"Chasing MPG in my 80 series Lx450" How I increased my gas mileage.

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Well, 10mpg makes the math SUPER EASY once you realize you're carrying 25.5gal total and the little orange light comes on when you have about 5 gallons left in the tank - time to stop for gas!

I took an 1800mi road trip last summer across several deserts from AZ, NM, CO, NB, SD, and my biggest problem was hearing protection from hours upon hours of gear whine. Plenty of places to stop for gas.

Didja know; two foam ear plugs fit perfectly in the center vent slots for easy access!
 
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About the only thing you can do is properly baseline the truck, making sure the vacuum, fuel, exhaust and intake systems are fully intact. Then, you'd have to return the truck to stock tire sizes and gearing, reduce the lift and remove any of the stuff you might have bolted to the exterior. Even then, you'd only get back to 15mpg on the highway and this may impact the way you use the truck -- although probably less than you might think.

I have a fully baselined engine with 250k miles and stock tires with a (maybe) 1.5" lift. I have drawers and a fridge in the rear and carry some tools. I can still get over 15 mpg on highway trips where the speeds stay below 70mph, but once I start going 75+, I drop down to 13 mpg or so, this is all mostly with the A/C on, but I don't notice a lot of difference in the winter when I am not running A/C.

It is becoming less and less practical to use these vehicles for longer commutes due to the cost and need for parts due to their age. I highly recommend a fuel efficient commuter car if you are putting a lot of miles on your 80.
 
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Well, 10mpg makes the math SUPER EASY once you realize you're carrying 25.5gal total and the little orange light comes on when you have about 5 gallons left in the tank - time to stop for gas!

I took an 1800mi road trip last summer across several deserts from AZ, NM, CO, NB, SD, and my biggest problem was hearing protection from hours upon hours of gear whine. Plenty of places to stop for gas.

Didja know; two foam ear plugs fit perfectly in the center vent slots for easy access!


Gear whine can occur with any fear that's improperly installed. My Yukon's sound stock.
 
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You must be an anomaly with the Yukon's. I've run several sets including the ones in my 700hp truck.

I have had a ton of friends run them. They're usually a quality product.

Yukon gears are like BFG tires for me. Everyone else seems to like them, I keep getting the s***e end of performance from them. This is the second set the shop tried and they still whine like a banshee at anything over 45mph.
 
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Yukon gears are like BFG tires for me. Everyone else seems to like them, I keep getting the s***e end of performance from them. This is the second set the shop tried and they still whine like a banshee at anything over 45mph.

I don't doubt your experience.
 
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I don't doubt your experience.
Yeah, disappointing though since this was a shop that's been in business for years with good reputation. My Jeep is still running great from a gear and locker install they did back in '01. Gonna give Nitro gears a shot next.
 

mudgudgeon

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COYS

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Well, s***. So what's the alternative gear set brand?

The gears, whether Yukon gold or Nitro charged, are only as good as the installer. I’ve had my Nitro 4.88s 50K+ miles zero issues and I’m a stickler for oddball noises.

The most effective way to increase your fuel efficiency is with your right foot. Speed kills mpg. I recall that an increase of a mere 5mph from 65 to 70 can reduce your car's efficiency by 2x. You wanna get there quicker? $uck more gas. As I had stated, there is no free lunch.

My ‘97 with a 9k mile new 1FZ-FE long block (nothing reused except the valve cover) + manifold to exhaust tip fully new OEM system, nets about 12-3mpg city/fwy and maybe 14mpg at 75-80mph avg road trip mode. I'm sure I can do better, but traveling at 65mph on I-5 in the middle of CA having semis try to pass me ain't worth the squeeze.

I'm at about 105lbs per corner running 37x12.5R17 BFG KM3s. Stocky body.
 
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clx16

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you are running 105psi in your tires? Must rattle your teeth out
Can you imagine the contact patch size? Don't try to stop too fast!

Although i don't think it is about Psi but tire weight.
 

COYS

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Can you imagine the contact patch size? Don't try to stop too fast!

Although i don't think it is about Psi but tire weight.

Because, you know, who weighs their wheel/tire combo because that's not an important piece of data. Cuz, you know x2, all tires and wheels weigh about the same so long as same general dia/width. lol
 

GW Nugget

Do the best you can with what you have...
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All great comments & opinions, thank you for you time...
Like some have wrote I could buy a 45mpg car or motorcycle or ever one up to riding a bicycle, but remember I wrote this is a GAME called casing MPG. It's just a game.
According to the link below on 97LCs MPG is 12 city/14 highway so I am ahead of the game so far with 37s , low gears, dual batts, winch & amour.
Currently reading 15.1 mpg with 248.5 on my Ultra Gauge & 249.8 on the trip meter with just under 1/4 tank left hoping to breach the 300 mile threshold.
Add to note: I added a % of throttle position in the lower left of the UG. It reads 15.3% at 55 mph & idles at 10% open. This is for @ToyotaDon :steer::smokin:
I could put bigger tires back on to get the RPMs down, my 38 Patagonia's had less rolling resistance then these Mud Hogs...
Havin fun with the Lx and I'm out...

https://www.fueleconomy.gov/feg/Find.do?action=sbs&id=13977
20220724_162147.jpg


Happy Trails...

