"Chasing MPG in my 80 series Lx450" How I increased my gas mileage. (1 Viewer)

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87 Octane on next fill up it is...
 
I'm open to suggestion.
I can route the PCV hose in front of the throttle body (throttle plate). I would need to Tee into the same hose as the current air vent which in my mind is sucking gases out of the crankcase when the engine is running. I just want to keep a OE factory look on the PCV hose to keep the smog guy happy.
As far as Don being a good friend I don't know if you are messing with me on the throttle plate statement???

Yes, the throttle comment was made "tongue in cheek" as I think everyone knows acceleration uses more fuel.

I'm not opposed to using catch cans, but knowing the evolution of crankcase ventilation systems, the idea was implemented before emissions were a concern. The Positive Crankcase Ventilation system relies on those pressure differentials I mentioned previously. Eliminating that connection almost inevitably will lead to increased crankcase pressure.
 
"In my town 87 to 89 octane is 10 cents per gallon, that's $2.20 per tank."

First time I read that line I immediately looked at where the poster is located. Last time I saw local gasoline prices anywhere close to that was in Iraq almost 20 years ago. I had to reread that post a couple of times and the other posts for context then it made sense.
 
"In my town 87 to 89 octane is 10 cents per gallon, that's $2.20 per tank."

First time I read that line I immediately looked at where the poster is located. Last time I saw local gasoline prices anywhere close to that was in Iraq almost 20 years ago. I had to reread that post a couple of times and the other posts for context then it made sense.
Fixed it... is this better?
In my town from 87 to 89 octane, there is 10 cent difference per gallon, that's $2.20 per tank. (To me that's not a big deal.)
 
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Hah, I did a double take on that post as well.

I always go 87, but the same concept applies when you overthink a 1/2mpg difference on a tank. Even 1mpg, even at these prices, is not a lot. Drink one less beer and you’re good.
 
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Hah, I did a double take on that post as well.

I always go 87, but the same concept applies when you overthink a 1/2mpg difference on a tank. Even 1mpg, even at these prices, is not a lot. Drink one less beer and you’re good.

1 mpg at 12 to 13 mpg is $8 per tank. Depending on how much you drive that can add up.

I drive enough that it would equate to $48 a month.
 
True. I guess I don’t drive a ton, about 10-12k annually.

However, I have to think that if you own an 80, $50 a month isn’t a huge concern 😜 but on top of everything else increasing, it certainly adds up.
 
True. I guess I don’t drive a ton, about 10-12k annually.

However, I have to think that if you own an 80, $50 a month isn’t a huge concern 😜 but on top of everything else increasing, it certainly adds up.

You can buy an 80 for 4 or 5k. Not everyone with an 80 is rolling in money.

We've had college kids on here discussing driving theirs daily. I bet $50 is a lot.
 
You can buy an 80 for 4 or 5k. Not everyone with an 80 is rolling in money.

We've had college kids on here discussing driving theirs daily. I bet $50 is a lot.
As a college kid I can attest, if I drove my cruiser to work and school this year I'd be paying almost $400 a month, assuming gas doesn't get any higher than it is.
 
I'm currently seeing 16 mpg (freewayin my '97...BUT, she's wholly stock and on 265/70r16 tires and running (*GASP*) 87 octane fuel with no 3rd party additives.
I live in Vancouver, WA and commute 30 miles to Hillsboro, OR...AT MOST, 5 miles total isn't highway.
A LONG time ago I read multiple posts (before I had a MUD login) that 64 mph was the "sweet spot" for this engine and fuel consumption on the freeway so I try to stick to that speed, which always confused me because lower speed = lower RPMS which = better fuel consumption...but I literally saw more fuel use running the freeway at 55 mph than at 64 mph, so, I stick to that. I also run the CC as soon as I'm up to speed - I also use it to decelerate, saving wear and tear on my brakes.

With the AC on (but not using recirculate), I see about 14 MPG on the freeway.


She's stock, as mentioned, and is in the process of being baselined and then built over the next couple of years as a camping rig so I know my MPG will drop as soon as I add on bigger tires, lift, front/rear bumpers, swing out tire carrier, roof rack, and cargo drawer system.
 
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If you've advanced timing you likely need higher octane. But at what cost of power?
You're spending more money for what, 10hp? Maybe.
This is similar to my industry when people tell me they overclocked their processor prior to them being built with HEAVY gaming in mind...and I'd simply ask, "Why? You're burning up your processor faster by getting minimal gains out of an already stressed gaming rig"

The ROI isn't enough for me, I guess.
 
Gary I really think what's killing the gas mileage is the steel beadlocks and 37" tires. Probably 1.5 to 2 or more miles per gallon.
You said your self that for the last few years your just using it to commute to work.
I know it won't look as cool but just put you stock wheel & tires back on for now:meh:
 
Gary I really think what's killing the gas mileage is the steel beadlocks and 37" tires. Probably 1.5 to 2 or more miles per gallon.
You said your self that for the last few years your just using it to commute to work.
I know it won't look as cool but just put you stock wheel & tires back on for now:meh:
When I bought my new 265's everyone around me laughed...And I know...265's are small tires compared to the 35's, 37's, and even larger (in some cases) that other Cruiser owners put under their rig. But for me, personally, why put a 50 pound anchor on each corner while I'm baselining her and not taking her out on trails yet? So, I went with the smaller/lighter tires (Cooper Adventurer 265/70r16)...the only reason I even put new tires on was because the old ones were so bad they were dangerous. I'm planning on new tires and the lift next summer and with my Cruiser not my DD, I doubt those tires will even see 10K before I swap them out.

