I have an 06 ram 2500 4x4 with the 5.7 hemi with a auto trans. I am looking for some ways to improve the pulling of my trailer(27' 5 th wheel alum 3 horse)Will the cold air intake help?,or a thottle body spacer? or both? I need more power down low in rpm range (1700-2000 rpm) Am running at this rpm when under load at hwy speeds. The truck will pull at 1900 rpm (This is top gear conv. locked up) but as soon as you hit alittle rise it drops a gear and is back at 2500 rpm.

 

The CAI won't help you much unless you have other mods like exhaust, headers, etc. Your best bet would be a tuner, you can mess with the rev limiter and even play around with your shift points. It's prolly the best bang for your buck mod for a stock engine.

 

I'm assuming you have stock 3.73 gears, which are fine for the low end grunt of a diesel, but woefully inefficient for the Hemi pulling a load. IMO they should only offer the gasser 3/4 tons with the 4.10s.
Your best bet is to regear to 4.56 gears, it will ease the load on your transmission by keeping you up in the power ban more efficiently as well as getting your RPMs up around 2100-2500 on the highway, which is more in the Hemi's sweet spot.

Anything else, bolt on wise will not give enough improvement to justify their cost for your purpose...

 

I have the 5.9 gasser in my 02 and pull a 26.5 foot 5th wheel it goes ok but it sure could use some more in the low end as well... I put the K&N CAI and t-spacer on mine and it is a little better but not enough to justify the $$$
Go with a chip and CAI then exhaust work...(in my opinion)
At least you have a newer one with the hemi... What are the chip options for a 02 360???