The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 08-10-2009, 10:35 AM   #51
C-10 simplex
Account Suspended
 
Join Date: Dec 2008
Location: indisclosed
Posts: 1,515
Re: What's your fuel Mileage?

About 16ish mostly highway driving.


But for anyone serious about mpg, please read my very drawn out, thourough, anal, and scientific research thread on mpg:

http://forum.73-87chevytrucks.com/sm...p?topic=8474.0


P.S., i feel that tires could make all the difference in the world; i would be looking at michelin X.
C-10 simplex is offline   Reply With Quote
Old 08-10-2009, 04:24 PM   #52
Robert1970C20rstbukt
Registered User
 
Robert1970C20rstbukt's Avatar
 
Join Date: Jun 2004
Location: Beeville, Texas
Posts: 1,943
Re: What's your fuel Mileage?

1984 Chevy regular cab flatbed dually, 454 with 2 1/2" dual exhaust and 12" chamber glasspacks(nice and LOUD ), stock air breather and Qjet, SM465, 4.10 gears, 235/85/16 rubber at 60psi. Right now I get about 6-7 in town and highway is close to 14, that's doin' around 50-55. Any higher and the gas gauge moves to the left real quick.
__________________
RJD

1984 Chevrolet C30 welding truck 454/SM465
1977 GMC C15 pickup 350/TH350
1970 Chevrolet C20 pickup 350/TH400
1970 Chevrolet K20 Suburban 454/TH350
1969 GMC 8500 478M V6/5 spd winch truck
Robert1970C20rstbukt is offline   Reply With Quote
Old 08-10-2009, 10:13 PM   #53
thirdstreettito
Resident of Here
 
thirdstreettito's Avatar
 
Join Date: May 2008
Location: Wesley Chapel, FL, USA
Posts: 7,716
Re: What's your fuel Mileage?

My diesel gets 22hwy, but I was doing 75-90, if I did 60-70 I'd probably get 25 easy.
__________________
~Bradley~
2004 Black GTO LS2/T56 too much to list

Miss having a truck
thirdstreettito is offline   Reply With Quote
Old 08-10-2009, 10:27 PM   #54
Bow Tie Scottie
Registered User
 
Bow Tie Scottie's Avatar
 
Join Date: Nov 2008
Location: Duluth, GA
Posts: 80
Re: What's your fuel Mileage?

Why would you ask? O.K., my 86 gets about an average of 8 to 10. BTW, I hope the feds aren't looking.
Bow Tie Scottie is offline   Reply With Quote
Old 08-10-2009, 11:34 PM   #55
Eyegore
What Hump?
 
Eyegore's Avatar
 
Join Date: Apr 2003
Location: New River AZ
Posts: 2,009
Re: What's your fuel Mileage?

Quote:
Originally Posted by 78 Big10 454 View Post
Stock 454 with a TH400:

10 mpg on a good day.
10 mpg on a bad day
10 mpg highway.
10 mpg city.
10 mpg empty.
10 mpg loaded.

Did I miss anything?
Yes :
10 mpg uphill
10 mpg downhill
__________________
Lil red 86 c-10
99 Sub
78 Camper Special w/ 454
Eyegore is offline   Reply With Quote
Old 08-14-2009, 11:59 AM   #56
Adams74Chevy
Registered User
 
Adams74Chevy's Avatar
 
Join Date: Mar 2009
Location: MD
Posts: 417
Re: What's your fuel Mileage?

Quote:
Originally Posted by 78 Big10 454 View Post
Stock 454 with a TH400:

10 mpg on a good day.
10 mpg on a bad day
10 mpg highway.
10 mpg city.
10 mpg empty.
10 mpg loaded.

Did I miss anything?
Sounds like my father talking about my '74 K20 when people asked him what he got with it... after they'd have their OMG moment he'd calmly say well I bought it to haul not to drive to all over the countryside and it hauls as good as or better than these guys with their new trucks their still making payments on.
__________________
2006 Silverado Crew Cab 1500 4x4 5.3L automatic
1986 M1008 CUCV 6.2L Detroit Diesel TH400 4.56 Detroit Locker rear NP208
1973 K20 "Silverado" 350ci, HEI, TH350, NP203 with 2wd conversion, A/C, power windows,tilt wheel, dual tanks. My '73ish K20 thread My 5yo son claims it as his.
1987 V20 Custom Deluxe 350 TH400 NP208 "farm truck" getting parted out.
2016 Nissan Altima grocery getter/commuter
Adams74Chevy is offline   Reply With Quote
Old 08-14-2009, 12:34 PM   #57
Scootin 81 C20
3/4 Ton Rodder
 
Scootin 81 C20's Avatar
 
Join Date: Jan 2009
Location: Manlius, IL
Posts: 1,146
Re: What's your fuel Mileage?