 
Last edited:
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All great comments & opinions, thank you for you time...
Like some have wrote I could buy a 45mpg car or motorcycle or ever one up to riding a bicycle, but remember I wrote this is a GAME called casing MPG. It's just a game.
According to the link below on 97LCs MPG is 12 city/14 highway so I am ahead of the game so far with 37s , low gears, dual batts, winch & amour.
Currently reading 15.1 mpg with 248.5 on my Ultra Gauge & 249.8 on the odometer with just under 1/4 tank left hoping to breach the 300 mile threshold.
Add to note: I added a % of throttle position in the lower left of the UG. It reads 15.3% at 55 mph & idles at 10% open. This is for @ToyotaDon :steer::smokin:
I could put bigger tires back on to get the RPMs down, my 38 Patagonia's had less rolling resistance then these Mud Hogs...
Havin fun with the Lx and I'm out...

https://www.fueleconomy.gov/feg/Find.do?action=sbs&id=13977
View attachment 3068114

Happy Trails...



You should build a spreadsheet. Enter your trip meter and have it correct for the tires. Use that mileage to hand calculate fuel. I bet that scan gauge is off. You can use the spreadsheet also to compare each tank to the scan gauge to give you a running tally of it's error.

I've done this in the past with oem dash meters. It's surprising.
 
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Here's an example

Its the one i use. My km's and trip meter are corrected for my tires before calculating mpg's

I am a poor with a 91 and a diesel so I don't have a fancy scan gauge but adding the comparison is simple.

spreadsheet.jpg
 

Broski

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Here's an example

Its the one i use. My km's and trip meter are corrected for my tires before calculating mpg's

I am a poor with a 91 and a diesel so I don't have a fancy scan gauge but adding the comparison is simple.

View attachment 3068227
This is the proper way to calculate fuel mileage !!

Well done ;)
 

GW Nugget

Do the best you can with what you have...
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You should build a spreadsheet. Enter your trip meter and have it correct for the tires. Use that mileage to hand calculate fuel. I bet that scan gauge is off. You can use the spreadsheet also to compare each tank to the scan gauge to give you a running tally of it's error.

I've done this in the past with oem dash meters. It's surprising.
I did calibrate the UG on a 100 mile trip on google maps, was off .5% See the trip verses the UG of 249.8-248.5=1.3 miles that's .521% over.
I wrote I was .5% over in the 1st post.
So do I qualify? :meh:
~~~~~~~
According to you chart, you drive a lot, I don't.
It takes me about 1.5 to 2 months to go through a tank off gas, this is why I can afford to daily my adventure rig.
10.5 miles per round trip X 14 trips per month that I work (12hr shifts)
10.5 X 14 = 147 miles per month.
I can keep doing the math, but that would be boring, but since I'm board, I will bore you on...
At 10 miles per gallon its 200 miles per tank. At 15 miles per gallon its 300 miles per tank.
147x2=294 miles equals 2 months per tank.
My UG is set up for 20 gallons per fill up. My DTE is amazingly close to when the gas light starts to glow.
Lets not get into the price per mile crap. (My gas is $6.40 per right now)
I'm just wanting better mileage & I have achieved from 10 to over 14 so far & have more to come, but takes time.
Remember its a game.
 
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I did calibrate the UG on a 100 mile trip on google, was off .5% See the trip verses the UG of 249.8-248.5=1.3 miles that's .521% over.
I wrote I was .5% over in the 1st post.
So do I qualify yet? :meh:
~~~~~~~
According to you chart, you drive a lot, I don't.
It takes me about 1.5 to 2 months to go through a tank off gas, this is why I can afford to daily my adventure rig.
10.5 miles per round trip X 14 trips per month that I work (12hr shifts)
10.5 X 14 = 147 miles per month.
I can keep doing the math, but that would be boring, but since I'm board, I will bore you on...
At 10 miles per gallon its 200 miles per tank. At 15 miles per gallon its 300 miles per tank.
147x2=294 miles equals 2 months per tank.
My UG is set up for 20 gallons per fill up. My DTE is amazingly close to when the gas light starts to glow.
Lets not get into the price per mile crap. I'm just wanting better mileage & I have achieved from 10 to over 14 so far & have more to come, but takes time.
Remember its a game.


As it's simply a gauge and an estimate, that's why I suggested you verify with hand calculations.

Claiming a gain based on a gauge that's estimating fuel consumption is a game with no verifiable results. You have no actual proof other than hoping your gauge hasn't faltered. I was simply trying to help you prove gains.


I do drive a lot. I can also afford to drive my adventure rig daily.

48 miles round trip for work plus all my other driving.

The price per mile is because I wanted to see how much the continued rising fuel costs were effecting me. It's a calculation that took 3 seconds to add to an existing spread sheet.
 

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