gears and gas milage/whatcha got? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

magoo72 · 01-06-2004, 04:24 AM

what gear in the rear is the popular for gas milage ,what tranny is the favorite of my fellow truckers.
i run a 350/350turbo with 3.73 gears ,its allright for back and forth to work and local drivin and will snatch your head back into the rear window !!! but........... if i do have to get on the interstate it sounds like i am running @ Daytona. and the gas gauge falls rather quickly$$ i am building a new rear end w/3.08 gears,hoping not to sacrifice my boogidy,bogidy for better milage.
lemme know what yur running and how good is your milage/ btw i get bout 10 miles to the gal.
mr magoo

**JIMs70GMC** · 01-06-2004, 09:17 AM

4.10s, 33" tires, 8-9MPG stock 350 running a little rich.

mrein3 · 01-06-2004, 09:20 AM

3.73 gears. 350/th350. 9.5 mpg most of the time towing my boat. 13 mpg was my best ever. That was not towing and I had a good tail wind.

cdowns · 01-06-2004, 10:33 AM

4:10/200R4/275:60X15tires and i git 16.5mpg running 70-75 on the highway about 10-11 around town

lukecp · 01-06-2004, 10:41 AM

350/TH350/3.07. Usually around 12-13mpg on premium fuel...but my motor is built a little and i have a lead foot.

JimKshortstep4x4 · 01-06-2004, 11:06 AM

My son's truck is the one we use mostly and it has a 307/TH 350
with 3:07 gears. Gets 16 mpg.

Jim

zigzag · 01-06-2004, 11:27 AM

327/3spd manul/4.56 gears on a 3/4 ton truck with some 8 ply mud grips.....maybe 8 MPG

Paul72 · 01-06-2004, 11:50 AM

K/20 - 350 w/ quadrapuke, 4sp, 3.73 open, 31" tires gets 10 mpg full, empty, warm, cold, north or south.

K/5 - 350 w/ 750 Holley, TH350, 3.08 open, 31" tires gets between 9-10.

Both 4X4's

BADA$$69 · 01-06-2004, 12:02 PM

350/700R4/3.08 and I get about 12-13 MPG but I can't use the overdrive around town because in overdrive the engine only turns 1000rpm at 55mph. I haven't check the mileage on the highway yet. I need to get a 3.73.

8.1PWR · 01-06-2004, 12:59 PM

350 4bbl 4spd 4.10 rear. I get about 10mpg. Without an overdrive I'm turning some rpms on the freeway. I'm thinking of putting a 700R4 in the truck to get overdrive.

miket · 01-06-2004, 01:04 PM

3.0's and a ZZ502=no gas mileage.

Ackattack · 01-06-2004, 01:25 PM

Working on it:
Was getting 10.4 on the highway, working on the carb and timing last trip I got 12.6. I'm hoping for 14, but my tires are too short I think. I'm running 295/50/15 now. Will be running 275/50/17s by summer hopefully. See sig for engine/drivetrain combo

1-PU70 · 01-06-2004, 02:03 PM

402 - 700R4 - 3:73posi - 31's
13.5mpg towing around 4500lbs.

Willy Prost · 01-06-2004, 02:13 PM

Shortbed/ stepside/ 250 6cyl/ Tremec 3550 5-speed/ 3.73 gears/ 235-75-15 tires
15-17mpg around town
18-21mpg highway

SWEET7T · 01-06-2004, 05:38 PM

327/350/3.08 I have 255-70/R15 Around town I will get ~13. On the interstate running 75-80 (2800-3000rpm) I will, once again, get ~13.
If I do like 55 or so and keep my engine down at like 2300, then my mileage climbs ( but who wants to go that slow

jku72 · 01-07-2004, 09:21 PM

68 C10 burb, 350, 4 speed, 3.07 rear, 31" tires, 18-19 mpg highway, 15-16 locally.

breeh · 01-07-2004, 09:54 PM

K10, 427 with a 700R4, 4:10 axles with 33" rubber. 9 mpg in a headwind, with a tailwind, uphill, and downhill.

