350 mile tank in the Jeep Cherokee
 

Ok, not so monumental, but this is the longest trip I've been able to manage so far in this rig. The pump only put in 16.8, but the fuel light came on (comes on between 1/8 and 1/4 tank) a few miles before I stopped and I didn't want to push how far the Jeep would make it as there remained 80 miles in my trip. The trip averaged 23.8 and 24.8 mpg respectively each way, but with the in town driving and I think the pump registered more than it actually gave me as there was still at least two or three gallons in my tank. With the exception of this last tank, I haven't had to recalibrate the scangauge with each tank hardly at all so it's my belief that it's being genuinely accurate, just that last fillup threw me off.... by all rights (and with a few aeromods) I'll make that 30mpg highway yet! Next year I have to drive from WA to GA, so my goal is to mod this Jeep enough to make that drive at aforementioned mpg.

You can do it by slowing down. I've topped 165% of EPA highway mpg in all my cars on long highway trips. The AT Elantra is the toughest to achieve good mpg in.

You only have to top 158% of EPA highway mpg to get 30 mpg with your Jeep. 55 mph maximum speed for a tank of highway driving, and you should be there.

Miles per tank is largely irrelevant. I got over 600 miles on my last tank, but that doesn't mean I got good mileage. It just means I have a large tank.

If you can pull off mid 20's in a Cherokee, I'd say you are doing pretty good.

Never will understand mileage per tank.

I mean, you can get 100 gallon tanks for diesels...

Yeah, but miles per tank tells you how practical the vehicle is for long highway trips. If you're traveling 8 hours per day (at 60mph, that's 480 miles), it's convenient to only have to fill up once per day.

I'd probably not drive a Jeep if I drove 8 hours a day. ;)

As far as roadtrip vehicles, Jeeps (Grand Cherokees, and probably Cherokees too) are surprisingly comfy highway cruisers when running around 60mph. If 8 hours a day was a regular occurance, I'd agree that a more suitable vehicle would be in order.

Plus, on dead flat ground, holding 60mph even on the speedo, my instant mpg display (built-in, not totally accurate, but within +/- 1mpg usually) will read 27 mpg (no aero mods). And that's with the biggest V8 ever put in these things until the SRT8 came out... A smaller V8 or I6 should be able to get 28-30 instant in those conditions. It's the hills that kill the mileage on the highway.

I know my instant MPG display is frequently way off. But it is nice to have a ROUGH idea what to expect regardless. Comp, I love my ZJ as is, and rarely desire the V8 power. And yes, the 95 ZJ is a comfortable highway cruiser. But for longer distances and MPG, I take the Neon when I can.

I will agree that the 6 has adequate power for most situations. It's only when your really load it down that you say "Man I wish I had a V8". Once you've driven a V8, you start to appreciate it on short highway on ramps, or those stupid Merritt Parkway ramps with the stop sign at the top. With the 6, those can be a WOT experience almost every time. Not a big deal with the V8. Plus, the gas mileage is almost the same, so I figured I'd get the V8. Then, when I retire it from DD duty in a few years, I can have some fun with it (thinking of stroking the 360 to a 408 with twin turbos).

None of my friends with 5.2 ZJs get close to my mileage no matter how they try. But yes, when loaded, I wish for a bit more power. When I once towed a Cherokee on a tow dolly 160 miles, it wasn't so much the power I wanted as much as I needed a lot more BRAKE! Though I have considered a turbo at 5 psi...

Ironically, the one guy I know with the 5.9 gets better mileage than the 5.2 guys do.