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k5 MPG?

A

Artemis Entreri

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Just out of curiosity, what kind of MPG do these trucks get?

I'm looking for a K5, lifted, say, 35inch tires? Assuming I get a 350 what kind of mpg should I be looking at?

What if I find a 305?

How bad is the power difference between the 350 and 305? How much will the rest of the drivetrain stand up if a bigger 350 is put in later?

Thanks
-Steve-
 
With 35" tires and 4.56 gears and 8" lift with a 240K mile engine i was getting 8.5 MPG around town, if i did some hiway driving then i could get 9.5-10 MPG. When my rig was stock i could get 14 on the hiway. Most of my driving is around town though.
 
Diesel K5's are the only ones that'll get any kind of mileage you want to hear about. A stock 6.2 diesel K5 with 700R-4 will pull down mid 20's on the highway and 15-18 in town. Power is on par with a mid 80's 350...

Rene
 
Yeah. If you can get 13mpg out of a K5 with a small block V8, OD, and appropriately geared for the size tires it runs you're doing good for around town work.

Diesel is the way to go. My 1 ton pickup gets 15mpg ish without OD and pushing 130-lb 38" tires!
 
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1984 stock

running a stock 305 with 235/75/15 tires (yea i know, small but the tread is still very good:D) all highway 19.65 MPG, avg, 65 to 70 mph on average. gears are a 3.07, i think:confused: around town driving maybe 14 MPG. this was before the k&n filter and Edelbrock tubular exhaust system. i only do about one all highway run a year. This is NOT my DD but maybe once or twice a month week-end truck. AT over $3.00 a gallon i am stuck with my honda civic:rolleyes:
 
Mixed between city and highway, I think I'm getting 14-16, based on some rough figuring while I drove away from the pump.
I have a Sonoma for general transport... so I don't need quite as big a fortune yet.


Ah, yeah. Forgot...
'87 K5, 32" BFG ATs, 5.7 TBI, Apple Red and Doeskin Tan.
 
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On 37s, no OD with a slightly uped 350 mine might get 13 on the highway, and 8-10 in town. They just are mpg mobiles
 
I am easily able to get 6 - 7 MPG on the highway!!! :waytogo:

(or)

About $35/hour on the highway.
 
I get 8mpg city and not much better highway. That is with 31's at stock hight, 350 in front of a 350. Duno what gears but they are high.
 
That all sucks to hear, haha. What I expected, but not what I wanted to hear. I wouldnt mind getting a diseal, but dis here(ny) is like $4.50 a gallon, lol so I dont know if id even be saving any money getting 20 mpg with it. Plus, I dont know how much different a diseal engine is, but I know really nothing about them compared to a gas engine.

How is the power of the soc 6.2s or 350s? Can you pass people, or do you need to put your foot down and gain speed before trying it?
 
It's not an economy thing. All of these trucks are gas hogs and won't get great gas mileage. However the diesels get very good gas mileage for what they are.

The diesels, when geared correctly, aren't bad at all. However remember a lot of these trucks came with 3.08 highway gears and nothing is fast with those gears. Meanwhile they're all from the day when 200hp was a lot so don't expect it to move like a modern pickup with 300+ hp under the right foot.
 
anyone w/ old gas V8s in this thread saying they're getting high teens and low 20's [hiway or not] better rethink their math skills.

My sunfire w/ a 4 banger averages about 20mpg town/hiway mix.
 
My Suburban gets a solid 12 MPG in town and short congested highway trips.. I imagine I'll see 15 just straight cruising on the highway in OD. The TBI K5's should get 13-14 around town..
 
I can see it. Provided the engine was in good shape, the truck was stock(ish), geared correctly for the tires, and the driver was driving it sedately.

My '92 Blazer K1500 would do 13mpg all day when it was bone stock with a 350 TBI, TH700R4, 3.73's, and 32's. A bit more aerodynamic but actually heavier than the late K5's.

When I drove it from Michigan to Pensacola, FL then back to Michigan and finally from Michigan to San Diego, CA it got at least in the upper teens on those long freeway cruises at 70-75mph for hours.
 
Ben B. said:
anyone w/ old gas V8s in this thread saying they're getting high teens and low 20's [hiway or not] better rethink their math skills.

My sunfire w/ a 4 banger averages about 20mpg town/hiway mix.
Click to expand...

When I was a teen, I had an '87 Camaro with the 305 V8 and a 4-speed overdrive tranny.
A friend had a nearly identical Firebird with a v6, and IIRC, the same transmission. He got somewhere in the mid 20s on our convoy trips to Amarillo, and I usually got a solid 31 or so. He was always shocked, and tried
to keep it easy on the gas (as I already was).

Bottom line? Use enough engine, but not too much. My 305 wasn't about to win any races, but it didn't have to work hard at all.

...and, yeah. My math was good. Still is.
 
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