Quote:
Originally Posted by 78 Big10 454 View Post
Stock 454 with a TH400:

10 mpg on a good day.
10 mpg on a bad day
10 mpg highway.
10 mpg city.
10 mpg empty.
10 mpg loaded.

Did I miss anything?
10 mpg during the day.
10 mpg at night.

Mine, if I did the math right, I get about 12 mpg with my 350 Quadrajet TH400. That is, if I can keep my foot out of it.
__________________
1981 Chevy Scottsdale C20 "Orange Crush": SOLD

1989 Chevy Silverado K2500: All Stock (For Now), 350 TBI/700R4. DD/Light Duty Toy.
Scootin 81 C20 is offline   Reply With Quote
Old 08-14-2009, 02:08 PM   #58
nlped
Senior Member
 
nlped's Avatar
 
Join Date: Jul 2009
Location: Hayden, Al.
Posts: 4,148
Re: What's your fuel Mileage?

I average 14-16 mpg with mixed driving. I have gotten 18 mpg once on a road trip running 72 in the fall w/ no air running. '87 GMC 2wd w/ 350 TBI, 700r4, & 3.42 rear. But I had the stock 2.73 rearend when I got the 18 mpg.

Cheers,

Ed
__________________
Carter

1968 Chevy SWB Fleet... Walt


1963-1/2 Ford Falcon Futura...Martha
nlped is offline   Reply With Quote
Old 08-14-2009, 09:36 PM   #59
Stitch
Account Suspended
 
Join Date: Jul 2008
Location: Where I come from, it's cornbread and chicken...
Posts: 3,122
Re: What's your fuel Mileage?

I get 26 city/22 highway

1/2ton swb 2wd, 6.2 diesel, 700r4, 3.42 gear...

and the injection pump is turned up some...go figure
Stitch is offline   Reply With Quote
Old 08-15-2009, 04:42 PM   #60
KQQL IT
At the body shop.
 
KQQL IT's Avatar
 
Join Date: Aug 2009
Location: Land of fruits and nuts.
Posts: 5,257
Re: What's your fuel Mileage?

Hmmm when the gauge says 1/8th its time for more gas... I thought it was more about smiles per mile
__________________
" That didnt make it any newer "
" Dont antique the equipment "
KQQL IT is offline   Reply With Quote
Old 08-15-2009, 05:39 PM   #61
Dave Kay
Registered User
 
Dave Kay's Avatar
 
Join Date: Dec 2006
Location: Victorville, CA
Posts: 68
Re: What's your fuel Mileage?

Quote:
Originally Posted by flamingbig10 View Post
I had one but it was messed up by the past owner and was only getting 5 mpg on good day so got a rebuilt quadra jet and no luck couldn't get it tuned wright so I took it to a couple old school mechanics no luck it do good for a wile then next day it will bog down like crazy and spit and sputter, but I'm saving for a new carb so then I should be getting 8 or better
Hey now! Get that Q-Jet done up right at this place http://www.smicarburetor.com/

Highly reccomended, SMI's carbs will make your truck run like a top right outta' the box!

BTW: my '86 GMC C3500 gets around 11 to 14 mpg if I cruise it real nice-like... also, make sure you go over THE WHOLE fuel system before you put a new carby on anything; clean fuel is a must!
__________________
Dave Kay is offline   Reply With Quote
Old 08-15-2009, 05:45 PM   #62
Manbearpig
Registered User
 
Manbearpig's Avatar
 
Join Date: Mar 2009
Location: Midland, Tx
Posts: 418
Re: What's your fuel Mileage?

