as i said im getting 30 with my 3 speed auto . but again its a 2 door not a 4 .

but i can say that i get  the best MPG  and power at over 3000 and under 4000
 thus this makes me feel that the engine  is set up  to run  the most efficiantly somewhere in that range

Yep, that's the power band. These engines love to rev a bit.

So how does the 4wd work in this, is it shift on the fly or do you have to stop before shifting into 4wd?

Also does someone make a reese hitch with a 2" receiver for the sidekick?

So how does the 4wd work in this, is it shift on the fly or do you have to stop before shifting into 4wd?

It depends.  If you have manual lockouts and have them locked in, then it is shift on the fly.  If you have auto hubs, then you have to come to a stop, before you can shift into 4wd.....unless you have shifted into 4wd previously and the hubs are still engaged, then you can shift on the fly.
Personally, I don't care for auto hubs and have swapped them out on both my sidekicks.

Also does someone make a reese hitch with a 2" receiver for the sidekick?

I have seen some with hitches....not sure who makes them though.  I made my own hitch for mine.

Calmini makes a class 1 hitch, but I think that might be to small for what  you want.  Most after market rear bumpers come with a 2" receiver installed.

Also does someone make a reese hitch with a 2" receiver for the sidekick?

Generally you have to have a bumper made, or buy one with a hitch in it.

there normal is one or two class 1  1/1/4  hitches on e-bay for sale . i believe they are 90 bucks or so . dont know that i have seen a 2 inch though

JC whitney has a 2" class 3 hitch for Trackicks.  Couldn't pull that much with one though, not enough torque.

The most it would pull would be a 5x7 trailer to pull mine and my sons atv's.