2005 Towing capacity confusion

So I am looking to tow about a #4200 trailer with my 2005 X with the 4.0 liter and it has the 3.55 gears. As I see on the site it is atleast #700 pounds over what the X is rated for. As far as the weight goes it will be a horse trailer (#2300 Est.) One horse at about (#1100 Est.) and a second horse at about (#800. Est.) I have a tow package and the class II hitch already. But from what I have read you have to have lower gearing and a class III hitch to get the max tow rating out of it? Can I do a gear swap? What would I have to do in order to do it? Would it affect the advancetrac? Also I was considering using a set of lowering springs. Anyone have an experience as far as towing with a lowered X? I am on the fence as to whether or not I should just trade it in for a truck or Full size Suv. This will be done on a regular basis not just a one time thing either. And obviously my X was not free and I don't want to tear it up. Anyway sorry for the long post and I appreciate any and all advice, suggestions, and/or comments. Thanks guys and sorry for the long post

 

[MountaineerGreen]

Some good reading here for starters-

http://www.explorerforum.com/forums//showthread.php?t=208532

 

[bumpinkicker04]

Some good reading here for starters-

http://www.explorerforum.com/forums//showthread.php?t=208532

That seems like a pain in the A** and a little more money than I want to spend. I think I might be getting a new truck after all. It seems like it would be alot less headache in the end. Darn I always hate having to buy new cars

 

[MountaineerGreen]

Yup... It's a common thing here these days- under equipped Explorers and people wanting to tow with them.

 

[jlseadoorxp]

You guys are making too big of a deal of a lousy 5% axle change. I basically took my 2005 4.0 liter XLT and only added a class III / IV hitch and I tow a loaded 228 mako which is nearly 6,000 lbs with the trailer and except for a few steep ramps, I rarely have any trouble. The axle change from 3.55 to 3.73 you won't notice at all. I also leave my OD off and drive sensible when towing and change my transmission fluid every 30,000 miles. IMHO, spending $1500+ for an axle - speedometer - CPU calibration change is a complete waste of money.

 

[jlseadoorxp]

And if I lived in a hilly region of the country needing more grunt , I would consider moving up to an Expedition before messing with an axle change or a 4x4.