Well, it's not a chip, it's a tuner or programmer. Hypertech 52001 is the one that works with the 3.7.
Usually it's $379, but you can find it cheaper on sale at times.

Hypertech 52001

Here is one on craigslist (in Canada), for $150. Just make sure it's unlocked if you guys buy a used one.
Used 52001 on CL (Canada)

Here is one on craigslist (in Tennesee), for $175, shipped.
Used 52001 on CL (Tennessee)

 

For some reason, the 52001 does not support the 05-06 3.7L. It starts with 07...

 

ok, that sucks. Mine's an 05 and I'm definitely interested.

 

The 52501 DOES support your year. The 52501 must superceed the 52001 part number.

 

so those craiglist ones wont work on an 06?

 

are they easy to use, never used one of these before? Do you need a computer to run it like a PC ?

 

I'm guessing no, that blows for sure.

 

I'm seeing the 52501 model as 2007-2010 for the 3.7 also.
And 2005-2010 for the 4.7.

 

Hmm, I went to hypertech's website, plugged in my truck (06 dak 3.7L) and that is the "max energy" part number that came up.

 

The only thing that you need your PC for is to activate it and update it for the 3rd gen Dakota, if that's what you got. I got one but I'm still tryin to find out the right settings for it, cause of right now I can't tell any difference for the price that it is