Useless Information

[Tonyrodz]

My 03 isn't flex fuel, so I guess no e85 for me.

 

[Tozan]

I have 4.10 gearing with 34.6 inch tires and a 4 inch lift.

I just drove from Reno to Huntington Beach, my over all average is 16.8 MPG after 3 tanks of fuel mostly highway with about a 100 miles of city driving.

On my first tank with regular grade fuel with 0% alcohol I averaged 18.3 MPG up and down mountains.

The last two tanks had 10% alcohol in the fuel and the average dropped down to 15.6 mostly on flat ground and lower altitudes.

Return trip:
I will be switching from my economy regular fuel tune to a 93 octane high performance tune and running 10% alcohol on the return trip. I will also be driving at high desert altitudes (4000 to 5000 feet)

 

[swathdiver]

Notice: Some additives are not compatible with E-85 fuel and may harm your fuel system. Damage caused by additives would not be covered by your new vehicle warranty. Do not use additives with E-85 fuel.​

Thanks for the reminder! I'll not use those little bottles until back on 93.​

I have 4.10 gearing with 34.6 inch tires and a 4 inch lift.

I just drove from Reno to Huntington Beach, my over all average is 16.8 MPG after 3 tanks of fuel mostly highway with about a 100 miles of city driving.

On my first tank with regular grade fuel with 0% alcohol I averaged 18.3 MPG up and down mountains.

The last two tanks had 10% alcohol in the fuel and the average dropped down to 15.6 mostly of flat ground.

Return trip:
I will be switching from my economy regular fuel tune to a 93 octane high performance tune and running 10% alcohol on the return trip.

Looking forward to your results former neighbor!

 

[Tozan]

I drove the eastern Sierras high desert plains 4000 to 5000 feet altitude on my return trip driving hwy 14 and route 395.

The over all average was 16.6 mpg on the return trip.

In the flat areas I was averaging 18+ mpg.

In the mountainous areas the average was about 14 mpg.

All total for the entire trip both directions.
1385 miles
85 gal fuel
16.3 mpg average

Pretty good for going from 5000 feet to 8000 feet then sea level and back to 8000 then back to 5000 feet. So a lot of mountain driving and a lot of somewhat flat ground. In one direction the flat ground was low altitude and the return trip high altitude.

I noticed it does the best around 1700 rpm so my gearing is still a little deep for best fuel economy however it pulls great and going from 60 to 90 mph takes only seconds at full throttle. When I get new tires (at least year from now) I will get something a little taller maybe 35 or 36 and the gearing should be perfect for fuel economy.

 

[swathdiver]

One of our daughters is taking her driving test Friday so this afternoon we headed out for some more practice parking. This dropped that particular tank's average economy down to 11.30 on E85. After fueling we hit the highway and took some notes. At 65 mph the truck got 16 mpg, 70 mph about 15 mpg and 75 mph gave us 14.5 mpg, all on E85.

2008 and 2010 models of the GMC Yukon XL 4WD show both getting 11 City and 14 Hwy on E85. The former with a 4-speed transmission, the latter with the 6-speed and VVT added to the engine and a different camshaft profile. There is no official published MPG for 2009 trucks in the GMC brochures or even my particular truck on fueleconomy.gov. My window sticker with regards to fuel economy is blank. You know who was President then. Anyway, this thing is getting regular mileage on E85 but not on 93.

 

[swathdiver]

When my daughter and I concluded our driving test practice the other night, after refueling and returning home we were at 14.3 mpg. My lovely wife borrowed the truck today and returned it averaging about 9 mpg! She said it was too much fun driving it, the truck just wanted to keep going faster and faster and she liked the engine sounds it made every time she took off! LOL

Ohh, something else I forgot to mention earlier. Did some more poking around about spark plugs and came across some posts where fellas mentioned degraded fuel economy with the new 41-110s versus the 41-985s that their trucks originally came with. No misfires, no noticeable loss of power, just a slow and steady decline in fuel economy after about 20-30k miles with the new plugs. The gap issue is not relevant is these instances either.

