I currently drive a 2004 Ram 1500 QC 4x4, 4.7l 5spd. It has the 3.55 gears with a tow package. I tow a travel trailer weighing about 5500 pounds. It tows ok, but the hills kill it and more than 55mph on the hwy is almost out of the question. I am thinking of doing a gear swap. Would the 3.92s suffice or should I go with the 4.10s? How much mpg difference do you think I would lose? What brand of gears should I use?

Thanks in advance for any help.

 

4.10 for stock or near stock tires, 4.56 for any tire size larger than 33"...

 

I have the 4.7 and the 4.56 gears.

 

I Have 4.7 With 4.56's. Wouldn't Have Gone ANYOTHER Way! As Hammer Said, Not On Stock Tire Size. With Your Manual Trans Thats What I Would Recommend With Larger Tires. If Your Keeping Your Stock Tires 4.10 Would Be Still A Wee Bit Overkill But Worth The Towing.

When It Comes To Towing With The 4.7 Your Motor Has To Work SO Much Harder With The 3.55's That, In My ExperienceMy Gas Mileage Increased Due To The Gears Sharing The Load.

My .02 and Experience

 

How much mpg could I expect to lose with the 4.10s?

 

Lose? You should gain mileage... Everywhere except highway speeds in excess of say 75 mph you should see a gain in fuel economy. The 3.55s are on the truck mainly for emmission ratings to make the government happy. Lower rpm's at a given speed = lower emmissions. They'll also give Dodge Trucks a better fuel economy rating, in situations where the conditions are controlled. At a constant speed, no hills, basically cruising, they'll rate a mpg or two better than say 3.92s. They are a joke, performance wise in pretty much all real world driving.
You'll accelerate quicker, with less throttle from a dead stop, so city/in towndriving should yield you better economy by at least 2 mpg.

 

I have an 04,4x4 Quad cab,Hemi.with the 3.55 rear and 17 inch tires. My mileage isn't too bad when towing. I pull a 3500 lb boat with a tantum wheel Load Rite trailer .I don't know what the trailer weighs in at but it can carry 7900 lbs. So far I'm getting around 13.5 towing. and it has the towing package. It's got plenty of power

 

Out of curiosity, what size tires you got on those 17" wheels?
You've also got a lot more torque than jw's 4.7, as the Hemi can overcome having a 3.55 ratio much better than a 4.7L V8can.
I was perfectly satisfied with my stock 3.92 gears when I ran stock and then 33" tires, but I noticed a big time performance loss when I lifted and went to 35" tires. The 4.56 gears got me back to where I was with the stock tires, or maybe a hair better, performance wise.

 

I have an 03 Hemi 4wd QC w/ 20's. the truck came stock w/ 17's and 3:55's. Once I put the 20's on my truck became a dog, even more so than w/ the 17's.

I should have my truck back tomorrow w/ fresh 4:10's and a LSD. I cant wait to drive it. I will report back w/ results.

4:10's or 4:56 will work fine, if u tow 5500lbs a lot, u might want the 4:56. I know a lot of guys run motive gears and detroit tru trac LSD and have been very pleased. Mine is getting all mopar parts.

 

Brandon, how much for labor? If you don't mind me asking.