Jeep Tuner Help Needed

I have been messing with a couple of Jeep Grand Cherokee's for a year or so. They fit my needs pretty well, can haul 5 people easily, 4WD for the winter, can tow 4,000lbs and parts are cheap. Only kinda gripe is getting 17mpg-18mpg in combined driving. I have heard good things about several of the tuners on the market, SuperChips Hypertech etc. They claim various options, economy setting with 1mpg-3mpg increase and tow and performance settings. I am ignorant about them in general just looking for any tips. They all run about $300-$325. Just looking for suggestions or 1st hand experiences. Thanks

BBC

Sorry, I don't have any experience with those tuners. But years ago 4Wheeler or JP magazine took a high-ish mileage XJ Cherokee and wanted to see if they could get better economy. IIRC, they replaced the air filter with a K&N unit, and changed ALL the gearbox fluids with synthetic fluids. I want to say they picked up more then the 1-3, but not a lot more. Maybe 4-8 mpg? Maybe do those changes and decide on a tuner and you can flirt with 20 mpg??

i have a friend at superchips. i will ask him for some info.

What year? SCT works, lots of canned tunes available for those. Scope out www.jeepgarage.org for more info, lots of WJ/WK and ZJ sprinkled in.

My 4.7 V8 '99 Limited got about 22mpg highway with a clogged cat. 19mpg combined. I was not nice with the happy pedal.

In reply to Dr. Boost Angry Corvair and beans;

Thanks for the replies guys. I am getting a K&N just haven't done it yet, waiting for some stuff to sell on eBay 1st. Angry, would love to hear what your friend says. beans 19 with the 4.7? wow that is great.

BBC