So having said that, this reminded me of the experimenting with plugs we did back in the day with our race cars. They didn't misfire or have a noticeable loss of power but when I switched from the factory plug to the then new NGK Splitfires ( I think that's what they were called) the cars picked up about 5 horsepower but lost 3 miles to the gallon in economy.

One other thing some of the men mentioned above had in common was factory K&N air filters. Many people swear the oil coats the MAFs and kills performance. My experience has been the opposite. However, I've never seen the same mileage as the truck did when it had the paper air filter and those Load Range E tires, 17-18 @ 80 mph for 700 miles.

My little helper is turning into young lady, getting her driver's license today and not so sure she'll be around to help old dad with the truck anymore! Time to train up number 3!

Not totally useless information, well, maybe.

 

[PG01]

Some more useless info for you guys....
@swathdiver @iamdub

Long drive yesterday, got in truck loaded up wif and kids to south jersey, to see my father who sadly, is dying...anyway got in truck had 1/4 of a tank and was at 11.3......wife drove last hence the lower economy and no gas.....i fill it up with sunoco 93 got on the road. 2.5 hr drive and had it up to 19.3 @73 mph , seemed to be the # that it wouldn’t drop or go up anymore and as i got closer to my destination more traffic less highway shut it off @18.5. Got in the truck 3 hrs later and started to next destination, Rockefeller center NYC. Lots of traffic to the outerbridge crossing, through staten island ( @Kenny D i was looking for ‘LARRY!!!’ My kids were cracking up as i had the window open yelling LARRY), over the verrazano into Brooklyn, by Barclay center, up the BQE, into queens through the Brooklyn-Battery tunnel into lower Manhattan past World Trade Center Memorial and 1 World Trade up the West Side Highway to midtown, cut across in the 50’s parked the truck on 54 and Ave of the Americas and was at 15.5 on the dic. Used the bathroom in the Hilton, walked up to St. Patricks Cathedral, lit a fews candles, prayed for all you heathens....lol just kidding... did sit there for 1/2 hr and headed to see the Rockefeller tree. Walked around took a bunch of pics, went to lego store, dropped some money in there, went into saks 5th ave, more money, watched the light show outside and window displays, American girl doll store, more moolah, hit the Hilton b-room again and headed home up west side highway into westchester (yonkers) across Tappen Zee (@Cattivo ) up the NYS thruway back to good ol’ Montgomery. Gassed up because now at 1/4 tank and took 21.39 gals, highest dic went was 16.8 on trip home, 16.5 at gas station) whole trip was 346.4 miles(which according to my math is 16.1 mpg). Truck turned 61k and ran like a champ all day, trans temp kept between 99-115, ambient temp was 6-14, brrr, oil press @ just under 40 psi and temp right at 210. One thing I noticed is a slight whine from ds front (everyone fell asleep and no radio) sounds like hub but I will investigate further today or tomorrow. Good day, trip and time over all. My father is half man he ever was and it’s killing me, but he lived his life and he will be with my mother which is how it should have been for the last 23 yrs.

Happy New Year fellas.

 

[swathdiver]

Thanks for sharing Pete! It's been 18 years since my wife and I spent Christmas in New York. She's from the Bronx and was just saying it was time to spend Christmas up there again with family. Sorry to hear about your father. Mine are getting on in age, in the last three years we lost three uncles. My wife and I try to be very accomodating with regards to our children spending time with our folks so they'll remember them, learn from them, and know why we are who we are and give them a chance to pass down traditions and recipes and such.

 

[Tozan]

got any ideas for brake upgrades? any brands to stay away from?

I installed a set of EBC front rotors and a set of yellow pads on both ends. With my larger heavier tires the braking had gotten softer but, after I up graded to these pads the braking improved to better than before. I highly recommend the Yellow pads.

 

[Tozan]

Hey James I read you needed a tire winch if the 2011 Tahoe part will fit yours I have one I removed from mine you can have it....

Also if you want to raise and level your unit. I have a never used CCM level lift kit I need to sell. It is Part number CCM071500-SUV it is supposed to fit 2007 up.

If you want both I would like $130.00 plus what ever shipping will cost.

