and size will you be towing? I'll soon sound like a broken record around here, but when you talk about gearing, fuel economy, driveability, performance, etc., you're talking about having to make compromises somewhere at some point. You just have to pick your priorities in order and stack the deck to fit them. It's very logical to try and achieve the best in all categories, but it's usually a juggling act, and something will have to give a bit. The heavier the load you'll tow, or the bigger and less aerodynamically efficient the towed item is, the lower the gear may have to be. Plus, how big is your Ram? A full-boat, 4-door, 4WD, fully loaded pickup is going to suck some more power and fuel efficiency out of the engine and may also need lower gearing. My '12 Express 2WD with regular cab and short bed pulls my slightly-over-5000-pound travel trailer with ease with 3:55 gear. Your needs and results may vary.
 

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Best with stock tires (from best to worst):
3.92, 3.55, 4.10
Best with a level and 33's:
3.92, 4.10, 3.55
35's and up:
4.10, 3.92, 3.55

Now if you're looking for best fuel economy every day you're not towing then a 2WD 4.7l with 3.55's and a 6-speed
 

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Discussion Starter · #5 ·
What kind of weight and size will you be towing? I'll soon sound like a broken record around here, but when you talk about gearing, fuel economy, driveability, performance, etc., you're talking about having to make compromises somewhere at some point. You just have to pick your priorities in order and stack the deck to fit them. It's very logical to try and achieve the best in all categories, but it's usually a juggling act, and something will have to give a bit. The heavier the load you'll tow, or the bigger and less aerodynamically efficient the towed item is, the lower the gear may have to be. Plus, how big is your Ram? A full-boat, 4-door, 4WD, fully loaded pickup is going to suck some more power and fuel efficiency out of the engine and may also need lower gearing. My '12 Express 2WD with regular cab and short bed pulls my slightly-over-5000-pound travel trailer with ease with 3:55 gear. Your needs and results may vary.
My truck is a crew cab 4x4, and I will be levelling the front next week, 2.5 inch. I do haul during the hunting season, not often. It is an everyday driver. I’m trying to find the balance between performance and economy. I am currently equipped with 3:55 and no LSD (with the 4WD Auto) 5 speed. My fuel eco is terrible.
I will be inquiring with my dealership for an upgrade to 3:92, LSD, and possible 6 speed. What are your thoughts?
 

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I'm not trying to be a smart ass but I think you got your buying process backwards. I think you bought first then decided what you needed instead of deciding what you needed then went out and bought something that matched your needs. If you are going to switch both front and rear diff's to 3.92 and add LSD and then change from a 5 speed to a 6 speed, I think you should seriously think about trading trucks. Your probably talking about 5-7.5K---if you buy all new parts and have the dealer install them.
Jay
 

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Discussion Starter · #7 ·
I'm not trying to be a smart ass but I think you got your buying process backwards. I think you bought first then decided what you needed instead of deciding what you needed then went out and bought something that matched your needs. If you are going to switch both front and rear diff's to 3.92 and add LSD and then change from a 5 speed to a 6 speed, I think you should seriously think about trading trucks. Your probably talking about 5-7.5K---if you buy all new parts and have the dealer install them.
Jay
By upgrading I meant trading in for a 2012
 

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2011 models only have 5 speed transmissions

changing rear & front differential ratios to 3.92s can be costly
you will lose a bit more fuel mileage, but gain a little performance
 

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Sorry, I misunderstood your question. Also I realize that the 2011 have a five speed, I was guessing the cost of replacing it with a new 6 speed, if it could even be done.
Jay
 

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You will not ABSOLUTELY lose mileage with the 3.92. They multiple power and can actually make the truck MORE efficient, as needs less gas pedal to do the same work. Where the efficiency in the deeper gear is lost is at the very top end where the RPM of the truck can't settle as deep as it can with a higher gear (numerically lower).

Deeper gears (numerically higher) offer free power, yielding more responsiveness at all speeds and rpms. The LSD makes no difference.
 

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1.) You bought the wrong vehicle if you are worried that much about the mpg
2.) Your driving style and environment (how aggressive you are, local terrain, etc) make more difference than your gears.

To the OP, bottom line is this. There are people who say that whatever they have is best and you'll have a hard time finding ground truth in this (or any forum). After doing your research pick which ever combination of gears/LSD makes sense to you.

I will leave with this. I have a QC Sport 4x4 with 5-spd, 3.55 and no LSD. I travel back roads and city streets (light to light) to work and I routinely get 16-18mpg every tank. I love my truck and it does everything I've asked it to do. That includes towing a 6'x12' enclosed U-haul trailer (fully packed) and had the bed of the truck full at the same time. I live in Colorado and had to go up/down lots of hills for my move. I never had a hard time. These trucks work well (when not down for warranty items).

hope that helps
 
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