I have a v8 4000cc 2000 year.
Because this is Korea.
It costs about $ 1.5 a liter of gasoline.
Approximately ...
It can run about 124 miles for about $ 50.
It's the worst.

So naturally
I am looking for a way to improve fuel efficiency.
I think

Change the tires from 255.55.18 to 225.60.18,
Remove spare tires and 3 rows of seats

How much fuel economy will be improved.
Have any of you tested these tests?

 

You won't see much of a gain, these have never been fuel efficient vehicles. Your best bet is to do a full service on the engine and all fluids to make sure its running as smoothly as possible.

 

Or sell it. Seriously.

By the way welcome to the forum. We're mostly in the U.S. but members from the Middle East, the Caribbean, Africa, Central America, and oh yes Canada, have been on. Offroad France is an important contributor. I don't recall anyone from South Korea however so again, welcome.

 

Second the welcoming; always nice to get someone from outside the states

As for improving gas mileage, like ArmyRover said, so a full service. Also make sure your tires are fully inflated, makes a big difference, and minimize weight inside the truck.

I did find that converting to an electric radiator fan (see the post in my signature) gained me exactly one mile per US gallon. I've tried every trick in the book and it's literally the only thing I've seen any change at all from. I didn't even see much difference from the full exhaust change.

 

I removed my very heavy spare, got everything working perfectly (for about ten minutes. It is a Rover!), bought high octane octane marine gas (no ethanol), and removed the second row seats for two weeks. I saw one mpg difference, which is actually a big difference considering how bad I usually get. Smaller tires will help for slower driving. Alex's electric fan should help, too. The cone filter mod gives you the best airflow possible (and might improve mpg a little; I don't know).

I've had my truck since new and it never got decent mpg... but we didn't care back then because gas was so cheap! At the time high mpg was for weenies.

Depending on use case, I thinking the truck would be much lighter (and drastically less safe) with all five doors removed. They are HEAVY (especially the back door).

 

Speaking of... Been considering making up a full set of tube doors. Or getting a Jeep set and modifying them to fit. Either way, would be pretty neat. All 5 of course.

 

I know how to save up to 20% each week.
Don't drive 1 day.
��

 

I recently went with an electric fan, however I did not notice any mpg increase as I was so excited by the little bit of extra power I probably negated any mileage gains.

Seriously though, as mentioned, the highest octane fuel possible and the lightest foot on the pedal possible... drive like you have an egg between your foot and the pedal. Also on the highway cruise control helps keep it steady.

Best of luck!

 

Narrow tires and maybe a tad taller may benefit you some, you'll be a bit slower out of the hole (taking off)...but once you are at cruising speed...the engine should be turning lower rpms. Buying lighter rims, with flush faces would eliminate the egg-beater affect of a spoked wheels.

Read somewhere once...that for every 75 pounds removed from a vehicle...the increase in mileage is 2 tenths.

Welcome to the board.

Brian.