Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - '08 Toyota 4Runner aero mods = 14% better fuel economy!

csnyder · 01-08-2019, 02:14 AM

You need to remember that 4 runner is a BRICK - both inweight and aero. Tuffer than nails, but not an economy machine. Even with the V6 it's thirsty.

That said, removing the rear spoiler will in all likelihood hurt mileage.
Removing the roof rails will help - particularly at over 60mph.
Getting your baseline on a 10 or 20 mile run going by fillup volume is a little better than guessing - - - -

Using cardboard and gaffer tape when anticipating wet weather is asking for trouble. CorPlast and tie wraps are MUCH better. Make a cardboard template taped up to hit all the gaps, then cut corplast to fit. Watch the gaps at the edges. Remember to leave access for the oil change!!!

Be REAL carefull about taping up air intakes. Try to take advantage of high pressure areas and smooth out the transitions to the rad with corplast baffles behind the grille. Make sure your belly pan does not restrict air exit from the engine compartment. An overheated engine or transmission will cost youmore than a lifetime of fuel savings.
Taping over body gaps will help. A stiff transparent tape like SlickStrip applied on the edge of the hood overlapping the fenders for instance, or on the door edge or fender bridging the gap (stuck to one part - doubled to provide a slide fit over the other) will do wonders on a lot of vehicles.
The 4 runner already has flush mount glass.

If you don't go offroading run it as low as possible. Is it a Limited with air ride?If so lowering is a cinch.

As noted by others, lowering your speed even 5mph will likely do more for your milage than all your modifications, and i've found a bit lower driving speed on a long trip doesn't change the overall travel time very much. You don't get as tired and stressed and you can stretch your fuel/rest stops a bit. Every extra minute in stops is a mile and a half you need to make up. Every 5 MPH is only 5 miles every 60. - an extra maybe 10 minutes per 100 miles at best.

Not sure how much good or harm removing the mud flaps will do - they clean up the air going over the tires and ARE relatively streamlined - particularly in comparison to the tire.

01-08-2019, 02:14 AM	#23 (permalink)
csnyder EcoModding Lurker Join Date: Jun 2012 Location: waterloo, Ontario Posts: 24 Thanks: 0 Thanked 4 Times in 4 Posts	4 runner aero mods You need to remember that 4 runner is a BRICK - both inweight and aero. Tuffer than nails, but not an economy machine. Even with the V6 it's thirsty. That said, removing the rear spoiler will in all likelihood hurt mileage. Removing the roof rails will help - particularly at over 60mph. Getting your baseline on a 10 or 20 mile run going by fillup volume is a little better than guessing - - - - Using cardboard and gaffer tape when anticipating wet weather is asking for trouble. CorPlast and tie wraps are MUCH better. Make a cardboard template taped up to hit all the gaps, then cut corplast to fit. Watch the gaps at the edges. Remember to leave access for the oil change!!! Be REAL carefull about taping up air intakes. Try to take advantage of high pressure areas and smooth out the transitions to the rad with corplast baffles behind the grille. Make sure your belly pan does not restrict air exit from the engine compartment. An overheated engine or transmission will cost youmore than a lifetime of fuel savings. Taping over body gaps will help. A stiff transparent tape like SlickStrip applied on the edge of the hood overlapping the fenders for instance, or on the door edge or fender bridging the gap (stuck to one part - doubled to provide a slide fit over the other) will do wonders on a lot of vehicles. The 4 runner already has flush mount glass. If you don't go offroading run it as low as possible. Is it a Limited with air ride?If so lowering is a cinch. As noted by others, lowering your speed even 5mph will likely do more for your milage than all your modifications, and i've found a bit lower driving speed on a long trip doesn't change the overall travel time very much. You don't get as tired and stressed and you can stretch your fuel/rest stops a bit. Every extra minute in stops is a mile and a half you need to make up. Every 5 MPH is only 5 miles every 60. - an extra maybe 10 minutes per 100 miles at best. Not sure how much good or harm removing the mud flaps will do - they clean up the air going over the tires and ARE relatively streamlined - particularly in comparison to the tire.