4x4 SUV Fuel Economy Ideas

[SupATro.0pA]

I'm in the process of getting a 4x4 SUV (1995 Isuzu Trooper) running well for the purposes of camping/overlanding/wheeling kind of adventures.

One of my desires is trying to figure out how to achieve optimal fuel economy while maintaining the 4x4 capabilities (essentially saving fuel on the road so you can burn it on the trail).

I'd like to discuss some of my thoughts at this point, create a thread on the topic (as I've found a few that bring it up but go nowhere), and share any mods with results.

Here's my current list of ideas:

• Manual Transmission
• Driving slower on the highway between destinations
• Getting thinner smaller off road tires (255/75/r16)
• Belly pans (that maybe double as skid plates)
• Easily removable or adjustable grille blocks
• Easily removable side skirts
• Easily removable air dam
• Kam back
• Water injection for highway speeds?
• Easily removable wheel covers
• Vacuum gauge

Has anybody else had success in this area?

[Stacygifford]

I love the trooper, and you have the right ideas.

Im not trying to be a downer or anything but that is definitely not the best starting vehicle, and is probably one of the most complicating use-cases for ecomodding. the ONLY thing that they really have in common is the benefits of engine tuning for low rpm efficiency (ie torque)

The belly pan acting as a skid plate can go a long ways, and could be very useful in both use cases. however, if it has a solid axle rear suspension (or front for that matter) , they would really be less than usefully for aerodynamic improvements .

I suspect a removable MASSIVE air dam and kam back would be the best starting points. if you built a off road bumper, you could even incorporate a few mounting points to make it super quick and easy.

I say go for it, and keep us posted!

[slowmover]

Records. (FUELLY app)

How long will you keep it?

How many miles will it cover in that interim?

What percent (of engine time) will be spent off-pavement?

Generally, the higher average mph, the better will be the average mpg. Learn to use those as tools to model driving behavior.

It’s all part of the total cost of ownership & operation. Use AAA or Edmunds to get a start. One needs to have all costs in view. You may not have depreciation costs, but your repairs and vehicle time out of service will be large).

Start there.

[oil pan 4]

Don't go smaller. Don't use A/T or mud tires if you can help it.
Use highway tires and snow chains. They will be the badest mud tires you will ever see.
Water injection does not appear to help gasoline engines, every test I have seen decreased fuel economy or did nothing.

[Stacygifford]

Welcome to the fourm BTW. Just saw this was your 1st post!

[SupATro.0pA]

Originally Posted by Stacygifford

I love the trooper, and you have the right ideas.

Im not trying to be a downer or anything but that is definitely not the best starting vehicle, and is probably one of the most complicating use-cases for ecomodding. the ONLY thing that they really have in common is the benefits of engine tuning for low rpm efficiency (ie torque)

The belly pan acting as a skid plate can go a long ways, and could be very useful in both use cases. however, if it has a solid axle rear suspension (or front for that matter) , they would really be less than usefully for aerodynamic improvements .

I suspect a removable MASSIVE air dam and kam back would be the best starting points. if you built a off road bumper, you could even incorporate a few mounting points to make it super quick and easy.

I say go for it, and keep us posted!

Yeah, this is definitely not what you would call a traditional Ecomodder build. I purchased the vehicle with passenger capacity, storage capacity, off road capability, and price in mind. The fuel mileage thing is a secondary goal.

Since I've got those lovely bell housings sitting as my lowest points, would a belly pan that sits flat below that overcome those axles? I'd still have a ton of space between the road and the belly pan.

[SupATro.0pA]

Originally Posted by slowmover

Records. (FUELLY app)

How long will you keep it?

How many miles will it cover in that interim?

What percent (of engine time) will be spent off-pavement?

Generally, the higher average mph, the better will be the average mpg. Learn to use those as tools to model driving behavior.

It’s all part of the total cost of ownership & operation. Use AAA or Edmunds to get a start. One needs to have all costs in view. You may not have depreciation costs, but your repairs and vehicle time out of service will be large).

Start there.

That app sounds fantastic!

It's not a primary vehicle, so I'll keep it as long as I want or can
(My vehicle philosophy is that it's better to have a few to divvy out the miles between, and a car with no payments is cheaper than a new car)

As to off pavement time, I'm not a hundred percent sure. I haven't had a chance to explore much off road yet. It's probably going to have more road miles at this point.

[SupATro.0pA]

Originally Posted by oil pan 4

Don't go smaller. Don't use A/T or mud tires if you can help it.
Use highway tires and snow chains. They will be the badest mud tires you will ever see.
Water injection does not appear to help gasoline engines, every test I have seen decreased fuel economy or did nothing.

I'm in SoCal, so I'm expecting more desert sand and rock than mud.

[SupATro.0pA]

Originally Posted by Stacygifford

Welcome to the fourm BTW. Just saw this was your 1st post!

Thanks!

I've pilfered knowledge in the past without contributing. Had a grille blocker for my matrix and solid hubcaps.

Did a long road trip in it a few years back where I was looking for non ethonal gas and driving slower. Hit 43mpg at one leg of that trip (which was crazy to me for that vehicle)

I'll probably share some posts with the Isuzu community as well, but thought this would be the better spot to record fuel mileage items.

[oil pan 4]

Snow chains, also great for sand.