Gas milage and speed...

[Esther]

Hey All,
I keep reading a lot of you talking about getting 10 mpg with your 60. For a while now I have been monitoring my milage pretty close and am getting about 13.6mpg. Now my truck is totally stock, no big wheels, no headers or any engine mods, I even have all the emissions stuff still on. Maybe an 86 fj60 is supposed to get 13-14 mpg from the factory, I don't know. What I do know is that I keep my foot out of the pedal, I drive slow, never above 62-64, I even give 55 a try now and then. No fast starts etc. And I keep everything tuned all the time; I change my oil every 2000 miles. The carb has never been rebuilt and that little cap on the back that keeps you from messing with the mix they install at the factory is still in place. Am I lucky with 13.6mpg? I recall reading someone here saying that he likes his 60 because it forces him to drive slow and relax. I have to agree.
In the big scheme of things, 13.6 mpg really is not good, but for the 60 and me, it is great.
Is there anyone else out there with a stock 60 like mine? Even the folks who swap things out, what do you think you best gas improving mod is? I am of the mindset that the engineers in Japan may have designed this motor to perfection when it comes to MPG. Thoughts?
John

 

[Front Range 4x4]

I get an average of 13.8 mpg on my 62 during normal driving which I think is pretty damned good. The way you drive has a huge impact as you show from your experience. As a test this summer I decided to go heavy on the throttle driving across Colorado and Utah at 80-90 mph - the fuel consumption was outrageous, I could almost watch the gas gauge drop. It appears that the 62 is most efficient at 2500 rpms which is where i try to keep it on the highway and suspect the 60 is much the same.

 

[silicon_toad2000]

the engine in these beastys is not very efficient in terms of fuel usage. There are plenty of guys here who have dumped in a SBC and seen an increase in mileage.
My understanding is that the engine is based on a design of a GM 6 deisgned in the 30's. Japan bought the design and the moulds when GM finished with them. I could be mistaken though.
Without cracking open the engine, just keep her tuned, correct tyre pressures and not carrying any more weight than you need is about all you can do.
I put an electric fan on mine but the mpg reults have been negligible.
With these I think the MPG is driven very much by the inefficiencies of the engine and the lack of aerodynamics.

 

[RayN]

I consistently get 15mpg out of my '82 around town. I have slightly larger tires than stock but other than that mine is completely stock with all the emissions equipment. I consciously try to keep the rpms low when I drive. When I'm on the freeway my mpg will actually drop to 13-14 (3000rpms).

 

[smkymntn]

I am getting around 15-16 with a very light pedal- I shift at 2k or under and take advantage of the downhills, mostly using the engine for braking. I am full desmog, rebuilt carb, and perfectly tuned. I love driving my 60- it is the most relaxing car to drive. I have 32" tires.

 

[fliphkd778]

I agree, I was running stock with 32x12.5" tires and was getting 13-14 in city traffic. My compression was only at around 130psi with 16" of mercury with bad valve flutter. I typically shifted at around 2200 to 2400 around town, which is very flat and has no hills. Since then, I've rebuilt my head and now have 160psi and 20" of mercury, no smog and headers. That setup is getting me around 6mpg. So I've got some things to sort out.

 

[AustinMiniMan]

My '84 60 with 155K gets 14.9-15.2MPG on every tank. Most of my driving is highway at about 65MPH. She's completely stock except being de-smogged. I never thought it was great, but now I guess I shouldn't complain.

And to be honest, I drive her pretty hard... I normally shift at 2,000; but I have to do a lot of passing(2 lane country roads), so she sees 75-80MPH pretty regularly, which of course is foot to the floor.

 

[cruiserunc]

Fuel Mileage

I have an 86 FJ 60 with a 13B-T harvested from a BJ74 with a 5 speed. I just filled up this afternoon and the mileage was 23.66 mpg. That involves driving mostly on a two lane US 15-501 and four lane US 1. Nothing with high speeds and some around town stuff but probably the two things that limit some of my mpg is the tires and steel (heavy tires/305/75/16 Goodyears, an ARB front bumper and Westin Sliders).

I think the actual numbers were in the area 479 miles driven and 20.7 gallons to fill the tank until it was packed full.

If I push it I can get 525 miles before I am cutting it too close and if I am easy on it with the smaller tires (275/70/16 michelins) I have driven more than 600 miles on a tank and have measured 26.1 mpg. Stickboy who built this rig reported being able to get 28 driving it easy from Moscow ID to Spokane WA on 15's but I have not been able to replicate that level of MPG.

Now, diesel costs more but I more than make up for it with the MPG.

 

[UglyFJ60]

when I factor in my odometer being about 10% off (registers 10% less than actually driven) with the 33's, no choke, and POS weber carb I am gettinn 11.5. before the new clutch I got anywhere from 6 to 8. Figure I was losing 1000 RPMs to slippage.

 

[forestdan7]

With the stock tire size being 28", you're probably closer to 17% off on your speed and mileage with 33s, assuming you have stock rear end gears. I use 10% for the difference between my 31s and the stock 28s.

Making this correction, I normallly average about 16.5 mpg, with mostly highway miles. I drive slow, and never make it to 70 mph true speed. Driving around town a few weeks back, it got as bad as 12 mpg on half a tank.

But, and this happened twice on the same trip so I figured it was real, I got 19.8 mpg driving from eastern Kentucky to Athens, Georgia, and back, over the Blue Ridge. 19.8, then 16, then 19.8 again. I usually fill up at about 1/2 tank, and I calculate it every time.

Stock 2f, stock smog equipment, K&N air filter, tuned up, with 31s, and H55F. I'd say 5th gear helps a good bit. I cruise on the highway around 2000 rpm.

 

[brian]

about 12mpg. mostly city.
33"s 3:70's full desmog, weber 38(w/oem paper filter), headers.
i drive her pretty good, cause she goes.
normally shift around 2500, rarely cruise above 2600.
lots of red lights. try as i might i can't ease away from them it's not foot to the floor, but harder then i could be.

 

[landcruiserjunky]

I probably average 13 around town. I consider that really good considering how much crap I have on my landcruiser.

 

[tigerfan2468]

I have an 84 FJ60 with 31s on the rims and always get 14 mpg regardless of highway or city. I take her up to 75-80 mph no problem.