[cwalsh2]

I have a situation with my 2017 Colorado diesel. When I added DEF last time it did not hold the 2-2.5 Gal jugs I bought, so I had about an inch left and the tank was full right to the top. Today I decided to put in the last inch from the almost empty jug. The little cap just strips. I imagine the corrosive def dried and stuch the cap on tight! How to fix? nothing seems to work!

 

[Vinolush]

Try a little water around the cap to dissolve any exposed excess def... Obviously careful not to get any in the tank or fuel tank

 

[hand foot maneuver]

Ive gone thru two already, theyre cheap from the parts dept. one thing i found helpful was to break it loose with channel locks at the base. Havent needed another one since. They get all gummed up every time and the plastic is kinda soft. When its loosened i turn it back and forth a few times to break some of it out of the threads.

 

[JDB]

Yup. Channel locks kept under rear seat in that little visible tray. Just an arm’s reach away when standing at the darned DEF cap. Apparently a TSB and better cap avail now to better seal in the vapors.

 

[hand foot maneuver]

The new cap isnt much better. Channel locks still necessary

 

[SFLTruck]

Every time I get fuel I twist the DEF cap back and forth and let the crusty-ness out.

So far so good

 

[hand foot maneuver]

Thats prob a good move, im going to steal that move

 

[tmozeley]

The internal ratchet system broke on you. Remove the old cap, follow the TSB process , clean the threads well, and install a new cap. The TSB fix should create a better seal and eliminate the spills/crust.

Always keep the channel locks under the seat though!