In hindsight, I probably should have just put some used tires on but WalMart gave me a helluva online deal for the set of 5 at $539 (with mounting and balancing AND lifetime warranty on each tire...and yes, I got it in writing that they understand when one tire is replaced, ALL have to be replaced under warranty).
 
I'm happy when I get 11, thrilled when I touch 12. But 10.5 is my average. Not much I can do other than offload all the things I've added over the years.
 
I keep all my lubricants and parts up to date so the truck is healthy and reliable, but in theory, that’s also how I’ll get my best mileage, next to driving habits. Personally, it is what it is and I’m not interested in spending extra $$ in hopes of squeezing out a few more miles per tank. I can easily save more money per month just by skipping a few beers.

The friend I bought it from let me take it on an extended test cruise, as I wanted to get an idea of the mileage I could get on a trip. Came back with 15.5 cruising at 60, which is fine by me, considering it’s a lifted 80. Otherwise, I average about 13 in general. More like 12.5 in summer when I’m driving shorter distances, and 13.5 in winter when I drive longer most days. That’s gentle driving, with a J lift and 315 ATs.
 
I keep all my lubricants and parts up to date so the truck is healthy and reliable, but in theory, that’s also how I’ll get my best mileage, next to driving habits. Personally, it is what it is and I’m not interested in spending extra $$ in hopes of squeezing out a few more miles per tank. I can easily save more money per month just by skipping a few beers.

The friend I bought it from let me take it on an extended test cruise, as I wanted to get an idea of the mileage I could get on a trip. Came back with 15.5 cruising at 60, which is fine by me, considering it’s a lifted 80. Otherwise, I average about 13 in general. More like 12.5 in summer when I’m driving shorter distances, and 13.5 in winter when I drive longer most days. That’s gentle driving, with a J lift and 315 ATs.

Yeah, we didn't buy them for the fuel economy ;)
But I applaud anyone who tries to squeeze blood (or fuel, in this case) from a stone.

I also really like reading what other people do to their rigs with issues like this.
 
Here's my daily-driver 1997 80-series for comparison.

Current setup averaging 230+ miles in-town, 260+/- in-town/highway:
  • 2.5" OME lift
  • 4.88 Yukon gearing in diffs (don't ever buy Yukon gears :banghead:)
  • Goodyear Wrangler Duratracs in 315 flavor (35's) on stock wheels
  • ARB front bumper (no winch)

Prior setup averaging 240+ miles in-town, 280+ in-town/highway:
  • 2.5" OME lift
  • 4.11 stock gearing in diffs
  • Goodyear Wrangler Duratracs in 285 flavor (33's) on stock wheels
  • ARB front bumper (no winch)

Truck is not regularly loaded up as I try not to carry too much unnecessary stuff for in-town. I do have a plywood sheet cut to size as a mounting base in the boot with Engel-35 plus rubbermaid of roadside emergency, construction site gear and other odds'n'ends. These things have lived inside the 80 since almost the beginning of ownership in 12/2013.

I keep the 315 tires inflated for street-use (40psi) and maintenance up-to-date with exception of an O2 sensor needing replacing which probably isn't helping mileage.

Also tend not to fill the OEM auxiliary fuel tank unless I'm hitting the highway for a roadtrip (if you haven't experienced it, watching your main tank fill-up with gas while rolling down the highway is the s***).

Increasing tire size was the real mileage killer going from 285 to 315 but likely would've been worse if I hadn't re-geared (did I mention not to buy Yukon gears? :banghead:). I do recall being amazed at the highway mileage I got on 285 and stock gears but, y'know, 315 just looks so choice so now I pay for it 💸💸💸.

If anyone's interested follow this LINK to gearing calculations between stock 4.11, 4.56 and 4.88 or check out the pic below.

80 gearing.JPG
 
Here's my daily-driver 1997 80-series for comparison.

Current setup averaging 230+ miles in-town, 260+/- in-town/highway:
  • 2.5" OME lift
  • 4.88 Yukon gearing in diffs (don't ever buy Yukon gears :banghead:)
  • Goodyear Wrangler Duratracs in 315 flavor (35's) on stock wheels
  • ARB front bumper (no winch)

Prior setup averaging 240+ miles in-town, 280+ in-town/highway:
  • 2.5" OME lift
  • 4.11 stock gearing in diffs
  • Goodyear Wrangler Duratracs in 285 flavor (33's) on stock wheels
  • ARB front bumper (no winch)

Truck is not regularly loaded up as I try not to carry too much unnecessary stuff for in-town. I do have a plywood sheet cut to size as a mounting base in the boot with Engel-35 plus rubbermaid of roadside emergency, construction site gear and other odds'n'ends. These things have lived inside the 80 since almost the beginning of ownership in 12/2013.

I keep the 315 tires inflated for street-use (40psi) and maintenance up-to-date with exception of an O2 sensor needing replacing which probably isn't helping mileage.

Also tend not to fill the OEM auxiliary fuel tank unless I'm hitting the highway for a roadtrip (if you haven't experienced it, watching your main tank fill-up with gas while rolling down the highway is the s***).

Increasing tire size was the real mileage killer going from 285 to 315 but likely would've been worse if I hadn't re-geared (did I mention not to buy Yukon gears? :banghead:). I do recall being amazed at the highway mileage I got on 285 and stock gears but, y'know, 315 just looks so choice so now I pay for it 💸💸💸.

If anyone's interested follow this LINK to gearing calculations between stock 4.11, 4.56 and 4.88 or check out the pic below.

View attachment 3063370

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.
 

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