Mark Johnson

iTrader: (1)

Thanks guys-
well I'm committed. Just got back from trying to wrestle with the dealer- he only had one 2018 Denali and one 2018 SLT; neither of which struck my fancy, especially not for 50 grand+. Anyways- I called the dealer with the truck in question and I tried to chew'em down he said that's as low as he can go, so I asked if he could do title and registration for 31k out the door- he said OK. it's got everything except the sunroof.............

00pooterSS

iTrader: (40)

If you haven't bought it yet, there are crew cabs out there for 30k. If you have, congrats you'll dig it. But you'll wish you had gotten a crew cab at some point most likely.

Mark Johnson

iTrader: (1)

Thanks Pooter, I evaluated crew vs double and place a higher premium on the 6.5 bed(need to fit Prairie back there with gate closed and still fit in garage) than a larger cab, just me running around. And, with your advice about cleaning up the tune looking forward to a fun ride...………….

cheyenne383

iTrader: (25)

00pooterSS

iTrader: (40)

Mark Johnson

iTrader: (1)

Thanks Pooter, I settled on the 5.3. But after being totally honest with myself, and the way I drive the Denali(eggin' everybody on- getting mad at people because they don't accelerate fast enough) I concluded it best to go the 5.3, and the way it looks on paper- I re3ally am happy...…………….

00pooterSS

iTrader: (40)

I was sad about not getting the 6.2, but one thing that helped was realizing the LT 5.3 makes real close to the same power on e85 that the previous 6.2 did. With a couple of tweaks it makes the same or more.

Do a cold air intake and get the stock muffler by the flapper replaced with a straight through magnaflow and have the flapper cut out. I could tell a difference in power AND fuel mileage after getting the muffler and flapper done. Called Sam and said you're not gonna believe this but I picked up MPG (edit I originally typed power when I meant MPG) with the new straight through and flap delete, he said yes I will it's not the first time I've heard that.

When my truck was stock, 4 cyl mode and all, I got around 11 mpg on e85 and 14-15 on gas, being nice to it. Now if I baby it I get 16 on e85 and 19-20 on gas. And the 4 cyl mode is turned off. If I'm real hard on it I get 10-11 on e85 and that's all I run anymore. Sad I get the same (within 1 mpg) driving the **** out of it with no 4cyl mode as I did when it was stock and drove normal.

00pooterSS

iTrader: (40)

Ran some gas for the first time in a long time over the weekend, only run e85 usually. Right now it's about 25% e85 in the tank and 75% 93. If I ran 100% 87 or 93 and babied it it should do around 20 mpg mixed city and highway. Well over 20 on the highway. And again, that's tuned with the 4 cylinder mode deactivated.

Drove 200 miles and got 16 mpg not being nice to it at all. Several WOT pulls on the highway lots of time on back roads putting around neighborhoods looking at houses. Plenty of sitting at idle. Good mix of highway and city.

I edited the post above, I meant to type I picked up MPG with the muffler swap and flap delete. Looks like about 2 mpg. Headers are next, should pick up a little more MPG then too. And all along all of these moves increase power also. Nothing better than more power and more MPG

Mark Johnson

iTrader: (1)

Thank you thank you- I know enough good things can't be said for these gen 5 trucks and I'm so excited I'm about wetting the floor. I can't get Dad into Respite for another week and a half. Then I'm gonna get the truck, for now it's sitting there waiting...………..

00pooterSS

iTrader: (40)

Oh I figured you already had it. I'm sure the wait sucks horribly.

If you're curious about the flapper that needs to go, here's a vid that shows it really good.


Replace the big *** muffler with a straight through, leave the resonator it's already a straight through.

Get the flap cut out with the muffler swap