Hi! I currently have a 2003 2500 4x4 quad cab long bed truck with the 3.73 rear axle gear ratio and the hemi engine. I am noticing that the truck is struggling going up hills; On the straight away it does good. If the hill is steep enough, I'm lucky to be able to go 25 because even if I floor it, it downshifts really quick so I can't get any speed. A couple of people have suggested that I need a truck with a 4.10 rear axle as they said that would make a huge difference towing in hills. Here is the complete outfit: I have a 8' truck camper that fully loaded weighs just under 2000 lbs. I am pulling a 16' stock trailer with 2 horses in. The trailer, tack, and horses combined come in at a little under 7,000 lbs. Should a truck like mine but with the 4.10 rear axle be able to pull something like that decently? With all of the sales going on right now, it is tempting to get a 2009 since it has the increased HP and torque in the hemi. But I wouldn't want to spend the extra money if it isn't able to solve my problem. Do people think a truck with the 4.10 would fix my problem? Or will I have to end up getting a diesel truck for my outfit even though I don't go camping too many times a year? Any advice or help would be greatly appreciated. Thanks!

Aaron

Are you sure it is a 3.73? I didn't know Dodges had that ratio. I thought they just had 3.55, 3.92, 4.10, and 4.56.

What RPM are you running? Are you downshifting into direct/drive or even 2nd?

Yes, I just verified that the tag in my glove compartment box says it is a 3.73.

simple answer...yes. The higher the gear ratio, the sooner you can get the engine into peak horsepower output. although if you already have 3.73 (which as stated earlier, doesnt seem to be a dodge ratio), putting 4.10 in isnt gonna give you much. If you're gonna do a gear swap, just go with the 4.56. There are toooons of guys on here that swear by them (I'm gettin mine installed a week from today)

4.10's will help a little bit, and yes 3.73's did come factory in 2500 rams, I would try just changing your driving style, maybe manually downshifting the auto on the steep grades so it doesnt slam into first gear

yes, he's probably got a 3.73 ring and pinion, 2500's have different gears than 1500's. And to the original poster, if you were going to buy a new truck, I'd opt for the 4.10s, if I was going to PAY to have it done, not a big enough difference to justify the aftermarket cost, go straight up to 4.56s...

When I have the camper and trailer, I just keep it in drive and turn O/D off. I know in the 2009 truck that I looked at that it looks like there is a tow/haul mode and the capability to turn O/D off.

Depending on the severity of the hill, I need to floor the truck to get it to accelerate at all. This causes the RPM to get up to between 3000-5000 RPM but it doesn't stay there long before it downshifts and acts like it is hunting for gears.

I guess I'm confused how the 3.73 isn't a Dodge ratio as the 2009 truck that we looked at had an axle ratio of 3.73. Was there a period of years that Dodge offered the 3.92 instead of the 3.73?

For the people that have had the gears swapped out, where do you go? I've checked around several places local to me (SW Ohio) and everyone either hasn't done it or isn't confident that they can do it right.

Try driving in O/D off and in 2nd. Yes, the engine starts making noises that you wouldn't think a V-8 should make, but that's where the power is. I believe Hammer was nice enough to point that out to me. I pull a combined payload + trailer of about 8,000lbs and I get the truck running at 4,200RPM or so going up steep hills. Transmission temp, oil pressure, and engine temp all stay fine, but I maintain ~55 or so.

no 3.73 and 4.10 have always been the offered gearings in the 2500 series, these guys are thinking 1500s that's all. I'll try to locate a good shop in your area because an upgrade to 4.56 gears should solve your problems...