Hey guys,
I am thinking about regearing my truck for towing purposes and i wanted to ask you all your opinion.

Right now i have:
2002 Dodge Ram 1500 2wd
4.7
3.50 LSD
31" tires or 285/70/17

I tow a 5500 lb camper all over the country and i really need more power. It seems like i can never hit the HP that i want to because i cant get the truck up to the speed/rpm (70ish 2400/2500rmp) that has the HP. I can get to about 2100 rpms and then it downshifts HARD to 2nd to go faster. If i go downhill and get to 70mph with it then level out i can keep the RPMs up so i have the power. But if another hill comes up, My speed drops and there is no power and it downshifts hard to get up the hill. This is very hard on my tranny.

I think with the tires i have now i actually have about a 3.27 gear ratio and I know that doesn't help at all. And yes, i know i really need a Cummings to do the job but i don't have the money for that now.

So......I was thinking about gearing it lower (i think lower is actually a bigger #, but you know what i mean) maybe 3.90 or 4.?? to raise my rpms in 4th so i have the power. I don't know anything about this but to me it makes sense. Maybe i am way off.

I have a few of questions:
How do i find out what differential i have?
What is the lowest gear i can put in that diff? 3.9, 4.??
What is a good brand of gears and do i have to buy something else to keep my LSD?

I am sure i will have more questions, but this is getting kinda long. Thank you in advance for your answers.