I’m getting 12 mpg on a good day. How can this be improved

 

On a Toyota Prius, that's horrible. On a road grader, that's great.

 

If you’re talking about the 460 gasser. Anything over 10mpg is wonderful. You can’t really improve much over your current mpg

 

Inspect and fix anything that is not working properly. Brakes, vacuum lines, etc. Thorough tune up. Make sure the computer is happy. If the fluid service history is unknown change the functional fluids.

After all that the most effective way to get better fuel economy is smaller tires or deeper gears.

If the truck is in decent shape as is and you don't want to sink a bunch of time and money in it then drive something else when you don't need a truck.

 

is that how much you get?

 

when I had my 79 f150, I got between 7-11 mpg most of the time. Some tanks were closer to 5-6 mpg. They just love gas stations

 

I drove my '92 F250 from Portland, OR. to "Minne-a-no-place" not too long ago, and the best I got with it on the freeway/interstate was just a hair over 12.5. And I was being careful....

I have the original window sticker for my truck at home, and at the bottom where they normally put the MPG number, it says "Not Applicable", or something like that. (Wish I had a photo of that right now...)

 

Yes. F-250 and heavier did not have to meet fuel mileage requirements so the city/highway numbers were not included on the window sticker.

 

I wasn't aware of that, thanks!

Makes me chuckle a little as sometimes I, like the OP, start thinking about how to improve the MPG of that truck.

But then I remember that little disclaimer on the window sticker, and consider what I intended on using it for when I bought it!

 

Many years ago, a major truck magazine did a report on the F350 460 EFI to test MPG claims.

The things that really made a difference were the Gear Vendors over/under drive. Past that, cold air to the engine and some additives to keep the engine cooler. One I think was Water Wetter and then BeCool for the oil. I think the same thing can be had with a large cooling system for both oil and water.

IDR if they dropped the TStat temp or messed with anything else.

One thing that I don't remember is if they did headers and/or cat delete and/or cat back systems.

I hear that things like straight up timing, cooling and exhaust can add up.

The gains from the GV over/under was something like 11%, so maybe 2 MPG? I'm pretty sure it was the C6, so if you already have OD, then maybe a gear change and double OD might see a gain, but that's really pretty expensive.

 

What year 460/7.5L truck?

With a EFI 7.5L/E4OD trans I get 11.5mpg pretty consistently, and that's with 4.10 rear gears, too!

These things are aerodynamic BRICKS, so speed will be a HUGE factor in MPG. Keep it under 60, and gas mileage improves a bunch. Over 70, and you wan watch the needle drop.

Likewise, anything you can do to improve aerodynamics will help. a bed cover/tonneau cover is good for almost 1mpg at highway speeds because it will cut down on the turbulent airflow behind the cab..

My trucks both have/had 235/85-16 10-ply highway-tread tires. 'Mudder' deep tread off-road tires will cost you 1mpg or more.

 

My 302 gets around 8-10 only driving around town, recently I took a just a couple longer trips and calculated about 13.8.

Id love to see what I can get on full highway miles.

 

Another way of thinking about it is this....

You drive a giant brick, disguised as a truck.

GPM is the thing you could be looking at.

 

If not towing max weight, go with D code tires. Less rotational mass. Steel rims? Go to aluminum, OE Alcoas all over for SRW. Basic physics.

60-65mph about it for econ. Try a vacuum gauge, find sweet spot for highest point of vac and there ta go.

Stock BBF exhaust decent, cat is huge and probably flows poor. Rear muffler? No idea. Modern three way cat and muff may help, but doubt you will see 1mpg gain.

Could be worse...could own and drive a 7.3DI. Four gallons of oil. $2000 injectors. Etc.

Best advice posted? Buy a beater car if truck not needed.

 

Yeah, I have civic that i daily but was just looking for tips. where can I get a vacuum gauge