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DEF cap question

12K views 109 replies 21 participants last post by  CNS8888 
#1 ·
Hi, All,

I've been looking at the construction of the stock DEF cap on my pickup. It appears to be a four to five piece assembly with the two blue plastic parts snapping into one another, but having a little give between these two parts if you jiggle the thumb grip while the cap is installed. Is this construction to allow venting? Are these DEF caps supposed to be vented?

Eager to know.

-- Nicole
 
#2 ·
My stock cap was solid but the retaining piece with line was fixed around it. Either way, I replaced mine with a billet aluminum one week after I got it along with a billit fuel door replacement
 
#4 ·
Are these DEF caps supposed to be vented?

Eager to know.

-- Nicole
Due to the chemical composition of DEF, there's no reason for it to be vented. Venting, if anything, would allow the concentration of urea to change (additional moisture) and cause potential "Inadequate DEF" messages. The DEF tanks on any diesel truck should be as tightly sealed as any container DEF is shipped in.
 
#11 ·
Take your def cap off and suck on it, the cap is definitely vented. Curious mind wanted to know!!!
 
#19 ·
I've used one of the prototypes myself until I finished the production units. Now we've had a production unit on the filler neck for 5 or 6 weeks. I think it works great and is a pleasure to use. I've got to the point where I can talk on my mobile and remove and replace it with my left hand alone.

There's another thread:
http://www.cumminsforum.com/forum/2013-general-discussion/2265265-whats-deal.html

We've only had the website up and online for around 1-2 months, so it's a brand new product.

-- Nicole
 
#17 ·
I replaced my DEF Cap and my Diesel Tank Cap with Aluminum Billet Caps. The Def Tank had a plastic cap with a cord on it. The diesel tank had no cap ! I bought the Green Aluminum Cap to protect from dirt. I bought the Blue Aluminum DEF Cap so basically they both looked the same.I was going to put a larger tank on my Ram but I figure I can buy a lot of fuel with the $1450.00 I was quoted for just the tank and almost 8hrs. labor I was quoted at the shop I went to. (I think the scumbag sales person was trying to pad his own pockets). If and when I put a larger tank on my truck I will look for a locking cap. I have yet to be able to find one to fit it. They don't even sell them at the dealership.
 
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#18 ·
If you can add a locking def cap to your locking fuel cap that only leaves one thing to lock for the trifecta in your inventory. The under floor storage on the crew cabs. It would be cool to buy locking billet lids in a black coating. Those boxes have a liner that pulls out. Under the liner is where i stash valuables in the hopes that during a break in a thief will be unfamiliar with a Ram.
 
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#23 ·
CNS8888 awesome product. Buddy gave me one as a gift, works great. Definitely interested in the DEF version. Keep up the great work.
 
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#32 ·
Yes, the plan is to anodize aluminum components in bright finish blue for the DEF caps. That makes it so I can toss them in the laser and mark them quite easily. I do have a laser marking solution to paint/spray on unfinished aluminum, but I have never had good results with that method.
 
#36 ·
Progress report: We've been doing experimental machining. We've been making gains and finding setbacks on this locking DEF cap project.

Still on schedule, however!

Here's a photo showing the progress with components:



They're rough and they're unfinished, but we're still pushing forward toward R&D on experimental units.

:)
 
#38 ·
Great progress. Can't wait to see finished product. Also, I'm with nick00less on mirror option. That would be killer. Keep up the good work.


Sent from my iPad using Tapatalk
 
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#42 ·
CNS8888, I have a driver's side mirror that came in with broken glass, I can send you if that would help in the design?

2015 RAM 2500 Crew
 
#49 ·
To do those sort of parts, we need all the technical/dimensional specs. We love making all sorts of different stuff here, it's just that with our current production schedule we don't have a lot of time for searching specs. If a customer sends us specs, though, it would definitely be a lot easier to get the ball rolling! :)

I never say "no" to a consideration of a new project. My preference in this regard is to ask: what is it specifically that you want?

Looking forward to your reply. :)

-- Nicole
 
#52 ·
By the way, everyone,

Just minutes ago we concluded the initial testing of the locking mechanism on the first working prototype locking DEF cap. It worked perfectly.

We're now on to finishing the design of the top end and making one or a few working production-like units for further testing.

-- Nicole
 
#53 ·
Great, let us know when we will be able to purchase. Will they use same key as your cap? Thanks again.

2015 RAM 2500 Crew
 
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