*1972C10* · 01-07-2004, 10:49 PM

1972 C10 355 10.-1 3.73s 276/50r15 tires Gets about 2300 at 50 and 3300 at 70 its a miracle to bust 10mpg

1974StepSide · 01-07-2004, 11:13 PM

350 cid, Turbo 400, 3.08's in the rear, lead foot = about 11-12 mpg...

71chevylongbed · 01-07-2004, 11:32 PM

with a 350/TH350 3.73 gears and 26 inch tall tires i get around 8-9 taking it easy. i don't want to know what it gets when i put my foot into it. but who cares about gas mileage when you got power!

jewels. · 01-08-2004, 12:09 AM

350
3 speed stock tranny
3.73 gears
255/60/R15 tires
2bbl carb

12-13 mpg in town
18-19 mpg highway

i think that might be outperforming some of the new SUVs out there!

jewels.

jorgensensc · 01-08-2004, 01:18 AM

1972 step 383/350/3.08 (I think)
10 mpg city, 13 highway running 75-80 at 4000RPMs

and yes jewels you are, Our 2002 Dodge Durango with 5.9 and auto only got 12-13 highway. My wifes new 2003 audi a4 quattro with 3.0 only gets about 18-21mpg, but I have a lead foot!!

1969 GMC · 01-08-2004, 01:37 AM

I still have a bunch of question marks. I don't drive crazy like alot of people here do, I only go to about 2500 rpm and thats it. According to the p/o, the original 4.10's were swapped for 3.73's.
'73 stock 350, SM465, 3/4 ton 4x4...and I swear that I can get close to 18 on long highway trips, If I keep my foot out of it (which I usually do). But, since I never go on long highway trips in my truck, I never get that good of gas mileage. I'd guess 14 or 14 on the highway to and from work and school, and around 10 in town.

Here's how much of a grandpa driver I am- I consider opening the Qjet's secondaries a special occasion, that rarely happens.

rn2fine · 01-08-2004, 02:08 AM

1972 Suburban C10 2wd, late model 350, edelbrock carb, vortec heads, headers, TH700, 3.07 gears, mostly highway with some city driving, 14.7 mpg

500HP/SB · 01-08-2004, 02:12 AM

'70 k10 350/sm465 35inch tires dual quads= i dont want to know
probly 5-10mpg

01-06-2004, 04:24 AM	#1
magoo72 Registered User Join Date: Jan 2003 Location: minden la Posts: 114	gears and gas milage/whatcha got? what gear in the rear is the popular for gas milage ,what tranny is the favorite of my fellow truckers. i run a 350/350turbo with 3.73 gears ,its allright for back and forth to work and local drivin and will snatch your head back into the rear window !!! but........... if i do have to get on the interstate it sounds like i am running @ Daytona. and the gas gauge falls rather quickly$$ i am building a new rear end w/3.08 gears,hoping not to sacrifice my boogidy,bogidy for better milage. lemme know what yur running and how good is your milage/ btw i get bout 10 miles to the gal. mr magoo

01-06-2004, 09:17 AM	#2
JIMs70GMC user # 2756 Join Date: Jun 2001 Location: Chesapeake, Virginia Posts: 4,612	4.10s, 33" tires, 8-9MPG stock 350 running a little rich. __________________ 1970 K25, 8' stepside bed 350/465/205 44 up front, 60 in the rear 4.10s rolling on 33" Dunlop MTs 1986 K5, 350/465/208 Dana 60/14 bolt from a cucv 36" Super Swampers TSL/SX 1983 K20 w/ CUCV axles, 350/700R4/208 sitting on 37" Goodyears 1986 M1031 6.2 diesel, TH400/NP205 locker in the rear and a LS in the front, all stock for now..... 1986 K30, 350/400/205 dana 60 and 14 bolt. I kept the drivetrain. Body/bad and chassis are gone. 1981 K30, 350/465/205 dana 60 and dually 14 bolt. Has a G80, and a flat bed. Going to replace the flat bed. 1985 K20, 350/400/208 10 bolt and SF 14 bolt. I wonder where I can find some 1 tons. Hmmmmm

