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New 2018 GMC Sierra Z71 Impressions

draperfish

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draperfish Enthusiast

draperfish

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     I just got a new 2018 GMC Sierra SLT Z71 and thought I'd share my thoughts so far. My previous trucks have been: 1996 Silverado regular cab 5.0 2WD, 1999 GMC Sierra extended cab 5.3 2WD, 2003 GMC Sierra extended cab 5.3 2WD, 2006 Tundra double cab 4X4 with 4.8 , 2007 Tundra double cab 4X4 with 5.7, 2009 Tundra double cab 4X4 TRD 5.7, 2014 RAM CrewCab Sport 4X4 5.7. I had gotten away from GM because the power of the Toyota and RAM 5.7's was so much better than the 5.3 , I test drove a 2014 GMC Sierra with the 5.3 and it was horrible, just felt like it had no power at all, the Hemi felt like a sports car in comparison.

      I was looking at the incentives on the 2018's and the deals just seemed too good to pass up (15K off msrp) so I figured I'd give the GMC's another look and try out a 6.2. I bought the Sierra at the beginning of October with 4 miles on the odometer, right now I'm right at 4,000 miles. I've been very impressed with the 6.2, I can definitely feel the power difference over the hemi, the acceleration is awesome and so fun to drive. It pulls hard all the way up to the speed limit without ever revving over 3,000 rpm, several times I've punched it hard and wound it out but can't stay there long before it's doing 80 mph!

     The ride is stiffer than the RAM, but I'm not surprised since the RAM was a sport model and the GMC has the Z71 package. I had just bought new tires for the RAM, so I made the dealer switch them out, the Sierra had 275/55r20 SRA's, the new tires are BFG All Terrain KO2's 275/60r20's, the clearance is tight in the front with the wheels turned full left or right but so far I haven't seen any rubbing. A few times I've noticed a clunky downshift, but it's only been when I've pressed the gas hard to accelerate and then immediately let off (when I punch it and then someone pulls out in front of me), otherwise the transmission shifting has been very smooth.

     I check the oil about every other tank of gas and at 4,000 miles it hasn't changed. I also check the gas mileage every fill up, actual mpg is usually 1 or 2 mpg less than what the computer is showing, my best mileage has been 20.4 on a 300 mile trip, in town I'm averaging around 16 mpg which I've very happy with, my Tundra 5.7's averaged around 13 mpg and the Ram 5.7 was around 14 or 15. I've only run 93 octane gas, with one tank of 91 octane (thanks Oklahoma! lol).

       I thought there was something wrong with my front end, but it turned out to be the lane departure assist, wasn't expecting the steering wheel to pull like that all of the sudden! lol The front collision alert is a cool feature but has scared the crap out of me a couple of time when it's gone off with the flashing lights and loud beeping.  My Ram had touch and go keyless entry and automatic windshield wipers, I do miss those features especially the wipers and wish GM had included them on a loaded SLT Premium Plus package. So far I'm loving this truck. 

Grjfer Enthusiast

Grjfer

Posted
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All that and not one picture of the truck. Joking, nice assessment I just moved from a 15 SLT 5.3 to an 18 SLT 6.2. That 6.2 is a beast. 

draperfish Enthusiast

draperfish

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1 hour ago, Grjfer said:

All that and not one picture of the truck. Joking, nice assessment I just moved from a 15 SLT 5.3 to an 18 SLT 6.2. That 6.2 is a beast. 

 

 

 

IMG_9771.jpg

Grjfer Enthusiast

Grjfer

Posted
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Tires look great, fill out the wheels wells pretty nice. 

 

Here's mine. 

 

IMG_20181118_144223.jpg

GPGuy Senior Enthusiast

GPGuy

Posted
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1 hour ago, draperfish said:

Very nice, black and white are my favorite truck colors. 

Black, white or blue are definitely my top choices for color on my next truck. 

14 gmcl83 Enthusiast

14 gmcl83

Posted
Posted

I just ordered new tires for mine truck .stock is 275/55/20 now I’m going to 275/60/20 BFg k02 my truck does have a 2 inch level kit too.E6F9F8DA-A558-4D95-9DEC-E74D59B5E474.thumb.jpeg.147c6a19c6e5dd6b2c26861fd5098af4.jpeg

Grjfer Enthusiast

Grjfer

Posted
Posted
1 hour ago, 14 gmcl83 said:

I just ordered new tires for mine truck .stock is 275/55/20 now I’m going to 275/60/20 BFg k02 my truck does have a 2 inch level kit too.E6F9F8DA-A558-4D95-9DEC-E74D59B5E474.thumb.jpeg.147c6a19c6e5dd6b2c26861fd5098af4.jpeg Wow that thing is defying gravity. 

 

300 Blackout Enthusiast

300 Blackout

Posted
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Congrats on the truck! I enjoyed reading your write up. I’m glad to hear you didn’t give up your KO2s. Lots of great offerings out there related to truck choice and you’re fortunate to have been able to own so many. I recently drove a friend’s F150 and was really surprised at how nice of a ride it was compared to my 2014 Sierra (my 10 ply tires aren’t doing me any favors) but there are trade offs that I like better on the Sierra.

It sounds like you don’t mind getting into the throttle when needed. The L86 (and L83) are great engines and if you choose to keep the truck “forever” or that you wanted to start modifying it (add a blower, turbo, etc...) you have an excellent starting platform with the L86. It can handle another couple hundred horses with only modifying the parts actually creating the power and a tune. Your driveline, specifically your driveshaft, will be the first thing holding you back. I’m very impressed by what both the L83 and L86 are capable of achieving. A member on here added twin turbos and an upgraded fuel pump/injectors to his L86 crew cab with a tune of course. With no other mods he’s running 10s in the 1/4 mile. Pretty crazy for a full sized truck.

I never had auto wipers but I sure do miss keyless entry and push button start. Meh, no biggie.

Yondu Enthusiast

Yondu

Posted
Posted

Congrats on the new truck.  I will say E load tires won't help your ride, neither will the Z71 package.  Could always swap out shocks... I just did at 789 miles. Need an alignment before I can drive it enough to give my thought on them though.  

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