DEF Freezing

[Trimble T]

We have a 2015 Ventana and i am wondering what others do regarding the fluid freezing during the winter months.

[ptw]

This is not a problem. From the Freightliner manual...

Freezing Conditions
DEF freezes to slush at around 12°F (-11°C). It is not damaged or destroyed if frozen, and is fully usable when thawed. The DEF in the tank is allowed to freeze while a vehicle is non-operational. At start-up, normal operation of the vehicle is not inhibited if the DEF is frozen; an immersion heater with engine cool- ant flowing through it warms the DEF once the en- gine is running, allowing the SCR system to operate.
Pre-2013 DEF supply lines are electrically-heated and are purged when the engine is shut down; com- plete purging of the DEF lines requires approximately five minutes after the engine is shut down.
DEF supply lines with engine model year 2013 and newer are designed to survive freezing conditions while containing DEF, so purging is not required.

[NealC]

Keep your gas tank AND def tank full when in storage.

[Algoma]

DEF actually lasts longer if it is cold, so don't be tempted to keep it warm.

[TJ]

Originally Posted by NealC

Keep your gas tank AND def tank full when in storage.

Really? I thought I read somewhere not to fill your DEF tank when storing a coach. Don’t remember where I saw it, though.

Neal: do you have any reference for that? I’m about to store my coach for the winter and the DEF level is just one green bar. I’d like to do the right thing, so if you have any detailed reference, I would appreciate it.

Thanks,

TJ

[NealC]

Camp Freightliner class.

[TJ]

Originally Posted by NealC

Camp Freightliner class.

Thanks, Neal; that’s good enough for me. I’ll pick up enough DEF to fill my tank.

TJ

[barnegatepic]

I know I just read in my buddys manual for his Chevy truck and it says not to fill the tank to full in the winter months. Kind of makes sense to me since it can freeze and burst the tank.

[Caliber]

Don't over fill, there should be a fill line marked on the tank. DEF does freeze, it needs space to expand when it does. If you fill it up to the cap and it freezes it will break the tank.

[ptw]

Originally Posted by Caliber

Don't over fill, there should be a fill line marked on the tank. DEF does freeze, it needs space to expand when it does. If you fill it up to the cap and it freezes it will break the tank.

I don't see a full line on my DEF tank. The tank fill spout is not at the top, but close to it, so it is not possible to completely fill the tank.

Looking at the Cummins website it says that DEF expands 7% when it freezes.

You make a good point!

[NealC]

Another thing I learned from Camp Freightliner is Diesel Kleen is now approved by Cummins. They make one (white bottle) for winter treatment and anti-freeze for the diesel. Click here for info on Amazon.