2017 GMC/Chevy DEF tank!

I remember when some website did a heavy duty pickup challenge within the last year or two the Cummins did use the most DEF. It isn't really a material cost overall, though - the stuff is pretty cheap.

Personally, I'd rather see my truck use whatever amount of DEF is needed to keep the exhaust within spec's than EGR. Those are the only two viable options when it comes to reducing nitrogen oxide emissions in Diesel exhaust; either reduce the combustion temperature in the cylinders with EGR or use a SCR after-treatment.

:):)

I'm not sure what I started but I seem to be quoted a lot on this thread...

Regarding the placement of the DEF tank. Agreed, it's not the best place, there is a lot of discussion even on GM forums about the possibility of it getting damaged, but if you read these threads, only a couple of people actually have damaged the DEF tank and usually the damage to the rest of the vehicle is greater than the DEF tank. So, when you have a perceived risk or issue, then the aftermarket companies come out with a solution even if it is not needed. Therefore you have companies like the one noted that say they developed the solution due to a reason. But if you read posts from people who actually use their trucks in the oil fields in AK or Canada, they have never had an issue. I read a couple posts where something went through the tank, but that can happen on a fuel tank just as easy, so not sure if that means anything. I think it would be really hard to damage the tank, maybe the outer casing, but not the tank unless you are really hard on your truck. If you are really into off road use, then you probably put larger tires on and a lift kit and now you really would have a hard time damaging it.

Regarding DEF usage. I do haul a lot with my truck. This past summer I hauled our horse trailer over 1000 miles then a couple weeks later took the 5th wheel to Yellowstone. According to GM you should get about 5000 miles out of the 5.3 gallon tank. I have had the low DEF warring light come on during 1 trip but was planning to go in for service soon after the trip so I just drove on. No issues. So, I just bring a couple jugs of DEF with me when I do an oil change and they top it off. I usually have some left over as it doesn't take the entire 5 gallons. I guess I am lucky that way? But, since we have 3 vehicles our truck is mainly used to haul a trailer or large loads. Both of our trailers are large and somewhat heavy. It looks like the new GM has a 7.5 gallon DEF tank which is why it might be a little easier to see especially if there are no running boards on the truck.

Now for all of you that are going to say - see he gets his oil changed at the dealer... It's free. The Chev dealer in my area offers free oil changes for life. That' a great perk on a Diesel.

I would've bursted that tank if it was on my Ram. I don't off road per-say, but the wife and I will drive down a few forest service roads near a couple CG's we go to. last year we drove over a rock that I didn't think was all that tall. I ended up putting a small dent on the underside of my running boards. If I had a DEF tank hanging their then it could've been dented or punctured. Or if I had a GM with that DEF tank hanging down I wouldn't be able to go down that road.

My 2011 f250 used maybe 2.5 gallons every 5k miles, this new truck needs a 30 gallon def tank! I know im going through twice what the old truck did, maybe due to the gearing, engine, tranny and driving are the same.

Huntindog wrote:

Me Again wrote:

Thermoguy wrote:




I've never had to fill mine up while on the road. I only fill it when I get an oil change. I agree it's not in a great place, but I like that it is hard to spill DEF on my paint.

You must not tow much! I add 2.5 box in the 1600 mile trip between Washington and Arizona.

The Rams seem to use a lot more DEF than the others. I tow a LOT, and on steep grades. My usage is consistently 3K per 2.5 gallons over 64K miles. Logged since new. I see no reason for a larger DEF tank.

My dad's '14 Ram uses much more DEF than my truck. We travel and camp together all the time. It seems he is constantly buying or adding DEF.

Huntindog wrote:

Me Again wrote:

Thermoguy wrote:
I've never had to fill mine up while on the road. I only fill it when I get an oil change. I agree it's not in a great place, but I like that it is hard to spill DEF on my paint.

You must not tow much! I add 2.5 box in the 1600 mile trip between Washington and Arizona.

The Rams seem to use a lot more DEF than the others. I tow a LOT, and on steep grades. My usage is consistently 3K per 2.5 gallons over 64K miles. Logged since new. I see no reason for a larger DEF tank.

Mine is pretty close to 2 percent usage compared to fuel consumption, but mine is rarely ever empty or unloaded. I would have to get 25 mpg diesel to get that low of DEF usage.

The_real_wild1 wrote:

Me Again wrote:

Thermoguy wrote:




I've never had to fill mine up while on the road. I only fill it when I get an oil change. I agree it's not in a great place, but I like that it is hard to spill DEF on my paint.

You must not tow much! I add 2.5 box in the 1600 mile trip between Washington and Arizona.

That sounds like you are going through too much IMO. My truck was filled when I bought it. I used 4 gallons in 9000kms. I added about 3 gallons at that point. Still haven't had to add any and I have put on 3500kms since then.

Is this towing usage? My truck uses a lot more towing than solo.

Thermoguy wrote:
I can't recall a single instance where I have read someone has had a problem with the location when off road or a farmer in a field.

You got to get from under that rock lol.

http://www.dieselworldmag.com/armor-protecting-gms-def-tank/

"As just one example, we spoke with a company that provides mechanical lube services to mining outfits in Northern Nevada, which reported more than a dozen tanks getting punctured or even scraped off on rough access roads."

It's not a common issue at all, but it does happen.