Another MPG Thread (1 Viewer)

[100d ua]

Hear me out, though... 2000 LC with the 4 speed transmission. I am not here to complain about MPG but more wondering if this is about right based on others experience.

I am consistently getting 10 MPGs, lucky to hit 250 miles before the gas light comes on. My commute is ALL freeway, 40 miles round-trip, some side roads...

3" lift, front metal bumper, 265/75r16's KO2's, all fluids routinely changed and fresh. Current mileage @ 250k.

Factors that I think MAY be contributing to this MPG:
-75-80 MPH freeway commute (3k RPM?)
-Fuel filter last changed 100k miles ago
-Possible poor alignment?
-Exhaust header leak (does that even make an impact?)

I'm about to install ditch lights and sliders, would hate to be in the single digit MPG range, if so, woulda got a Hummer LOL.

Current setup for reference:

Any thoughts?

 

[ramangain]

That front bumper and highway speed aren't doing you any favors.

What do STFT and LTFT say?

 

[BullElk]

That 80 mph deal is a definite mpg killer.

 

[100d ua]

That 80 mph deal is a definite mpg killer.

I'm doing a test now... staying in the right lane @ 60-70 mph to see if there is a significant change.

 

[BullElk]

I tested it at 65 once upon a time and saw like 1.5-2 mpg difference if I remember correctly. Of course, in the South, as I am, the A/C is also a significant factor.

 

[100d ua]

That front bumper and highway speed aren't doing you any favors.

What do STFT and LTFT say?

Scangauge?

 

[pjess50]

I'm doing a test now... staying in the right lane @ 60-70 mph to see if there is a significant change.

This will make an obvious difference... I've done the same with my 98 LC.

 

[medtro]

Do you have skid plates?

 

[100d ua]

Do you have skid plates?

Just the OE ones.

 

[medtro]

Just the OE ones.

That's good. I read someone got their MPG back after reinstalling OEM skid plates.

 

[Bisho]

Your lift and bumper kill what little aerodynamics the truck has.

However, for reference, I have a 1.5” lift and the same bumper. I’ll get 14mpg very reliably, whether I’m around town or doing 75-80 on a road trip. Manually calculated. I run the power switch engaged all the time. I found I got better mileage and much prefer the shift profile.

How aggressively you work the accelerator can also have a big impact.

 

[J1000]

Exhaust header leak yes makes a difference, probably one of the biggest after cruising speed. There was a reason the speed limits were all 55mph during the gas crisis.

 

[KraziAzn]

jesus 75 to 80? Yeah 10 mpg sounds about right. I cruise around 62mph RPM 2k-ish just to get 13mpg

 

[OEMGUY0720]

I'm doing a test now... staying in the right lane @ 60-70 mph to see if there is a significant change.

That’s the sweet spot right there

 

[100d ua]

Successfully made it into work today driving 65-70 LOL... I don’t have any inherent rush to get to work or back home I just blame it on BMW habits.
I’ll report back my findings after the week of soft feathering the throttle lol.

 

[Zjohnsonua]

The single biggest fuel sucker there is speed. Drag and the power to overcome are exponentials of a given velocity. Slow down a bit, make sure that your plugs and O2s aren't outside their service life, and check your tire pressures. Outside of that, enjoy those exquisite 12-14 mpgs.

 

[David*BJ70]

I don't understand why people driving «so» fast ! Well, I'm not the mother of anyone but speed is just a way to decrease everfything, from MPG to safety. It is not because you can that you have to drive fast.

My 100 is a diesel HDJ100 and weight 7300lbs. I rarely drive over 60mph and try to stick at 2000-2100 rpm. My average from the last 21 000 miles is 13.4L/100km - 17.6us mpg.

I'm not trying to compare «my» apple with «your» orange, still, speed and RPM play a lot in MPG...

 

[Escape Artist]

Just curious what air pressure you're running in the tires? If I accelerate very, very slowly and really milk with throttle driving 62 mph (1900 RPM) I'm getting almost 19 miles per gallon on the freeway over a thousand mile road trip. I have an 06 lc with the five speed and VVTI. I made a gas mileage thread about it, getting 500 miles to the tank with photos. I'm going up a size and tires and possibly reguring, adding lockers and bumpers. It'll be interesting to see what the gas mileage hit is going to be. If I drive 80 miles an hour I'm getting right around 12 and a half miles a gallon ... Just for reference.

 

[krispykritter]

Mine is an 06 with 33 inch tires on 18 inch wheels, about 1.5 inches lift, rock rails, stock bumpers, and a hidden winch. With my normal load of me and probably about 100 lbs of stuff, I get reliably 14 to 15 mpg on the highway at 75 mph. I do have the 5 speed transmission and turn around 2300 rpm at 75 mph. I also have a slight exhaust leak/header tap, mostly when starting and cold, goes away when warm. I run 40 psi in my tires.

Around town I can't really get above 9-10 mpg. My daily commute is so short that I never really get up to operating temp and I have a bunch of stops between home and work.

10 mpg seems rather low, though if I tried to do 80 I imagine I'd drop from 14.5 to 13.5 or so. Even so, that seems worse than it should be. Time for new oxygen sensors maybe?

 

[Bisho]

BTW, I did see a slight bump in mpg (.3 or so) after I changed all my dif fluids to Mobil 1 synthetic.