10mpg

[sonofmayhem]

1985 4x4 EFI SR5 Pickup, is getting 10mpg I have replaced the clutch and radiator in the last 3500miles, and in the last 400miles i have replaced or gotten done:

fuel filter
spark plugs, wires
oxy sensor
brake system
front axle seals, and bearings
trany flush
4x4 tune up
oil change
Air filter
distributor cap and button

i have a 3in lift, and 30in tires. my dad ran 33s and gotten 75miles every quarter on average.. is there anything i can get done, or replace to get my MPG back to normal?
THere is no check engine light.

Thank You


Thank You

[humanoid]

Maybe need to re-gear or get your speedo recalibrated. Did you change your fuel filter as well?

[sonofmayhem]

yes i replaced the fuel filter last thursday, i dunno what the gearing is, but the speedo is dead on. i was thinking it was my gas gauge, because it fluxuates alot, but when i was parked on a hill and tried to start it, i had to give it some gas. I will ask my dad what gearing he put in it.

THanks

[smasheromalley]

Just curious but how are you calculating your mpg? Like what method are you using?

[smasheromalley]

I ask cause my 87 4spd dually just got 24mpg and 100 of those miles were towing a 2 place quad trailer. 10 mpg just doesnt sound possible unless theres gas dripping from underneath the truck

[supraman215]

Originally Posted by smasheromalley

Just curious but how are you calculating your mpg? Like what method are you using?

This is a good question. Fill it up to the top (till the automatic filler stops) and go 50 miles, then fill it up again to the top, mark down the gallons used to fill it up. Do that 2 or 3 times in a row and you should be able to get a good average. Gas gauge on the dash will be extremely inaccurate nearly all the time for determining MPG.

[sonofmayhem]

i would fill it up and reset the tripometer and i have a 17gallon tank, so when i got down to 1/4 of a tank left i would divide the miles, by the gallons used, 12.75gallons, so is this method wrong? i thought it would work. Is it normal for the gas gauge to fluctuate in between two marks?Ex: full - - 3/4

[sonofmayhem]

UPDATE

There is no leaking under the truck. But could the gas evaporate before it hit the ground? because of the engine heat?

[texas12]

It is inaccurate to say that first 3/4 of a tank is 12.75 gallons. Do what SUPRAMAN suggested. If you run it to 1/4 tank, refill it until it auto-stops and divide the actual mileage by the actual gallons pumped.

[4x4Runner]

If you lift your truck and have 33in tires your gonna have bad gas mileage.

[4x4Runner]

In 85 the pick up didn't have fuel injection. That could be one of the reasons you get bad gas mileage. Its time to buy a new truck. Your trucks 20 years old now.

[smasheromalley]

Originally Posted by texas12

It is inaccurate to say that first 3/4 of a tank is 12.75 gallons. Do what SUPRAMAN suggested. If you run it to 1/4 tank, refill it until it auto-stops and divide the actual mileage by the actual gallons pumped.

Thats pretty much what I do. I usually run it close to E then fill it and top it off to the nearest $.25, then divide miles by gallons pumped. It gives a pretty good running total.

I didnt take into account the fact your truck is carbed, 4x4 and lifted... but still... 10 mpg is pretty bad...

[sonofmayhem]

I beg to differ the 85 was the first year for EFi, and the last year for the SFA. I appreciate your help. I am getting a new truck in Nov. so im tryin to get by with this thing.

Thanx

[4x4Runner]

Originally Posted by sonofmayhem

I beg to differ the 85 was the first year for EFi, and the last year for the SFA. I appreciate your help. I am getting a new truck in Nov. so im tryin to get by with this thing.

Thanx

What kind of truck are you considering?

[sonofmayhem]

However, earlier this year it was doing fine w/ 23+mpg. Never any serious rock crawling, type offroading, or pulling anything, or any engine overheating. What could i do to find leaks, other than the obvious, look, is there a chemical like for a/c or do i have to look with my EYES?

TY