Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
RV Trip Planning Discussions

Go Back   iRV2 Forums > TRAVEL TRAILER, 5th WHEEL & TRUCK CAMPER FORUMS > Trailer Towing and Tow Vehicles Discussion
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 10-18-2017, 04:02 PM   #1
Junior Member
 
Join Date: Sep 2015
Posts: 8
Smile Def fluid use questions

iNew diesel truck and I am not familiar with this def fluid use. So, my question is , should I keep my def tank on the full side always? I had a guy say that filling it back up when it is down to half full is the worst thing I could do. I am confused! Anyone with suggestions about where to find good info so I can get educated ? Thanks for any help guys ! Sorry for the long story!:
highrider is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 10-18-2017, 04:07 PM   #2
Senior Member
 
BuzzWolfAR's Avatar
 
Forest River Owners Club
RV Trip Wizard
Join Date: Aug 2016
Location: Mountain Home, Arkansas
Posts: 832
My F350 has a 5 gallon DEF tank. The indicator says full until 2.5 gallons (One box) is used. No other messages until 500 miles left.

I add DEF when I get the first signal, when it will take 2.5 gallons. I DON'T want to get low.

If you use a dealer for oil changes, they should keep it full for you. Ask.
__________________
Buzz & Jo Wolf, Mountain Home, Arkansas
TV 2014 Ford F350 Lariat Diesel
Fiver 2018 Cedar Creek 29ir
BuzzWolfAR is offline   Reply With Quote
Old 10-18-2017, 04:49 PM   #3
Senior Member
 
tuffr2's Avatar
 
Join Date: Sep 2012
Location: Palm Coast Florida
Posts: 12,995
I always let my Ford diesel get to 1/2 all the time. The worse thing you can do is spill DEF on the paint and not clean it off.

Like the previous poster. I check it manually on the instrument cluster. I also have a 5 gallon DEF tank. The containers are 2.5 gallon. When I have 1/2 showing I put a full container of 2.5 gallons in.
tuffr2 is offline   Reply With Quote
Old 10-18-2017, 05:11 PM   #4
Senior Member
 
Old-Biscuit's Avatar
 
Join Date: Nov 2015
Posts: 26,642
Quote:
Originally Posted by highrider View Post
iNew diesel truck and I am not familiar with this def fluid use. So, my question is , should I keep my def tank on the full side always? I had a guy say that filling it back up when it is down to half full is the worst thing I could do. I am confused! Anyone with suggestions about where to find good info so I can get educated ? Thanks for any help guys ! Sorry for the long story!:

Look up 'owners manual' for whatever model of truck you have and read what MFG. states about DEF---then follow their recommendation


Did you question 'guy' as to WHY it was worst thing to do.......and what was his reply/reason?

Whenever someone makes a bold statement I always ask followup questions cause MAYBE they know something ----MAYBE they are just full of it.
Follow up answer usually breaks the tie
__________________
I took my Medication today. HAVE YOU?
Dodge 3500 w/Tractor Motor
US NAVY---USS Decatur DDG-31
Old-Biscuit is online now   Reply With Quote
Old 10-18-2017, 05:25 PM   #5
Senior Member
 
xrated's Avatar
 
Join Date: Jan 2017
Location: "Murvul", TN
Posts: 1,653
Quote:
Originally Posted by highrider View Post
iNew diesel truck and I am not familiar with this def fluid use. So, my question is , should I keep my def tank on the full side always? I had a guy say that filling it back up when it is down to half full is the worst thing I could do. I am confused! Anyone with suggestions about where to find good info so I can get educated ? Thanks for any help guys ! Sorry for the long story!:
Sorry to be the bearer of bad news, but your "guy" probably needs to stick with subject matter that he maybe knows something about, because he obviously doesn't know anything about DEF systems. The DEF tank is just a res. for DEF fluid that is sprayed into the exhaust system to help break down the NOx emissions being emitted from the diesel fuel burn and turn it into harmless nitrogen and water. It would be kind of like saying that when your fresh water tank gets down to the half full level, filling it back up is the worst thing you could do. No Sir, the worst thing I could do is listen to your bad advice.

Here is a fairly quick read on DEF systems and why and how they work....
http://www.trucktrend.com/how-to/exp...asic-training/
__________________
2016 F350 Crew Cab Dually Diesel King Ranch 4x4
2018 Grand Design Momentum 394M Toy Hauler
Excessive Payload Capacity is a Wonderful Thing!
xrated is offline   Reply With Quote
Old 10-18-2017, 07:15 PM   #6
Senior Member
 