01-06-2004, 09:20 AM	#3
mrein3 Registered User Join Date: Feb 2000 Location: Center City, MN, USA Posts: 3,254	3.73 gears. 350/th350. 9.5 mpg most of the time towing my boat. 13 mpg was my best ever. That was not towing and I had a good tail wind. __________________ '70 cab, '71 chassis, 383, TH350, NP205. '71 Malibu convertible '72 Malibu hard top Center City, MN

01-06-2004, 10:33 AM	#4
cdowns Senior Member Join Date: Jan 2003 Location: daytonabeach Posts: 22,956	4:10/200R4/275:60X15tires and i git 16.5mpg running 70-75 on the highway about 10-11 around town __________________ 71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF DONT BELIEVE EVERYTHING YOU THINK TAKE MY ADVISE;I DON'T USE IT ANYWAY

01-06-2004, 10:41 AM	#5
lukecp Formerly yellow72custom Join Date: May 2001 Location: Austin, TX Posts: 7,531	350/TH350/3.07. Usually around 12-13mpg on premium fuel...but my motor is built a little and i have a lead foot. __________________ '72 Chevy C10 Mild 350/TH350/3.07. Ochre/White. Old high school ride. '70 GMC C2500 '62 327 4bbl/SM465/4.56-geared Dana 60. White/White. Project or parts truck. '97 Saturn SL DD. 1.9/5-speed. 40+ highway mpg

01-06-2004, 11:06 AM	#6
JimKshortstep4x4 Senior Member Join Date: Jul 2001 Location: Muskegon,MI,USA Posts: 6,026	My son's truck is the one we use mostly and it has a 307/TH 350 with 3:07 gears. Gets 16 mpg. Jim

01-06-2004, 11:27 AM	#7
zigzag Registered User Join Date: Jan 2004 Posts: 21	327/3spd manul/4.56 gears on a 3/4 ton truck with some 8 ply mud grips.....maybe 8 MPG

01-06-2004, 11:50 AM	#8
Paul72 Registered User Join Date: Sep 2003 Location: Waterloo, IA Posts: 1,147	K/20 - 350 w/ quadrapuke, 4sp, 3.73 open, 31" tires gets 10 mpg full, empty, warm, cold, north or south. K/5 - 350 w/ 750 Holley, TH350, 3.08 open, 31" tires gets between 9-10. Both 4X4's __________________ '72 Chevy K20 - 383/4sp/205 - SOLD after 41 years in the family Next project - K/5 Tahoe (71 Blazer on 99 Tahoe chassis) Build thread: http://67-72chevytrucks.com/vboard/s...d.php?t=789958

01-06-2004, 12:02 PM	#9
BADA$$69 Walking accident Join Date: Nov 2001 Location: Laurens, SC Posts: 200	350/700R4/3.08 and I get about 12-13 MPG but I can't use the overdrive around town because in overdrive the engine only turns 1000rpm at 55mph. I haven't check the mileage on the highway yet. I need to get a 3.73. __________________ Laurens, SC 69 C10 W/350 & 700R4 89 Mustang GT

01-06-2004, 12:59 PM	#10
8.1PWR Registered User Join Date: Nov 2003 Location: Green Valley, AZ Posts: 28	350 4bbl 4spd 4.10 rear. I get about 10mpg. Without an overdrive I'm turning some rpms on the freeway. I'm thinking of putting a 700R4 in the truck to get overdrive. __________________ 1970 Chev C20, 2wd, LB, 350 4BBL, muncie 4spd, 4:10 limited slip. 2002 Chev 2500HD 8.1L Allison, 4X4. 1996 Chev S10 Blazer, 4X4. 2006 Jeep LJ Rubicon

