Just hit a new best of 32MPG with my 5.3

KARNUT · June 29, 2023

8 minutes ago, BB68 said:

Mine was 3.55s and that trip was a mix of 60 and 70 mph. Also mind you that was back before our gas went to sheet with our base gas still at 87 octane and one of additives being banned by epa

All my trucks were modified with at least a hand held tune requiring premium fuel. Along with modified induction and exhaust. Before the mid eighties high rise intakes, headers sometimes cams. They were so lame HP wise, we would go through them. Being much younger all nighters for performance was common. That would include my brothers and even my father.

Jworks · June 29, 2023

On 6/26/2023 at 11:09 AM, SC4R3C120W said:

I'm in the 3.0 diesel and commute 120 miles. Here's my 400mi mpg average with best listed.

I've never gotten anywhere close to that. 22 was my best -- 500 mile round trip. You must be driving very flat terrain. What oil do you use?

BIGDOGx · June 29, 2023

53 minutes ago, Jworks said:

I've never gotten anywhere close to that. 22 was my best -- 500 mile round trip. You must be driving very flat terrain. What oil do you use?

Yeah i can only laugh at some of the estimate mileage ratings from people here and not a chance is either a 5.3 or 6.2 getting 30 mpg, not unless you are driving down a mountain.

Wiggums · June 29, 2023

Beg to differ. My overall MPG out of the computer has been consistent with hand calculation.

And 30 mpg with a 3.0 diesel is a lot more common, obviously, than a 5.3 V8. I averaged at around 23 mpg.

Now, if I were to do a 400 mile trip completely on the highway, without stopping, I can do it.

The way it is, I drive 48 miles on the highway and it gets 30 mpg. Then I drive two miles uphill to my house, it's a killer so I watch the average drop down to 25. It sucks.

BB68 · June 29, 2023

5 hours ago, KARNUT said:

All my trucks were modified with at least a hand held tune requiring premium fuel. Along with modified induction and exhaust. Before the mid eighties high rise intakes, headers sometimes cams. They were so lame HP wise, we would go through them. Being much younger all nighters for performance was common. That would include my brothers and even my father.

Our 70's 80's 454s received 60's 396 cast iron intakes($40 swapmeet items) a mild cam, and dual glass pack exhaust. results in +4 mpg on them with about 425hp 500lbs torque. very fun vehicles after that. btw we would reuse the factory Qjet

KARNUT · June 29, 2023

17 minutes ago, BB68 said:

Our 70's 80's 454s received 60's 396 cast iron intakes($40 swapmeet items) a mild cam, and dual glass pack exhaust. results in +4 mpg on them with about 425hp 500lbs torque. very fun vehicles after that. btw we would reuse the factory Qjet

My 92 Chevy lowered truck engine.

KARNUT · June 29, 2023

Just now, KARNUT said:

My 92 Chevy lowered truck engine.

redwngr · June 29, 2023

On 6/28/2023 at 3:16 PM, Luc1f3r said:

LOL what are yall doing, drafting big rigs to get these numbers?

Best ive done on a long trip is 20.

19 at4 with 6.2 and 35s.

My pic is from an LZO.

Previous was an LM2 that got a little over 26 mpg across 36,000 miles.

Running 55 - 60 it would get the 25 mile page over to low-mid 30's any day on level ground, no wind, not drafting.

64BAwagon · June 29, 2023

There are 2 things that guys will exaggerate measuring, one of them is mileage.

KARNUT · June 30, 2023

People get confused in thinking that it’s the measurement problem or miss calculation. Actually it’s the drive. Slow and steady up to speed will net the best results. Allowing ample time to reach your destination.

redwngr · June 30, 2023

Wiggums · June 30, 2023

This is one thing I miss about my Chevrolet.. my Ford F-150 with PowerBoost gets 26 on the highway.

That's because the PowerBoost doesn't have cylinder deactivation...

With the Chevy, it could go down to one cylinder (about 50 hp, right?). 50 hp provides sufficient power as long as I am very easy on the gas, going a steady 60 mph, on a very flat surface.

Edited June 30, 2023 by Wiggums

SC4R3C120W · June 30, 2023

On 6/29/2023 at 12:49 PM, Jworks said:

I've never gotten anywhere close to that. 22 was my best -- 500 mile round trip. You must be driving very flat terrain. What oil do you use?

I use the ACDelco 0-20W that we're supposed to use. Change oil every 5k miles. I typically put on cruise control at 60-65mpg in the morning to work when there's no traffic. If i kept to 55mph, i've seen 40mpg no problem (mostly level ground in Los Angeles). on the way home, it's literally stop and go for 2.5 hours, and i still see the 30mpg average.

BTW, i'm in a RST that i put a 3.5" RC lift (top spacer), new UCA, and a 2.5" block in rear. I changed tires from 265/65/18 (31.5" tall) to 275/70/18 (33" tall). Last, i did the resonator delete and a new hose from the air box to turbo inlet tube. I can't get a CAI in California becasuse of emissions, but if i could change anything else, it would be the turbo inlet tube that comes with the S&B CAI system. From what i've seen, the bigger box and filter actually loses power and pedal response. But unfortunately, they don't sell just the tube, and it's not California legal.

Edited June 30, 2023 by SC4R3C120W

SC4R3C120W · June 30, 2023

here's some older pics showing mileage has been consistent.... the onscreen numbers where actually less than what my calculations were.

June 30, 2023

20 hours ago, 64BAwagon said:

There are 2 things that guys will exaggerate measuring, one of them is mileage.

Ummm, are you claiming people are photoshopping their pics here for internet points? That doesn't even make sense.

The reason some are getting atrocious mileage is due to having 35" tires, and/or lifts. My best (6.2) 50 mile is about 32.3, but this was a very downhill route on a two lane road. Not something I expect to see again. My normal "400 mile" is pretty consistent at about 23-24 under normal "hwy" driving. I have a high country with all seasons. I don't have AT's, which also murder mileage.