Hello, i have a 2004 2500 with the hemi. We do alot of towing with it (its a business truck). During the summer often hauling a good 10000. i know sometimes we over do it but anyway, we would like to get something to boost towing performance. I have the banks monster exhaust and a k&n cai installed. btw, i love the combination we increased horsepower quite a bit and also the full mileage doesn't fluctuate as much. whats the next thing that i could do? we put about 150000 miles a year on it and about 90% of that is hauling probably. is a tuner the way to go? and if so what would best fit my needs? idc about quarter miles or raw performance. only towing. whats your suggestions?

 

A tuner is always the best. It'll unlock some power and I think for an 04 it can also do some transmission changes too. If it's 2wd, re-gearing would probably be worthwhile too. I'm thinking 4.56's if the 2500 comes with 4.11 to start with.

 

Most 2500s come with 3.73 gears stock, which IMO is poor for towing with a Hemi which makes it's power so high up in the RPM band. If it were up to me, they would leave the 3.73s as stock on the diesel trucks (which have the low end torque to handle that gear ratio) and give you the optional 4.10s as standard with the gasser.

GEARS will do a LOT more than a tuner for straight out pulling. If I was gonna buy gears, I'd go past the 4.10s and straight to the 4.56s myself. Dunno what the rated caps are on the 2500s, but a 1500 Ram's towing capacity increases by 1000 - 1500 lbs. when going to 4.56s from 3.55s or 3.92s...

 

Do they have the same stock tire diameter as a 1500? If so, whoever decided on 3.73s on a truck designed for work was an idiot!

If I wasn't 4wd I'd be looking into it already. I'm never on the highway and if I was, a few hundred rpm wouldn't affect cruising mpg anyway.

 

I agree gears would make a huge difference!

 

Get a Diesel.

Putting a 150k on a year is some serious towing.

 

That's exactly what I was going to say...even if it is a typo and 15K towing miles a year. I'd certainly hope it is not 150K towing miles a year as you'd only get about 2 years out of the truck and to spend all that money just for the truck, let alone all the mods to make it better for towing.

 

lol, my bad that is only 15k a year so its not that we put a crazy amount of miles but thats mostly towing. now we do some highway miles without a load, would that be hard on the engine with the higher gears? is it a big job to change gears? something i could do myself? if we are pulling 8-12000 lbs would the 4.56 gears be the way to go? and will that be a problem with 4x4?

 

oh also, everything else on this truck is stock except for the cai and exhaust. 17" rims nothing big. would this affect the gear's performance? is there anything else that i could do in conjunction with the gears that would optimize this setup i.e. bigger wheels etc?

 

There is a BIG belief that going to taller gears puts a strain on the engine at highway speeds, but this is FALSE and even more so with a truck that has a transmission that really has TWO overdrive gears. You should find that going to even 4.56 gears still only yields rpms between 2000-2200 rpm (depending on tire size), which just happens to be the sweet spot for the Hemi engine as far as balancing power with fuel economy. The taller gearing WILL have the engine working harder, but we are talking the difference between 1700-1800 rpms vs. 2000-2200 here, well below any threshold where the Hemi will even break a sweat. The good thing is, at this sustained rpm rate, the load will be MUCH easier on the transmission, as it won't have to "search" for the right gear nearly as often. Acceleration will be snappier when pulling weight, making merging into traffic & passing much safer, not to mention you'll need less throttle for pulling hills, which will save gas.

If the tire size is stock and the weight pulled is only moderate and you do a good bit of highway driving unladen, then I'd probably opt for 4.10s. But if the weight tends to be high (5000# or more) or if you really aren't concerned with losing about 1/2-1 mpg fuel economy when traveling 70 mph+ on the interstate with no load, then I'd step right up into 4.56s irregardless of tire size (yes, the larger the tire, the more gear you want).
If you are not experienced with setting a ring & pinion (especially in an AAM axle that must be shimmed) then this is one for a professional, and I'm not talking the average garage mechanic here. This needs to be done by someone who sets gears on a fairly regular basis.
Of course with a 4x4, you'll have to do both front & rear gears, otherwise the first time you shift to 4WD, you'll have to get the flatbed driver to go back for your transfer case in the middle of the road after he loads your truck up...