New Here and have a few ??? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Frugal1 · 06-30-2004, 04:38 PM

I just bought a 70 GMC pick up and wanted to know a couple of things.

#1. What kind of gas mileage can I anticipate?
#2 What can I do to improove it ?
#3 How much does it weigh ? 8' box, 350, Automatic.

Thanks in advance and I will post pictures soon.

Kevin

LUV2XCLR8 · 06-30-2004, 05:02 PM

WELCOME 2 THE BOARD FROM W. TN.

1.) GAS MILEAGE DEPENDS ON ENGINE, I GOT 8 MPG IN MY 67 W/ A 400
SB AND I GET ABOUT 20 IN MY 70 W/ 250 INLINE 6 AND 4:10 GEARS.

2.) IMPROVEMENTS UNLIMITED TO THE POCKET BOOK & IMMAGINATION
CHECK THE PICTURES BOARD AND THE PARTS BOARD FOR IDEAS :p

3.) MY 67 SWB FLEET WEIGHED 3400, MY 70 SWB STEP WEIGHED 3500

HOPE THIS HELPS YOU TO SOME DEGREE

LONGHAIR · 06-30-2004, 05:06 PM

There are way to many variables to even guess.
Rear gear ratio will determine a lot as will:
State of tune
Driving Style and intended use
Carburetor
Engine modifications?

Other than a good tune-up the best improvement in fuel mileage will come from a gear change or an overdrive transmission like a 700r4.
Depending on what rearend you have (1/2 or 3/4 ton?) you can probably get the gears for around $150-$200 and have them installed for around $200 plus gasket/lube and any bearings you might need. Or you might find an entire housing with the right ratio already inside and swap them.
The transmission will cost more initially but in my opinion give you better overall performance. It has a lower 1st gear for better pulling/hauling and overdrive for highway crusing. You will also have a TH350 to sell and recoup some of your investment.

krue · 06-30-2004, 09:12 PM

Welcome to the board from South Mississippi! If you go the od tranny route, consider the 200-4r, it's easier to install in place of the 700r4

**Palf70Step** · 06-30-2004, 09:42 PM

Welcome from south Mississippi. Ditto on what the others said. Biggest thing in gas mileage is probably your driving style, engine condition, then rear gears. Probably on the average truck, I'd say in the range of 12-13mpg around town.

*dtlilly* · 06-30-2004, 10:34 PM

Welcome to the board from a transplanted Memphian. Gas milage is just a bit under any new truck off the lot, but your driving something way cooler!

**Stocker** · 06-30-2004, 11:34 PM

Welcome from NorCal! Ditto what others said - and if your 350 has a 4-barrel carb, don't expect great fuel mileage! Is yours a 2WD? That'll help some too - my 72 4WD weighed in at 5300#....

Blue Beard · 07-01-2004, 07:08 AM

Welcome from SW Washington State...

Bowtie67 · 07-01-2004, 08:38 AM

Quote:

Originally Posted by LUV2XCLR8

3.) MY 67 SWB FLEET WEIGHED 3400, MY 70 SWB STEP WEIGHED 3500

Not to steal the thread But,
How are you gettings these weights, Are you loading up the truck with helium or what? The average weight on these is around 3800 - 4000lbs

And welcome from New Hampshire

*chevytruckfan* · 07-01-2004, 08:58 AM

Welcome from Tampa FL, Where you at? We also want pics of the truck

A few 72's · 07-01-2004, 09:21 AM

Frugal1
Welcome from Alabama.

Bowtie67
I kinda figured the fleet bed was heavier, but had I seen the trucks.
70 has front and rear bumpers off and inline 6. May be the differnce?
I know his 67 was set up for drag racing and had the front inter fenders out, not sure about the bumpers or what else may have been done to reduce weight?

gr8scott51 · 07-01-2004, 09:41 AM

Howdy from normally soggy western Washington.

ACES · 07-01-2004, 11:16 AM

Quote:

Originally Posted by Bowtie67

Not to steal the thread But,
How are you gettings these weights, Are you loading up the truck with helium or what? The average weight on these is around 3800 - 4000lbs

And welcome from New Hampshire

3800 minus 600 pounds of rust = 3200

just messin around, I have no idea what mine weighs.

06-30-2004, 09:12 PM	#4
krue Designated A-hole! Join Date: Mar 2003 Location: South Mississippi Posts: 36,450	Welcome to the board from South Mississippi! If you go the od tranny route, consider the 200-4r, it's easier to install in place of the 700r4 __________________ "If it ain't broke, fix it 'til it is!" Being stupid ain't illegal. We're Still Debt Free Except for the House!!! www.daveramsey.com 70 GMC SWB Stepside project "Green Booger" soon to be 6.0l/4l80e 93 S-10 "Poppaw's Truck"

06-30-2004, 09:42 PM	#5
Palf70Step State of Confusion! Join Date: Jul 2002 Location: Gulfport, MS USA Posts: 46,762	Welcome from south Mississippi. Ditto on what the others said. Biggest thing in gas mileage is probably your driving style, engine condition, then rear gears. Probably on the average truck, I'd say in the range of 12-13mpg around town. __________________ Bill 1970 Chevy Custom/10 LWB Fleetside 2010 Toyota Tacoma PreRunner SR5 Double Cab - DD Member of Louisiana Classic Truck Club (LCTC) Bill's Gallery Life isn't tied with a bow, but it's still a gift. Live simply. Love generously. Care deeply. Speak kindly. Leave the rest to God!

