Buy a used, well maintained Audi or Subaru for your long travel. Keep the Disco as a project truck. I have a few Audis. One is a 2004 A4 Ultrasport with 250k miles. Runs like new and gets 30-32mpg on long trips. Beats the Disco's ass, along with every other 4wd truck, in the snow as well. Good luck!

Ah, guys, killing me with the practicality. Brian, thanks for the tip on Trailhead. I thought they were further west. Might see if I can plan a visit one day. Wonder if they've got an LS D2 I could test drive....

In my Disco, aot of those coasting issues went away when I made the motor breathe better. Headers, intake, cam, port and polish. It coasted almost as well as my Silverado, and in neutral she felt just the same. I don't think there's an 8nherent problem with the drivetrain, but if that turns out to be the case I'll soon have a match set of Dana 44 front/Crystlwr 8.25 rear that I could swap in. Might anyway if the engine swap destroys the stock axles too easily. I just love the stock wheels is my only issue with axle swaps...

As for vehicle systems, the only concern is the BCU which seems to be happy enough in ShadeTree's LS swap. I'm building on some of his work for my planning. I'm not super concerned about systems interfacing as long as I can get a. Standalone ECU for the engine.

TD5 swap is an option, and I could get a manual with that. It would all botm right in which is nice. I could look and see what exactly is required worth that. 30 mpg though? I find that hard to believe. I was thinking they got low 20s as well. I could be wrong though.

I appreciate everyone trying to bring me back to reality, but let's continue on this train a while as if my mind is set. It's not and I'm still considering other options, but let's have the discussion as though it is.

I really appreciate everyone's insight. The cumulative knowledge on this forum is truly immense.

I should also note, this move is probably almost a year away, so I've got some time to do whatever I decide. This isn't something that needs to be cobbled together in a couple months.

I'm closing in on 1,000 miles with the 5.3 LS now. Last mpg average on a highway trip (rough calculations) was around 18 on regular gas with oversized tires. With stock tires and a better tune (still working out bugs), I'm sure I'd be get a little more mpg out of it.

It all depends two things: how much of the Rover do you want to retain and budget.
I went with the 5.3 because it was cheap, easy to find, and roughly the same physical size as the Rover V8. I kept the ZF because it was working just fine and I wanted to keep the overall cost less than $5k.

If I was going all out for mpg, I'd go with the GM LV3 V6 4.3. Slightly less power than 5.3, but a V6 with all modern parts. I don't know if it would get 22 mpg; the limiting factor here is aerodynamics, but it'd be about as close as you'd get right now with a gas engine. Getting the Rover electrical to work with that setup however is another conversation entirely.

X1 ................... too true, 29-30 mpg is easily achievable at 70-80mph on autoroutes. 150K miles and in 15 years the engine has NEVER caused a moments trouble yet including ALL the attached ancilliaries. (tempting fate if you believe or are superstitious, I'm not)

If you're considering an ecoboost, look for a wrecked stick shift Mustang with the 2.3l ecoboost 4 cylinder. Probably a few of them around. 310HP and 30mpg in the 1,000 lb lighter Mustang. Probably would get about 23mpg like the 4x4 Explorers. My sister in law has a 2 wheel drive 4 cylinder ecoboost Explorer and just got 26mpg on a trip to Florida. The 2 wheel drive is about the same weight as the D2. 4x4 Explorer is a little heavier.

Yeah, if you're considering a raw build...the sky is the limits. 4.3 is a great engine, had one in my Jimmy...put 300K+ on it...without any issues. I'm not sure what the horsepower was, but it would be comparable.

​​​​​​​ Brian.

AC, tell me more. What computer is running your engine? The Rover ECU or a Chevy one? I'd more heavily consider an LS family engine if it could get me closer to 20. The savings on the front would roughly balance out the cost in gas. I'm gonna probably ditch the ZF either way in favor of a manual which will save some on gas. In the way of electronics, I'm ready to ditch everything but the BCM.

Are we talking US gallons or European gallons? One Euro gallon is 1.2 US gallons. If we're talking Euro gallons, that gets us closer to 23-24 which would still hit the mark.