I finally spoke up when a guy at the parts counter said all DEF is the same

I was picking up a filter in Boise last week and overheard a guy telling a new tech that all Diesel Exhaust Fluid is the same, just buy the cheapest jug. I had to step in. I ran a fleet of ten school buses for three years, and we had constant sensor issues when we used a bargain brand from a truck stop chain. Switched to a major brand that meets the ISO 22241 spec exactly, and those problems just stopped. The cheap stuff can have impurities or be off-spec for urea concentration, and that can mess with the SCR system over time. It's not worth saving five bucks a jug to risk a four thousand dollar catalyst. Has anyone else seen a real difference in DEF quality, or am I just being too careful?

3 comments

3 Comments

paul_owens257d ago

That "four thousand dollar catalyst" thing is a scare tactic. I've run the cheap stuff for years in my work trucks and never had a single warning light. Those sensors go bad on their own all the time, you just got unlucky.

the_emery5d ago

My buddy's F-250 needed a whole new fuel system last year. Cheap additive clogged the filter and took out the injectors. Cost him way more than the good stuff ever would.

jade7386d ago

Oh man, I totally get where you're coming from. I mean, maybe @paul_owens25 has had good luck, but I've seen the cheap stuff leave a chalky residue in the tank that messed with the pump. It's one of those things where it might work fine until it suddenly doesn't, and then you're stuck with a big repair bill. I stick with the branded stuff that shows the ISO spec right on the jug. It's just not a part of the truck I feel like gambling on.