MPG with late Gen 2 Montero + larger tires?
- Thread starter All-Terrain
- Start date
SoCalMonty
Explorer
I'd run some toluene or e85 in with your fuel for a cleaner. They both clean things up pretty well, while raising your octane as well (toluene is 114, e85 is 106).
I'd run 30% toluene in a couple of my turbo cars back in the day...don't go more than that. I'd recommend the same with the e85.
I'd run 30% toluene in a couple of my turbo cars back in the day...don't go more than that. I'd recommend the same with the e85.
4D55 Performance
Explorer
Something seems to be a little off. I seems the truck needs a good overhaul. New sensors, plugs, wires, etc. Another critical item most overlooked are the injectors. They need to be rebuilt every couple hundred thousand miles and my guess is those are the original injectors in your truck.
All-Terrain
No Road Required
This truck has, as I read off the dealer's service records:
- New alternator
- New camshaft seals
- New front crankshaft seal
- New valve cover gaskets
- New spark plug wires
- New spark plugs
- New timing belt
- New air filter
All recent dealer-installed OEM parts.
I have a new front oxygen sensor on the way, and a new fuel filter in a box ready to put on.
- New alternator
- New camshaft seals
- New front crankshaft seal
- New valve cover gaskets
- New spark plug wires
- New spark plugs
- New timing belt
- New air filter
All recent dealer-installed OEM parts.
I have a new front oxygen sensor on the way, and a new fuel filter in a box ready to put on.
I always try and read these gas mileage threads since ill be getting a 3rd gen this late spring/early summer. Do higher speeds absolutely kill these vehicles mileage? My states interstate limit is 75. I always peg my cruise control at 80. Our excursion(bone stock v10) gets 11/12mpg on pure interstate driving @ 80 to 85mph.
SoCalMonty
Explorer
Yes, higher speeds absolutely destroy your gas mileage in pretty much any vehicle. I used to follow hypermiling websites and I've tried a LOT of the tricks. Out of every trick and part I tried, the biggest difference in fuel mileage was achieved by changing my driving style, and lowering my highway speed. This is echoed by most hypermilers.
The drag coefficient of the gen 1 and 2 Montero's is horrendous...something like 0.50 or above. Once you pass 60mph or so, the decline in fuel economy for every 5mph grows with each increment...it's not linear.
The difference between a tank at 60mph and a tank at 80mph is probably around 50 miles cruising distance, maybe more.
I still think the OP is pretty much in line with what he should be getting...he's basically getting the same number as the Mitsubishi and EPA estimates for his vehicle (15 combined). Seeing as how he notes a cruising speed of 75mph (or, about 15mph/20 percent higher than optimal for economy), I think that's fairly normal. His old Tacoma was also in range of the EPA numbers.
http://www.fueleconomy.gov/feg/Powe...997&make=Mitsubishi&model=Montero&srchtyp=ymm
http://www.fueleconomy.gov/feg/bymodel/1999_Toyota_Tacoma.shtml
Larger tires on flat roads while cruising at a steady speed might improve the mileage - but 31's were still a factory OEM size. That size is listed in my owner's manual for the optional tires as new.
You might be able to get a *little* better, but not much. Though, from having been through the "max mileage possible" thing on a few cars, I'm pretty confident that driving habits and speed will produce better results than cleaning your injectors or things of that nature.
Last edited:
4D55 Performance
Explorer
As with all vehicles, as they age and acquire miles, the MPG's will decrease. I have a 2009 Jetta Sportwagen TDI and I used to average 41-42 MPG combined when I bought the vehicle new 5 years ago, but these days I am lucky to get 35 MPG combined. The mileage has just slowly declined over the years but the car has 130K miles on it. It is just what happens to high mileage vehicles. I am sure my Jetta needs a tune up and the injectors need to be rebuilt. When I had my 2000 Montero with just 20K miles on it, it consistently got over 20 MPG's. I never have a tank get below 20 MPG's in the two years I owned it. It was basically a new vehicle because of it's super low miles. I did see up to 24mpg on the freeway with out even trying. Long story short, these vehicle are 15-20 years old and they show it. When working like new, 20+ mpg is realistic and is to be expected.
SoCalMonty
Explorer
If you guys haven't seen this yet, you might find it kinda cool. It's this hypermiler's project Civic, called the "Aerocivic." Here's a snippet from his website that demonstrates the effect of just 5mph has on fuel economy:
Link: http://aerocivic.com/
While it's ugly as sin...he's managed to get 95mpg out of a Honda Civic!
Link: http://aerocivic.com/
While it's ugly as sin...he's managed to get 95mpg out of a Honda Civic!
I did about 6000 miles on a recent road trip and here my observations. I have the same tires: 31x10.5x15 BFG TA KO, use 87 octane.
I get about 17mpg on the highway doing between 60-70mph, 16mpg on light offroad trails, and about 13-14mpg when doing inclines. What I noticed hurts the mpg the most is inclines on the highway. I try to keep the RPM at 3k and that gives me the best results. Regardless if its steep hills around the city, or steep inclines on the highway, whenever I go to 4k RPM or higher, my mpg suffers a lot!
I get about 17mpg on the highway doing between 60-70mph, 16mpg on light offroad trails, and about 13-14mpg when doing inclines. What I noticed hurts the mpg the most is inclines on the highway. I try to keep the RPM at 3k and that gives me the best results. Regardless if its steep hills around the city, or steep inclines on the highway, whenever I go to 4k RPM or higher, my mpg suffers a lot!
All-Terrain
No Road Required
Good info.
What is the year + model of your Montero?
Sounds like I'm probably where I should be, unfortunately.
jeep-N-montero
Expedition Leader
That's a good read.
I have a 1998 Montero (not sport).
MonteroLTD
Adventurer
On my recent 20,000KM trip, I averaged 18-20 mpg. Thats with a few hundreds pounds of gear, rooftop carrier, 265/75/16 a/t tires. City driving is roughly 14-15MPG.
scrubber3
Not really here
What about E85 would help the Montero get better gas mileage? How does it act as a cleaner?
On topic, be sure your tire pressure is good. Make sure your front end is tight. Keep up with your alignments. You'd be surprised how much better your mileage can be with a lined up set of wheels. Make sure the ignition system is good, clean the intake and injectors with a proper cleaning agent and technique.
Last edited:
jeep-N-montero
Expedition Leader
E85 is comprised of 85% ethanol(think alcohol) that cleans things out, you can put a little bit in mixed with regular gas but can't run straight E85 in vehicles not set up for it.