DEF usage towing
This is a discussion on DEF usage towing within the RAM 1500 Diesel Towing & Hauling forums, part of the RAM 1500 EcoDiesel Forum category; I just completed a 3500 mile road trip from Texas up through NM, CO, UT, WY, SD, and back. I towed a 21'Toy hauler (4000lb) ...
Post By DavidG
RAM Jr Member
DEF usage towing
I just completed a 3500 mile road trip from Texas up through NM, CO, UT, WY, SD, and back. I towed a 21'Toy hauler (4000lb) and avg about 15mpg. When I left home my DEF tank was 3/4 full. In CO I had to load 5 gallon of DEF. 2000 miles later in eastern CO I noticed I was almost empty again. I had to stop in Dumas TX and fill up with another 5 gal of DEF. Is this normal to use that much DEF while towing? Normal driving I may use 1/2 tank in 4000 miles.
2015 Ram 1500 Lone Star Ecodiesel
2017 HD Ultra Limited Low
RAM Sr Member
I can't say if that's normal or not, but the amount of DEF your truck uses is directly related to the amount of fuel you burn. I don't know what the ratio is, but burning more fuel while towing means you'll use more DEF to treat the increased exhaust gases.
Your amount of usage is about right. Went on a 4300 mile trip to Yellowstone/Glaicer/Teddy Roosevelt NP and burned thru bout 3/4 tank of DEF. Towed a loaded 6000# TT.
2015 Ram Laraime EcoDiesel
Purchased 9/2018 W/ 14500 miles
RAM Diamond Member
Try to figure how many gallons of fuel you normally burn per gallon od DEF. Just guessing you use about a gallon of DEF per every 40 gallons of fuel. Surprised you can get 15 mpg towing that toy hauler as mine, with GDE, does say 14. Anyhow that would be about 600 miles per DEF gallon.
Now you could get ZERO DEF usage. I have only used a 2 1/2 gallon container of DEF in near the last 90,000 miles. Used that for the AEM change so I could drive it home. After that 25 mile ride I put water back in the tank. GDE.
If you wrestle with a pig you'll both get dirty and the pig loves it. .