is this right? fuel mileage in my truck sucks

[67cst]

hey guys, i put 70 bucks of propane in the truck exactly 1 week ago. i drove 280 miles or 450 km in the last 7 days. propane is 56 cents a litre or 2.11 a gallon. so i figure i go 280 miles divide by 33 (galons burnt) and i come up with just over 8 miles to the gallon..is this right? that is pretty poor mileage for a 350 on propane isnt it? maybe im an idiot and i did this all wrong, i sure hope so...if im right what kinda things can i do to improve mileage, btw i drive the truck like an old man, im not pinning it every chance i get

thanks Derek

[Longhorn Man]

Ouch...2.11 a gallon..what does gas cost?

[Longhorn Man]

Wait...i just realized that 2.11 there isn't all that bad on our dollar...I forgot the 5 to 1 exchainge rate. Just messin.
But seriously..what is a gallon of gasoline cost?

[500HP/SB]

haha i'm here in so cal (with gray dorkus) and i get about 7mpg (i run dual quads ) gas is $2.09 a gal for regular

[lukecp]

You did the math right...8.52 mpg.

That is really poor mileage...my built 350 gets about 11-13 running premium gas. Still expensive to drive though...

How long has it been since the truck has had a tuneup? I'm not familliar with propane vehicles, but if you have old crappy igniton componets, it will hurt your gas mileage and power. Also check the igniton timing, and make sure your air filter is clean.

[67cst]

what kinda things should i do that could help the mileage, im on a budget but im open to any ideas, besides air filter do you think plugs and wires would help? or cap and rotor? i dont know anything about propane so im lost there, is there any kind of filters or things with propane systems that should be maintained, help me out here guys!

[68 Suburban]

You will get 10-20 percent worse fuel mileage with propane than you will with gasoline. The advantages is, that it is cheaper and cleaner. By the way, I passed a station on the Arizona-New Mexico boarder that propane was 89 cents a gallon!!

[tom hand]

Apples and oranges...Gas has 144,264 BTU's per gallon, propane has 84,000 BTU's per gallon, or about 74%. So you are looking at 26% worse milage to get the same power. Change your math and figure how many cents it takes to go per mile, and compare it to gas, then you will be happy. Going by this you would be getting about 11 mpg on gas which is about right.

[FRENCHBLUE72]

Are you sure the speedo is right? I thought I was getting 7 in my blazer but came to the conclusion that my speedo was not accurate after driving by one of those radar trap's..

[67cst]

no the speedo is bang on..thanks for the info guys

[swb70]

Het 67cst and anyone else using propane. I started using the stuff in 1966 when it was 10 cents a gallon. Ran it on
6's and 8's with the same results. about 10MPG. Here in Texas
you have to pay the taxes upfront every year. In my case
that was about $184 for a tax sticker.It was required by law
or the dealer would not sell you any gas. Dont understand why the Gov. did that, when they holler about smog. Propane is cleaner and will keep your engine cleaner also.

[Chevyguy111786]

my speedo is wrong...when it says i'm doing 30 i'm really doin 35. How would that affect my gas mileage, better or worse. Right now when i figure it up it come to 7 mpg. I have a 350/350 and a vintage air ac unit. i should be gettin better i think

[lukecp]

With the corrected speedometer, you should be getting about 8.2 mpg Chevyguy.