Also I was wondering what size tires are you running? I also have let mine idle and it tends to kill my millage when I do that.

 

[swathdiver]

Thanks for the offer Charles, if I don't fix my hoist I'll look you up. Going with the RC 2" level, maybe.

This last tank of E85 we got 9.5 mpg average. Been enjoying the power, my wife even more, so it cost $.24 cents a mile to drive this time around. Bumped the tires to 50 psi last week too.

That P0430 is showing up near everyday now but no time to work on it. I hope those bolts and studs and nuts up there aren't rotted!

With a little free time today before a trip to the dentist I took her out on the highway to get an mpg profile at different speeds. Ran into torrential rains so it was a bust. However, after two minutes at 75 mph, the average mpgs were in mid 14s and upon entering the torrential storm the mpgs dropped off over a mile per gallon. Just driving on a wet road it lost near .5 mpgs and got worse barreling through that nasty storm.

The KO2s like the Radital T/As of my racing days were rock solid in the rain, the truck did not budge one iota.

 

[Jason_S]

You sound to be having a better experience with E85 than my Tahoe did. I gave it a steady diet of E85 in the summer of 2014 for about 5 tankfuls. My E85 fuel costs were comparable to running premium. After three or four tanks, I thought my fuel pump was on its way out as it had gotten way down on power and was very difficult to start. It was suggested that I switch back to premium for a bit, since that should give me a little more time to get it in to the shop and get the work done. By the time I had finished the first full tank of premium, it was pack to running perfectly and starting on the first try. It pulled a little Imprezza (and a spare subie engine) through the hills of West VA and half way across the country to the land of corn before I had the time and a driveway to service the fuel system. Oddly, here in the land of corn, I can't find E85 without going more than 30 minutes out of my way, in spite of driving past at least one ethanol plant every day. The Suburban doesn't do flex fuel, so I don't give e85 much thought any more.

As long as the KO2s weren't near bald, the Jeep loved them for everything except mud. They always seemed a bit short wearing though.

 

[swathdiver]

Sounds like your Fuel Trims also got out of whack Jason. I've been having trouble with the cat on the right side, it has got to be the gas mileage culprit. Curiously, while I can get nowhere the mileage I'm supposed to on gasoline, it's pretty close on E85.

I'm gleaning from reading many posts across the web, it seems those who run the KO2s with too little air are not getting the mileage out of them. Those running them higher get more life out of them. Running them in the 30s my expected life was barely 40k miles. Once I bumped them up into the 40s they did not lose any appreciable rubber and now have them at 50 psi. I'll be happy if they make it to 55-60k miles.

 

[swathdiver]

Last two tanks of E85 @ 71% average just over 10 mpg in city driving. Average speed about 19 mph. After fueling and picking up the kids, found out one was staying late for some math help so we headed for a road I'd been wanting to check out for some time and see the farms and homes along it. Anyhow, at 60 mph the truck averaged 14.2 mpg and in the 13s down to 50 mph. Any slower and the mpgs dropped. Didn't do too bad idling either which is something I've started to notice.

Even though prices are going up even for E85, this motor just loves it.

In other news I was able to contact the two previous dealerships that serviced the truck. The first one, Opequon Motors, serviced it until 2013 and the only significant thing they did was replace 7 tire sensors and do the front brakes and turn the front rotors. The second dealer, Strosnider Chevrolet, had the truck brought to them in 2016 with 110K on the clock with AFM problems. They replaced all 16 lifters, the latest and improved VLOM and put in the new left side valve cover. The AFM lifters are the latest Delphi II De-Ac lifters, 12645725.

So now knowing that the motor is fresh with all the improved parts, do I turn AFM back on or leave it off? If I leave it off, do I proceed with my plans to remove AFM completely from the motor or put that money towards my wife's replacement vehicle and do this later on down the road?