06-30-2004, 11:34 PM	#7
Stocker 20' Daredevil (Ret) Join Date: May 2003 Location: Jefferson State Posts: 13,580	Welcome from NorCal! Ditto what others said - and if your 350 has a 4-barrel carb, don't expect great fuel mileage! Is yours a 2WD? That'll help some too - my 72 4WD weighed in at 5300#.... __________________ - Mike - 1972 K20 LWB 350/350/205 RIP El Jay

07-01-2004, 07:08 AM	#8
Blue Beard Registered User Join Date: Jan 2003 Location: Washington State Posts: 8,834	Welcome from SW Washington State... __________________ 1970 Chev CST 2003 Harley Fatboy 1975 Chevrolet Step Van 1956 Chev Bel Air 1977 Blazer 2WD For Sale $3000.00 1978 Blazer 2WD For Sale $7000.00 1978 Silverado 2005 Monte Carlo

07-01-2004, 09:21 AM	#11
A few 72's Registered User Join Date: Mar 2004 Location: Alabama Posts: 705	Frugal1 Welcome from Alabama. Bowtie67 I kinda figured the fleet bed was heavier, but had I seen the trucks. 70 has front and rear bumpers off and inline 6. May be the differnce? I know his 67 was set up for drag racing and had the front inter fenders out, not sure about the bumpers or what else may have been done to reduce weight? __________________ 1972 C10 SWB 350 / T400 1972 SWB GMC 350/T350 1972 Cheyenne 20 super "long horn". 402BB / T400 1972 Suburban C10 Deluxe 350 / T350 and a few more.. http://www.myspace.com/afew72s

06-30-2004, 04:38 PM	#1
Frugal1 Registered User Join Date: Jun 2004 Location: Edmonton , Alberta , Canada Posts: 2	New Here and have a few ??? I just bought a 70 GMC pick up and wanted to know a couple of things. #1. What kind of gas mileage can I anticipate? #2 What can I do to improove it ? #3 How much does it weigh ? 8' box, 350, Automatic. Thanks in advance and I will post pictures soon. Kevin

06-30-2004, 05:02 PM	#2
LUV2XCLR8 The LuvShack Garage Join Date: Jan 2004 Location: Maple Grove, TN (West Side) Posts: 30,475	WELCOME 2 THE BOARD FROM W. TN. 1.) GAS MILEAGE DEPENDS ON ENGINE, I GOT 8 MPG IN MY 67 W/ A 400 SB AND I GET ABOUT 20 IN MY 70 W/ 250 INLINE 6 AND 4:10 GEARS. 2.) IMPROVEMENTS UNLIMITED TO THE POCKET BOOK & IMMAGINATION CHECK THE PICTURES BOARD AND THE PARTS BOARD FOR IDEAS :p 3.) MY 67 SWB FLEET WEIGHED 3400, MY 70 SWB STEP WEIGHED 3500 HOPE THIS HELPS YOU TO SOME DEGREE __________________ Owner/Op: "TN Classic Transport Carriers" The Toy: "Square Vette" 72 Hybrid Blazer Toy Barn: "LuvShack" 40 x 60 x 20 Shop Big Piggy: "Goliath" 07 Kodiak C4500 Lil Piggy:"Maddy" 88 Silverado 3500 Hauler: "Feathers" 14 Aluma 8218T

06-30-2004, 05:06 PM	#3
LONGHAIR just can't cover up my redneck Join Date: May 2004 Location: Columbus OH Posts: 11,414	There are way to many variables to even guess. Rear gear ratio will determine a lot as will: State of tune Driving Style and intended use Carburetor Engine modifications? Other than a good tune-up the best improvement in fuel mileage will come from a gear change or an overdrive transmission like a 700r4. Depending on what rearend you have (1/2 or 3/4 ton?) you can probably get the gears for around $150-$200 and have them installed for around $200 plus gasket/lube and any bearings you might need. Or you might find an entire housing with the right ratio already inside and swap them. The transmission will cost more initially but in my opinion give you better overall performance. It has a lower 1st gear for better pulling/hauling and overdrive for highway crusing. You will also have a TH350 to sell and recoup some of your investment.

06-30-2004, 10:34 PM	#6
dtlilly Account Suspended Join Date: Jan 2003 Location: Shadow of Lambeau Field Posts: 5,597	Welcome to the board from a transplanted Memphian. Gas milage is just a bit under any new truck off the lot, but your driving something way cooler!

07-01-2004, 08:58 AM	#10
chevytruckfan Account Suspended Join Date: May 2004 Location: Lake Placid, Florida Posts: 930	Welcome from Tampa FL, Where you at? We also want pics of the truck

07-01-2004, 09:41 AM	#12
gr8scott51 Registered User Join Date: Mar 2003 Location: Bremerton, WA Posts: 1,839	Howdy from normally soggy western Washington. __________________ Silence is golden, duct tape is silver. - Scott



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