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2015 Sierra All Terrain 6.2/8 speed is here!

JumpMaster82d

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JumpMaster82d Enthusiast

JumpMaster82d

Posted
Posted

First, I'm coming from a 2014 Sierra All a Terrain with the 5.3 and 3.08 gears and got this truck as GMC lowered the towing rating on the 2014 by 2k lbs. This thread isn't about that issue but rather the review of the 6.2/8 speed.

 

I'm a gear head by heart and have worked on cars for the better part of 20 years which in turn makes me a picky person of sorts when it comes to how a vehicle performs.

 

Bear in mind, my 2015 only has 72 miles currently and I picked it up with 3 on the clock. The 8 speed is nice. With that said its not without having faults. I noticed it had a pretty harsh 1-2 shift when the trans was cold (and it was 38 ambient). There is MUCH LESS gear hunting compared to the 6 speed. And when it does decide it needs another gear, it's able to do so at a much lower RPM which is virtually un noticeable. The only way you can really notice that it's doing anything is to watch the tach and observe how quick this thing goes through the gears.

 

One thing I did notice between my 2014/2015 (both All Terrains) is the 2015 has the "off road" screen with the angles the truck is acending or decending.

 

I'll update this thread as I get more miles under my belt and have a better idea how things are performing. Overall I'm very impressed between the two trucks.

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Roidz Enthusiast

Roidz

Posted
Posted

Gorgeous! I ordered mine in the same color.

 

 

Sent from my iPhone 6+

roadblock Enthusiast

roadblock

Posted
Posted

This is the EXACT truck I am hoping for. I'm in the same situation, lowered tow rating on my 5.3L 3.08

Jumpmaster PM me if you have time about the process you took to do this. GM Canada has told me they will get me a new truck, but I haven't sorted out the details with them.

Bmotoman Enthusiast

Bmotoman

Posted
Posted

Very Nice!

 

My double cab version of the same truck was built and shipped this week.

 

This makes it much harder to wait. Stupid slow trains.

Anglerman Enthusiast

Anglerman

Posted
Posted

Jumpmaster, glad to see you got your new ride. Very nice! That's the exact same truck I was going to order before I decided to spend a few more bucks and the get the Denali. I like the grill and the color accented wheels that you got with the All Terrain package. I agree with your statement the only way you can really tell what the 8 speed is doing shift wise is to watch the tach, the shifts are that smooth both up and down. Let me know how your does on gas mileage after you have a chance to drive it some more, I hope to put some miles on my this weekend.

Stex Senior Enthusiast

Stex

Posted
Posted

Nice, enjoy. Good to see some on the road. Question, is the 8sp quick to downshift when given more gas? Thus not a lag on down shift as with the 6sp.

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