Oh, did the chalk test on the tires, LR and RF after about 100 yards (now at 50psi):

 

[swathdiver]

The Carfax for this truck showed 4 prior owners. Don't think so. The original owner is listed as two owners. Then it was shown as leased for two days and then I'm confused. From what I gather, the first owner bought it from Opequon new in 2009 and traded it in to the same place in April of 2016 with 110k. The third owner is shown to have owned it for two days and Strosnider is shown under the same ownership as putting on new tires and then checking the engine in May 2016 with the same mileage as the repair work done in December. The owner is listed as Strosnider but the repair records show Manheim as the customer. Strosnider kept the truck until February '17 and 111K, someone was driving it around. Then it went to auction once again and Certified Auto Direct picked it up and I bought it from them out of Winston-Salem, North Carolina. Maybe that two day 3rd owner had the AFM crap out on them and they took it back and got another vehicle or their money back?

Curiousities but ultimately like the title says, useless information.

Ohh, that chalk test mean anything other than what looks to me to be even wear???

 

[PG01]

Reading all the horror stories i would leave afm off and still plan on deleting it, in the future.
Tires look even to me.
My 2 c

 

[Tozan]

I have been running NON ethanol gas lately... I love it I am running at 4400 feet elevation most of the time and on mostly flat ground at 50 mph I was getting 20.1 mpg and at 65mph I was getting 18.6 mpg Pretty big jump from my normal 16.5

On the interstate running 80 to 85 it dropped down to 16.1 while going up and down some pretty big hills here in Utah. FYI speed limit on the interstate is 80 MPH.

 

[swathdiver]

Switched over to Mobil 93 in preparation for resetting the fuel trims and replacing the cats. Averaged 13 mpg and alcohol content was down to 17%. After filling up, I saw a high of 17.3 mpg on a drive with my wife but pulled into the driveway with 15.4 mpg.

Both cats have thrown codes now. On E85 the right cat would throw codes every time I took the truck out. On pump gas it takes a couple days. Y-pipe will get replaced first and then the O2 sensors if needs be.

Both Coax cables are also throwing codes. One for XM/Sirius Onstar and the other for the Digital Radio Receiver. Weird. The former pops up every so often the latter is a first time. FM radio reception is noticeably degraded. Sirius and car phone are fine. Not wanting to drop the headliner, I'll take that job to the dealer.

Magnaflow system is scheduled to arrive on Wednesday and hope to knock it out next Saturday, health and weather permitting.

Charles, I remember losing about 2mpgs when they started putting ethanol in our gasoline. My vans went from 25 to 23 on the highway. I remember too when oxygenated fuels was all the rage and while I do not remember the effect it had on mileage, I do remember it making our motors knock a lot more and having to reduce our boost pressure until we used additives or race gas. Do they even do that crap anymore?

Kids are growing up too fast. Our oldest is giving birth to our first grandchild next month, #2 just got her first car and last night had her first real job and #3, our baby, has lost her baby voice and is turning into a teenager. Our girls are growing up too fast. While they whined and moaned, their tutelage on working on cars is paying off. The oldest knows more about cars than her husband! She's done oil changes, changed air shocks, a hub and brakes and can plug tires. She's still somehow incredibly ******* tires though! That girl can run through a set of 4 faster than Tom Cruise at Daytona! Well, that's HIS problem now! hehehe

 

[PG01]

Funny, if im driving all weekend whenever i pull that truck into garage minimum mpg is at 15.5-16 and its only around town, minimal highway, if i do more highway i have it up to 18-19. But, whenever i get in and seat is all the way up (which means the wife has been driving) its always at high 12’s low 13’s.. man shes got a heavy foot...

 

[swathdiver]

Mine too! I got in once at it was at 8mpg! She said she liked the get up and go after the BlackBear tune. I averaged 13.0 mpg but had she not borrowed it earlier in the day it would have been almost 14! LOL

When we had just one auto, I would always best her mpgs by about 4. She drives a lot faster than I do, brakes later and takes off faster. Not bad mind you, just not as efficient. I'm perfectly comfortable with her behind the wheel. My sister on the other hand, she's a nut behind the wheel! Drives like I did at 16! Ohh and one my aunts, she's even crazier! When I was a kid I had to follow behind her for some reason. 25 mph in a 45. Then up to 55, back down to 40, then up to 60, she was all over the place. Thirty years later no difference! I'm the convoy leader or we just agree to meet at a certain time and make our own way.