01-06-2004, 01:04 PM	#11
miket Registered User Join Date: Jan 2003 Location: Seattle WA Posts: 1,466	3.0's and a ZZ502=no gas mileage. __________________ FocuzTech Performance Evergreen Protective Coatings Gatorhyde...the best kept secret in spray in bed lining & protection

01-06-2004, 01:25 PM	#12
Ackattack Senior Member Join Date: Aug 2002 Location: Valley Center KS Posts: 3,525	Working on it: Was getting 10.4 on the highway, working on the carb and timing last trip I got 12.6. I'm hoping for 14, but my tires are too short I think. I'm running 295/50/15 now. Will be running 275/50/17s by summer hopefully. See sig for engine/drivetrain combo __________________ Project Bruiser: 68 Pro-Touring C-10 5.3L / 4L60E Project Ironhide: 97 GMC Crew Cab 4x4 Cummins SOLD: '69 GMC 1/2T SWB TBI'd: Project No Buck Assembly Manual Index Sign up Thread!!! Factory Service Manual Index

01-06-2004, 02:03 PM	#13
1-PU70 Registered User Join Date: Apr 2000 Location: Bradenton, FL Posts: 1,036	402 - 700R4 - 3:73posi - 31's 13.5mpg towing around 4500lbs. __________________ 1970 CST/10 402,700R4,3:73 posi,AC,PS,PB,TLT,PW,Buckets with heaters

01-06-2004, 02:13 PM	#14
Willy Prost Senior Member Join Date: Jan 2000 Location: Arlington, VA Posts: 398	Shortbed/ stepside/ 250 6cyl/ Tremec 3550 5-speed/ 3.73 gears/ 235-75-15 tires 15-17mpg around town 18-21mpg highway

01-06-2004, 05:38 PM	#15
SWEET7T Try spinnin 4 rear tars Join Date: Sep 2003 Location: Salt Lake City, Utah Posts: 757	327/350/3.08 I have 255-70/R15 Around town I will get ~13. On the interstate running 75-80 (2800-3000rpm) I will, once again, get ~13. If I do like 55 or so and keep my engine down at like 2300, then my mileage climbs ( but who wants to go that slow __________________ SWEET7T 1970 C10, 2wd, LB, 307/TH350/3.08. PS, PB



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01-07-2004, 09:21 PM	#16
jku72 Registered User Join Date: Jan 2002 Location: cornville, maine Posts: 659	68 C10 burb, 350, 4 speed, 3.07 rear, 31" tires, 18-19 mpg highway, 15-16 locally. __________________ jku Cornville, Maine 68 C10 burb 42 Willys MB 46 Dodge WF-32 1.5 ton 53 & 56 Olds' 60 Cadillac 22 Dodge Brothers

01-07-2004, 09:54 PM	#17
breeh Recovering 67-72 Addict Join Date: Oct 2000 Location: North Bend, WA Posts: 1,788	K10, 427 with a 700R4, 4:10 axles with 33" rubber. 9 mpg in a headwind, with a tailwind, uphill, and downhill. __________________ 68 Short Fleet 4x4; 427; BTO Level 3 700R4; NP205; Dana 60 front and rear; 4" lift with 35's; Disc brakes; AGR variable ratio steering; factory bucket seats; factory tach and tilt. "Friends call me cruzer cuz I like fast cars and fast women"

01-07-2004, 10:49 PM	#18
1972C10 Account Suspended Join Date: Dec 2003 Location: Texas Posts: 2,686	1972 C10 355 10.-1 3.73s 276/50r15 tires Gets about 2300 at 50 and 3300 at 70 its a miracle to bust 10mpg

01-07-2004, 11:13 PM	#19
1974StepSide Play it Loud... Join Date: Aug 2002 Location: East San Jose, CA Posts: 465	350 cid, Turbo 400, 3.08's in the rear, lead foot = about 11-12 mpg... __________________ Big Moe =-=-=-= 1974 Cheyenne Super Stepside, 350/400, Hooker Headers, Flowmaster Mufflers... Needs new doors, fenders, hood, and paint. 1952 Chevy Pickup waiting to be brought back home!

