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Dually Engine \  I need better mileage in my 1985 Crew cab 454

I need better mileage in my 1985 Crew cab 454

Dually Engine Dually Tech
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replies 9
following 7
565turbo avatar
565turbo   +1y
The gas price is now 10 usd pr gallon here in Denmark.

Any good sugestions
I have been thinking about these solutions. Any suggestions. What have you done. I am open for any idears
1. Newer Diesel driveline
2. Newer Gas driveline
3. Gear vendors overdrive kit
4. Newer trans with over drive

i use the truck for haulin my race car trailer a lot

I also need some accesories for the truck but it seems it is to old- Any good places to buy.
Tailgate lites
gangster cap
Hood visor. Tomount on the front on the hood
Spoiler for the cab

But the most important is mileage problem
bk2life avatar
bk2life   +1y
lol. its a crew cab big block, gas mileage are you serious? you have to pay to play.

565turbo avatar
565turbo   +1y
yes . I am seriuos.
Everything is much more expensive here. I love my car and i would like to able to drive in it also in the future.
impala_631 avatar
impala_631   +1y
Diesel swap is your best bet,,better mpgs and tons of power
big bear avatar
big bear   +1y
yea, im hugggge fan of the 454 big block. thats what i have as well, but you cannot put those words in same sentence. fuel mileage +big block = lots of gas and gpm.
565turbo avatar
565turbo   +1y
I am a fan of 454 as well , but I think in some years I am not allowed to drive this car . And I want to keep this car for many years . So I need to get something done before they make so expesive that it is not posible.

What diesel swap would be the best. Where can I get more information or is there comp
impala_631 avatar
impala_631   +1y
I would do a 12 valve Cummins swap,they get killer millage and power,plus it's one of the easier swaps, very little wiring and there are several kits to make it fit
giovanni avatar
giovanni   +1y
Buy A Vortec dually with 4l80e n that will save cash
manimal avatar
manimal   +1y
Depending on what diesel is more available in your area, that would be the FIRST choice. A gear vendor is a $3k overdrive that will not pay for itself anytime soon...if ever. A diesel powertrain will be the best. If you are not doing any HEAVY towing, then a 6.2/6.5 GM diesel will bolt into your truck without custom parts. You can keep your trans,change the converter and governor and you will be set for at least TWICE the mpg as your 454...and can run almost ANYTHING!
xltoyz avatar
xltoyz   +1y
All my time behind the wheel of my 92 gmc c3500 cc dually with the 454 and I never got better than 10mpg and that was not towing anything!

So I decided to go diesel, 1995 cummins 12v p pumped turbo diesel engine plus a nv4500 5spd transmission out of same truck.

Almost have it running and will report back on what I get for mpg but should be in the 13-16mpg towing and 18-25mpg unloaded.

I still plan to get a doug nash underdrive orverdrive box to further increase mileage including regearing truck down from 4.10 gears to 3.54 locker.

Oh did I mentioned I plan to run waste oil to burn also so basically I will run my fuel for almost free when I can get it.

Most of the info I got was from various forums like 4btswaps, cumminsforum, diesel bombers, duramax forum.

Speaking of duramax swap yeah u can do that too but its super expensive and does not make senseto make a cheap and reliable tow rig like minds, I have less than 5k into mines, down the road when things get cheaper I want to go with the new 6.7 cummins to make it nicer and quieter

Brentwood ca
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