I ordered a 2026 F250 and it will arrive in the next few weeks. I am under no obligation to buy it and so I am trying to decide if I should buy it or pass. If I knew DEF was going away in the next year or two I would probably wait until I could get one without DEF.

Does anyone know when DEF will go away or if it will go away at all? I hope it does but it wouldn't be the first time that a politician brags about something only to see that something never occur.

The FT4 emissions standards that diesel engines must meet are a part of the clean air act, which is a law. That is likely never going away. What Trump and the EPA overturned was the 2009 endangerment finding saying the EPA has no authority to madate emissions standards. Since the clean air act is a law enacted by congress and not the EPA, it is unaffected by this.

On a related note, manufacturers are not required to use DEF in their engines. They are only required to meet emissions standards. They just all use DEF since it is a somewhat easy technology to implement. If engine manufacturers really wanted, I'm sure they could find a way to meet requirements without DEF. There is just not much monetary incentive to do so.

As an example, in John Deere's newest combines with the new 13.6L engine, they were able to remove the DPF from the emissions system and still meet FT4 requirements due to changes in engine design over the old 13.5L engine.

Now what they could do is loosen the automotive standards by reclassifying the ozone thresholds which drive the vehicle tiers. Not sure if that is a target for them, but I know they have a lot on their plate right now so I'd be surprised.

On the idea to wait to buy a pickup, the big 3 are all introducing new larger diesel engines in 2027. We all know what happens the first couple years when a new diesel engine hits the market.

clarythedrill said:

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Of all the emissions requirements on diesels, the DEF is the least intrusive. I would much rather have the EGR and DPF get axed before DEF. Just my opinion.

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Nothing worse than a coked up EGR valve getting stuck coming down from the Cumberland Plateau putting you in limp home mode with a max speed of 25 mph.

Reorder the truck with a Godzilla. Problem solved.

cevans_40 said:

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I will never understand how burning liquid fertilizer helps make the air cleaner. But what do I know

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It's not burned... It's injected into the exhaust stream.
I'm guessing though that you knew that. Since diesels typically mix to run lean the DEF combines with NOx to recombine to NH4 & N2 which do not impact the Ozone.

Yes, it's a PITA, but I guess you could also eliminate DEF by rolling coal everywhere and running rich.

I don't dislike the DEF system. My 6.0 is totally gutted. It's loud, it's built, it will smoke if you get on it or pass someone and lay the pedal down. It stinks when idling and no breeze, etc. The modern diesels eliminate all of that and they putout equal or better power straight from the factory.

I think the DEF systems will only get better with time….and about the time they are reliable like the trucks, the EPA will move the goalposts and we'll have to start over. lol.

I just like seeing all the used DEF boxes everywhere at the gas stations. Seems like the dumbest things done for "clean air"
Would be great to buy one new without it.

if def doesnt go away, still, delete it

OP here. I take delivery of my new F250 this week. DEF compliant .

Now I'll start a thread about rims and tire options. Nothing says oil field service hand like a 50-something driving around in a tricked out Super Duty.