About 5MPG in the K5

14 City/17 Highway in the 04 Sierra
__________________
1972 GMC C10
Manbearpig is offline   Reply With Quote
Old 08-16-2009, 04:55 AM   #63
tecky11
Registered User
 
Join Date: Jan 2009
Location: phoenix,AZ
Posts: 451
Re: What's your fuel Mileage?

72 3/4 intl 2wd 3.73 3speed auto 9-10 if im nice 8-9 with lead foot
tecky11 is offline   Reply With Quote
Old 08-16-2009, 04:55 PM   #64
larrystone
Registered User
 
larrystone's Avatar
 
Join Date: Jan 2008
Location: White Haven PA
Posts: 59
Re: What's your fuel Mileage?

21 mpg highway

Stock 4.3 4v/th350c/2.73/26" tall tires
__________________
1992 C1500 WT LWB 4.3TBI 700r4 4.10 limited slip= Work Truck
1986 C10 Custom Deluxe LWB 4.3-4V TH350C 2.73 ac cruise tilt= Cowboy Cadillac

Last edited by larrystone; 08-16-2009 at 04:57 PM.
larrystone is offline   Reply With Quote
Old 08-16-2009, 07:12 PM   #65
RPOZ11
72 BB C30 Super LongHorn
 
RPOZ11's Avatar
 
Join Date: Nov 2002
Location: Chavez Ravine
Posts: 1,606
Re: What's your fuel Mileage?

Quote:
Originally Posted by 78 Big10 454 View Post
Stock 454 with a TH400:

10 mpg on a good day.
10 mpg on a bad day
10 mpg highway.
10 mpg city.
10 mpg empty.
10 mpg loaded.

Did I miss anything?
Same for me:

1973 Stock 454/TH400

Same results as above!!!
__________________
72 BB C/30 Longhorn Super
HO72 No-Spin, #'s matching, Tilt, Tach, AC, AM/FM


HO72 build :
http://67-72chevytrucks.com/vboard/s...d.php?t=714492

2017 SS
RPOZ11 is offline   Reply With Quote
Old 08-17-2009, 02:26 PM   #66
clinebarger
Senior Member
 
Join Date: May 2009
Location: Fort Worth, TX
Posts: 6,370
Re: What's your fuel Mileage?

My 70 gets gallons per mile my burb averages 16. the pickup 13. The biggest and heviest of my trucks my dodge dually gets the best 19-22.
clinebarger is offline   Reply With Quote
Old 08-17-2009, 02:28 PM   #67
Sniper X
Registered User
 
Join Date: Aug 2009
Location: Albuquerque New mexico
Posts: 169
Re: What's your fuel Mileage?

Quote:
Originally Posted by 78 Big10 454 View Post
Stock 454 with a TH400:

10 mpg on a good day.
10 mpg on a bad day
10 mpg highway.
10 mpg city.
10 mpg empty.
10 mpg loaded.

Did I miss anything?
Sounds like mine, 1978 454 stock but for a good air filter and it gets 10mpg no matter what the situation is!
Sniper X is offline   Reply With Quote
Old 08-17-2009, 02:47 PM   #68
rome704
Registered User
 
rome704's Avatar
 
Join Date: Feb 2009
Location: NC
Posts: 85
Re: What's your fuel Mileage?

50 feet 2 da gallon lol

more like 10 mpg
__________________
Roman "LCPL" Planter
The Few The Proud The Marines
rome704 is offline   Reply With Quote
Old 08-17-2009, 02:57 PM   #69
Sniper X
Registered User
 
Join Date: Aug 2009
Location: Albuquerque New mexico
Posts: 169
Re: What's your fuel Mileage?

When I do get the clutch in the 74, Ill bet i get about the same as the big block! The 350 never was a great gas mileage monster in a C20...even with the 4 speed.
Sniper X is offline   Reply With Quote
Old 08-18-2009, 02:04 AM   #70
texastruckjunky
Registered User
 
texastruckjunky's Avatar
 
Join Date: May 2009
Location: San Antonio,Texas
Posts: 220
Re: What's your fuel Mileage?

mine has a 454 with .505 lift cam. 1 over the RV cam. Headers 2 1/2 exhaust w/flowmasters and a factory Holly spreadbore carb. In town about 6-8 driving like grandpa. Hwy 9-11 55-60.
texastruckjunky is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 11:05 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com