01-07-2004, 11:32 PM	#20
71chevylongbed Got Horsepower? Join Date: Sep 2003 Location: IDAHO Posts: 406	with a 350/TH350 3.73 gears and 26 inch tall tires i get around 8-9 taking it easy. i don't want to know what it gets when i put my foot into it. but who cares about gas mileage when you got power! __________________ 2001 Dodge 2500 Cummins, 4 inch lift, 35" Toyo MT's on Ultra wheels, P-Pump Conversion, AFE intake, Fass, 5 inch exhaust, Pyro,Boost,and Fuel pressure guages, and a whole bunch of other stuff "The Money Pit" SOLD-71 Chevy C10 long bed- 2/4 drop-- 350,th400, Edelbrock performer RPM intake,Edelbrock 600 CFM carb,Crower 240 cam,port and polish,Dynomax headers,HEI ignition,dual 2.5 inch exhaust with Flowmaster 50 series mufflers

01-08-2004, 12:09 AM	#21
jewels. Registered User Join Date: Jul 2001 Location: Munster, IN Posts: 1,100	350 3 speed stock tranny 3.73 gears 255/60/R15 tires 2bbl carb 12-13 mpg in town 18-19 mpg highway i think that might be outperforming some of the new SUVs out there! jewels. __________________ 68 C10 Red Step 350 my first child & main focus 58 3200 Apache LWB Step the upcoming project

01-08-2004, 01:18 AM	#22
jorgensensc Registered User Join Date: Jul 2003 Location: Cypress, Tx Posts: 4,005	1972 step 383/350/3.08 (I think) 10 mpg city, 13 highway running 75-80 at 4000RPMs and yes jewels you are, Our 2002 Dodge Durango with 5.9 and auto only got 12-13 highway. My wifes new 2003 audi a4 quattro with 3.0 only gets about 18-21mpg, but I have a lead foot!! __________________ 1972 C20 Suburban- Big Blue Betty '56 Chevy Bel Air Sedan- Frame up Restoration -What would you attempt to achieve if you knew you could not fail?- -I Refuse To Tiptoe Through Life, Only To Arrive Safely At Death's Door- R.I.P. EAST SIDE LOW LIFE

01-08-2004, 01:37 AM	#23
1969 GMC Registered User Join Date: Feb 2003 Location: The Rubber City Posts: 5,498	I still have a bunch of question marks. I don't drive crazy like alot of people here do, I only go to about 2500 rpm and thats it. According to the p/o, the original 4.10's were swapped for 3.73's. '73 stock 350, SM465, 3/4 ton 4x4...and I swear that I can get close to 18 on long highway trips, If I keep my foot out of it (which I usually do). But, since I never go on long highway trips in my truck, I never get that good of gas mileage. I'd guess 14 or 14 on the highway to and from work and school, and around 10 in town. Here's how much of a grandpa driver I am- I consider opening the Qjet's secondaries a special occasion, that rarely happens. __________________ 1969 GMC K2500 1996 Honda Accord 2007 Kawasaki KLR 650

01-08-2004, 02:08 AM	#24
rn2fine Registered User Join Date: Jan 2004 Location: Arizona Posts: 157	Mileage 1972 Suburban C10 2wd, late model 350, edelbrock carb, vortec heads, headers, TH700, 3.07 gears, mostly highway with some city driving, 14.7 mpg

01-08-2004, 02:12 AM	#25
500HP/SB please don't break Join Date: Sep 2003 Location: southern california Posts: 173	'70 k10 350/sm465 35inch tires dual quads= i dont want to know probly 5-10mpg __________________ 70 k10 35s 350/sm465/np205 titanspeed.com

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