How far do you fill your FL Def tank?

[Stuart W]

I have filled mine to the red line in picture and still have 2 dashes on dash not reading, my Spartan had a line on the tank

 

[Rich W.]

I keep mine between 3/4 and full but I don’t fill it to overflowing. The tank is black, not opaque, so I can’t see the actual fill line. I wait until the dash “gauge” has been on 3/4 for a while (down one dash) then add on 2.5 gal jug. This keeps it between 3/4 and full without flooding the top of the tank.

I don’t recall the reasoning but some time back it was said that “over filling” could lead to DEF header problems. I don’t know if that’s true, but its easy enough to manage it this way. That also might have been a Spartan specific thing.

I would agree that your tank level reading is incorrect, but I don’t know that its a problem. If it wasn’t still under warranty, I would just manage it as stated above to prevent it reading any lower. Since it is, it would probably be best to let FL check it out.

 

[Neal]

Like a car until the pump cuts off.

 

[Stuart W]

Like a car until the pump cuts off.

I’m actually using 2.5 gallon jugs so the only clicking I’m hearing is my back from holding the jugs
The reason I ask, on my Spartan I one time overfilled the tank and had a Jeep covered in Def. This happened from filling on the drivers side at a truck stop.

 

[Neal]

It sounds like your prior coach had a leak somewhere. It should be a sealed system hypothetically. I would fill the new coach to the top with cap secure and see how it goes. I never had an issue and I always top off at the tank. Was never a concern.

 

[Stuart W]

It sounds like your prior coach had a leak somewhere. It should be a sealed system hypothetically. I would fill the new coach to the top with cap secure and see how it goes. I never had an issue and I always top off at the tank. Was never a concern.

I had checked into it at the time and found that Spartin actually had a fill line on the tank and the way the drivers side fill port was situated if you let it click off it would be higher than the fill line. Spartan had designed a vent in to the top of the sending unit plate that would vent fluid when overfilled this is what sparked my question in this thread. Sounds like the FL design is different.

 

[Neal]

I recall your setup had an option to DEF fill from either side of the coach. Does your 23 DSDP have this?

 

[ARD]

Spartin actually had a fill line on the tank

I loved it when there was a fill line. It was so easy. Now the DEF tank is black so can't see a thing. My standard MO is when I'm at ½ tank, I add 5 gallons and call it good.

 

[DennisT]

Yeah, can’t see anything in the black def tank on the Superstar either.

On the trip to Ohio from Florida I went to 3/4 twice and just put the nozzle in and stopped when it clicked off. Gauge said full so I’m good with that process.

 

[rvkev]

Thankfully I do NOT have one of those Diesel Exhaust Fluid tanks. Only have a one fuel tank and a propane tank.

 

[Rich W.]

I wait until Im down about 1/4 (one green dot) and add a 2.5 gal jug, much like the method employed by @ARD. Keeps everything in the tank wet and at over 300 mpg of DEF I can do it at my leisure.

 

[DKRITTER]

I too usually fill with jugs from Tractor Supply. My DEF tank is on the passenger side and it's a PIA to fill it at a truck stop.

A while back I was looking for an easy way to fill w/o using a funnel I had to clean all the time and discovered if you'll wait until you need 2 jugs (2.5g ea) you can use the supplied hose from one as a funnel while you fill with the other.

 

[MemoriesByTheMile]

When parked for a period of time, we like to keep DEF full but NOT 100% filled if there will be freezing temps as we understand DEF can expand a bit if it freezes.
When leaving after parked for a long period of time, we like DEF to get as low as possible (assuming we are driving long enough to make this happen) so we can then refill with fresh DEF. Will fill until the pump goes off (truck stop pump fill, our DEF is immediately next to our fuel tank).
Coach age predates the rash of DEF header issues in past few years so we just want to keep DEF tank float sensor wet and avoid DEF aging too much.

 

[JRS]

Stuart, I've been filling from the drivers side via Truck Stops, wait till the pump stops and have yet to have any issues doing it this way.

 

[Stuart W]

I recall your setup had an option to DEF fill from either side of the coach. Does your 23 DSDP have this?

Yes both sides

 

[Stuart W]

Stuart, I've been filling from the drivers side via Truck Stops, wait till the pump stops and have yet to have any issues doing it this way.

Thank you , I believe that was a Spartan issue only

 

[Rustymayes]

I filled mine at the tank cap today until the nozzle shut off. A few hours after returning home I noticed a puddle had formed under the tank so I assume there is a vent that burped out some DEF as the day warmed up. I will be keeping it down a few inches in the future.

 

[Stuart W]

I filled mine at the tank cap today until the nozzle shut off. A few hours after returning home I noticed a puddle had formed under the tank so I assume there is a vent that burped out some DEF as the day warmed up. I will be keeping it down a few inches in the future.

What chassis do you have?

 

[Rustycoach]

What chassis do you have?

Freightliner

 

[redbaron]

I keep mine 1 bar above empty when storing. When driving, I will fill based on distance with goal of parking with very low levels.

This has worked well for me since 2012 on 2 freightliner and 1 spartan.

The key to Def is to keep it fresh.