Item #: GG-EZDEF1
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The DEF-Loc is the locking/tamper-resistant DEF cap for Dodge Ram diesels. Locking up your DEF prevents unwanted matter from being put into your DEF tank. The DEF-Loc also features an EPDM U-Cup seal and also has a venting feature cut into the underside of the stainless steel Secure Screw head.

Each DEF-Loc comes with the DEF-Loc cap and one machined stainless steel Secure Key. The locking DEF cap is not designed to work with the OEM tether.

Will also work on Cab & Chassis model trucks.



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May 31, 2018  |  By Paul John Kisselbach
FINALLY, after 4 years, I found a quality locking DEF cap and locking fuel cap for my 2014 Ram, thank you!! What a relief it is!!

Well thought out
Jan 7, 2018  |  By Patrick Orlando
I little weird to figure out at first, but works great, just have to turn lock like a screw, a simpler half turn type would be nice.

Works Great Looks Great
Jan 4, 2018  |  By Tyler
As soon as I saw they now had a locking DEF cap I jumped on buying one for my truck to go along with the locking Diesel cap. It looks great and works great.

Love the blue
Dec 15, 2017  |  By Chelsea
Since locking the diesel up, was concerned about someone tampering with the DEF. I got a DEF-Loc a couple of months ago. It works nice and smooth. Love it.

Nov 13, 2017  |  By Stephen
This locking def cap works great on my 4500 it does look different at first because of its size but no problems at all

Peace of mind (2)
Nov 9, 2017  |  By Justo R.
Bought the fuel cap so makes sense to get this also. Careful NOT to over tighten, just snug it up.

Well worth it
Nov 2, 2017  |  By R Anderson
Great product. Added security to keep undesirables from messing with your def system. A little work required to install and remove but heh your not filling the tank very often. Well made and definitely well worth it.

Great Locking Cap For Your Diesel!
Oct 27, 2017  |  By Michael
I recently purchased the fuel fill locking cap for my 2027 Ram CTD and was very pleased with the quality and ease of use . When I saw Geno's Garage offered the same style locking cap for the DEF tank, I immediately ordered the product. This is another high quality product with the added benefit of only needing one key to open both caps. These are great products that will protect your vehicle's fuel & DEF supplies. Geno's Garage never fails to impress me with their great products, fast shipping and World Class customer service.

Work great
Oct 17, 2017  |  By Terry W Scheehle
I love this cap. Finally feel safe not having a locking fuel door.

Sep 17, 2017  |  By Dave K.
Purchased this item along with the EZ Lok diesel fuel cap, works as advertised, looks great, definitely recommend!

Install and Tech Information