I am going to buy a used H3 in the next month or two. Is there a year that is better than any other? Are there inexpensive add ons to squeeze some more power and fuel mileage out of the 2006 or 07's? I have a heavy stock trailer I pull now and then too how is there brakes? Thank-you

 

i guess you wont find an add on that boosts power in a noticeable way.
if it did it would cut your mileage.

the KnN filter adds a few hp at 4000 rpm,where we dont spend time, at great,unrecoverable expense.

you might want to start your h3 life with an h3 equipted with a tow package and drive it for a few weeks b4 making changes ,or jumping to conclusions about lack of power.

i drive to Pa. up steep hills and when i push the gas my 07h3 3.7,,,GOES FASTER!!!

have fun

tom

 

I'll echo whta drtom said: make sure your H3 already has the tow package. The OEM Hummer H3 tow bar is not that easy to find aftermaket.

 

By the way the H3 brakes are oversized and more than adequate for towing. Keep in mind that the towing capacity is greter with the H3 Alpha (v8) vs. the H3 base model with the 3.7 liter engine.