2017 GMC/Chevy DEF tank!

I'm not sure how you defend that design. Running boards do not fix it.

The ground clearance is 8+", the rear differential or front suspension lower arm would hit an obstruction before the DEF tank.

As I understand it, the tank bottom is even with the bottom of the frame rails. What sticks down is the cover.

I don't recall ever reading about one being drug off or damaged in the previous models when it was installed in the same place. It may be more of a perceived problem than an actual one.

I, for one, wouldn't be doing that kind of offroading in a $50-70K truck anyway. That's what used beaters are for. :)

My Ram chassis cab has a 9+ gallon DEF tank that does not sit as low as GM's. I don't think it would take GM much engineering to redesign the tank with a thinner longer profile so it tucks up closer to the rocker panel.

In stock form, GM trucks do sit lower than a comparable Ford or Ram, so having something hanging that low on a 4wd is inviting damage. I've seen enough deep potholes on logging roads where that tank could be compromised even if you are traveling slowly. The longer the wheelbase, the more this becomes an issue due to the reduced breakover angle.

You all got me curious, so I just checked my 2014. The DEF tank does hang down, but my running boards hide it (mostly). But looking under the truck, the rear Deferential definitely hangs lower than the DEF tank. So, after thinking about this for a few minutes, I came up with a solution. This is not my photo, but ... here's a solution. DEF tank will have no problems hitting anything if you do this "simple" modification:

Looks like a great opportunity for the aftermarket!

If a company is willing to let something distracting as this works its way into a production model, who knows what other engineering compromises they made behind the sheet metal that we can't see. It really doesn't matter whether it's a legitimate ground clearance issue or not. If a certain percentage of consumers perceive it as a "flaw", or just plain ugly, at a minimum they're going to lose some sales over it. It's hard to believe the engineering team at GM couldn't have done a better job of hiding that DEF tank. It's just a big ole wart on an otherwise fine looking truck.

Is there a step molded in to it?

I agree they should've raised/modified the DEF tank for the 2017s. That said, for 99 of users it'l be high enough. Where it could be a pita is for ranchers.

Overall though, given the "underpowered" old models dominance, these 2017 GM Duramaxes are going to spank the Powerstroke and Cummins in the tow tests, fwiw.

But yes, I'll stick with my Cummins as it's paid for and I don't care how fast I can get up a hill beyond a certain point....even though Dodge's electrical gremlins make AAA a must.

Perrysburg Dodgeboy wrote:
. . . you have to admit this is not one of GM's proudest designs! Kinda like the gas tanks on the 1970's C/K trucks.

x2. One of my first jobs was delivering auto parts in a 1972 C10. I used to wonder what all that sloshing noise was inside the cab. About 2 months into the job I was looking for something I dropped behind the seat. Took a peek and couldn't help but notice that gas tank. Even as a naive teenager, back before auto safety was a big deal, my first thought was WTF?!