Join Date: Apr 2014
Location: On the Road
Posts: 1,608
When mine says less than half full (checked on instrument cluster) I drive it a few days and add. Otherwise it will not hold it. My service advisor said to never let it get down to 500 miles to empty or starts counting down as it screws up the computer and you'll end up at the dealership. Talk to service manager at your brand of dealership.
__________________
2012 Nu Wa 363RSBDA
2016 Ford F-350 Dually 6.7
Duoglide1 is offline   Reply With Quote
Old 10-18-2017, 08:38 PM   #7
Senior Member
 
jacknife's Avatar
 
Join Date: Sep 2013
Posts: 1,500
DEF is time sensitive product. If you are running around not towing it lasts a long time. When towing you use much more. I never fill it full unless l am towing . It will also freeze which is a good reason not to fill it to the top . It is all made to the same standards. I have Bought Wall Mart def , Peak and out of pump in a Truckstop. Never a problem with it. Napa usually sells 2.5 for about 10.
jacknife is offline   Reply With Quote
Old 10-18-2017, 10:56 PM   #8
Senior Member
 
Dropthejacks's Avatar
 
Join Date: Jan 2017
Location: Liberty, NC
Posts: 829
I'm with everyone else. I run it down to about half empty and dump another 2 1/2 gal jug in. Brings it right back to full. The RAM barely uses any at all when just riding, but it'll move the needle when you hook up and start pulling.
__________________
2016 Keystone Outback 328RL
2019 Chevy 3500HD DRW
1 Slobbering English Bulldog for ballast
Dropthejacks is offline   Reply With Quote
Old 10-19-2017, 05:56 AM   #9
Senior Member
 
Join Date: Nov 2016
Posts: 233
I think what your friend was thinking, is DEF has a shelf life. You always want to newest/freshest jug. It is not good to buy some and store it, as it can go bad. Most say don't buy anything more than six months old. As long as you are driving your truck, and not park it for a year, you should not have to worry about the DEF going bad as you are always adding fresh stuff which is mixing with the "old" stuff.

Buy it anywhere you want, it is all made to the same standard. Although I would stay away from a no name one. Your truck will not know the difference between the $10 Wally World 2.5 gallon version or the $20+ 1 gallon version at your dealer. The freshest is off the pumps at a truck stop, although not the easiest with a Chevy as in their wisdom, they placed the filler as far away from the pump as possible.

Mark
Wileykid is offline   Reply With Quote
Old 10-19-2017, 06:36 AM   #10
Senior Member
 
petrel's Avatar
 
Join Date: Sep 2015
Location: Urbanna, VA
Posts: 1,154
Glad this came up. For the guys with new Fords. Are there any prohibitions on using truck stop, or brand X DEF in your trucks?

I also saw it mentioned that the stuff can freeze, how do you manage this if the truck is parked in freezing weather?
__________________
2006 Renegade Classic 3200DM/Freightliner Coronado Chassis/Series 60 Detroit Diesel 515hp.
https://www.irv2.com/photopost/showga...er=170823&sl=p
petrel is offline   Reply With Quote
Old 10-19-2017, 10:44 AM   #11
Junior Member
 
Join Date: Sep 2015
Posts: 8
Thumbs up Thank you!!!!!!!!!!

I just wanted to say thank you to all of you guys that responded to my question about DEF. The link to more info was great. Glad I found this forum with helpful people here unlike the last forum I visited with the same question. I was feeling really dumb.
highrider is offline   Reply With Quote
Old 10-19-2017, 12:07 PM   #12
Junior Member
 
Brwk's Avatar
 
Join Date: Sep 2017
Location: Maryland
Posts: 16
And don't let anyone try to scare you into buying the most expensive stuff. They all have to adhere to the same standards. Just remember the fresher the better and most have date codes on the package. Pretty much a year shelf life.
Brwk is offline   Reply With Quote
Old 10-19-2017, 12:30 PM   #13
Senior Member
 
Join Date: Apr 2014
Location: On the Road
Posts: 1,608
The trucks DEF tank has a built in heater. Even if frozen in the am it takes care of itself. The only cautions I know of is to not stock up with several jugs and don't carry them around in the heat of the summer. I do make sure it's ISO approved and not old stock. I don't care who's name is on it.
__________________
2012 Nu Wa 363RSBDA
2016 Ford F-350 Dually 6.7
Duoglide1 is offline   Reply With Quote
Old 10-19-2017, 12:44 PM   #14
Senior Member
 
Cypressloser's Avatar
 
Join Date: Sep 2013
Location: Alberta - East of the Rockies, West of the Rest
Posts: 831
Freezing is, as previously mentioned a non issue.
When buying make sure the jugs still have the original seal to make sure they contain DEF and not water.
__________________
2018 Ram 5500 with 2021 Arctic Fox 1140
Cypressloser is offline   Reply With Quote
Reply

Tags
fluid



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
DEF consumption or MPG of DEF? erstanfo Class A Motorhome Discussions 16 03-13-2016 02:00 PM
DEF Or No DEF TeresaOwen1 iRV2.com General Discussion 46 12-07-2014 07:00 AM
How much DEF fluid does your coach use? WIDGET33 Class A Motorhome Discussions 31 11-17-2013 08:01 AM
Allison Transmission Fluid? OK What fluid to USE? k1hog Workhorse and Chevrolet Chassis Motorhome Forum 11 02-07-2008 08:54 AM

» Featured Campgrounds

Reviews provided by


All times are GMT -6. The time now is 09:18 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.