If that truck has the 5.9 in it you will get lousy mpg's.

 

Is it a 4.7 or 5.9? The 5.9 is a thirsty engine, but has a lot of power potential, intake, exhaust, and a tuner will really awaken the beast.

 

That's good to start with but can you say "stroker kit?"

 

Hell yeah, but that gets into money

 

What are the problems with the stock limited slip differentials?

 

They've gotten a reputation for disintegrating because of a metal clip coming loose and grinding the the differential apart. It does happen, but it's not so common that everyone with a stock LSD needs to run out and replace theirs.

 

Its a 5.9. Is the 5.7 Hemi that much better on mpg??

 

Yes. The 5.9L has much worse fuel economy than the 5.7L Hemi, and less power to boot. There are a lot of stock Hemi Quadcabs getting 20mpg highway, the 5.9L in the same truck will average 15, maybe 16mpg highway. And in town, if you have a heavy foot it's not hard to put the 5.9's mpg into the single digits.

 

There is a big difference when it comes to MPGs between the 5.9L magnum and the 5.7L Hemi. My previous 2001 was getting between 9-12 mpg depending on where I was driving. I could barely get about 250 miles to a 26 gallon tank, it sucked. The hemi I'm driving now has added an entirely different bonus I wasn't expecting besides power, and that's gas mileage. I'm getting 17-18 mpg in the city, and around 20 on the highway. I've yet to track how many miles I can get with a full tank of fuel (probably because I'm too cheap to fill it up all the way), but the truck can easily drive around for a day and not drain the tank. The hemi is big upgrade to the magnum.

 

Wow, I only get about 10.5 in my 5.7. And thats after I put 10 more pounds of air in the tires.