[Öperator]

So I've gotten the "Incorrect DEF fluid 200 miles..." message. I got the warning about a week and a half ago, and it cleared on it's own?!? Didn't add anything. But it was gone for over a week. Now it's popped back up. I plan on requesting the NOX warranty service and a drain. But that brings me to the title of the thread.

What are recommended DEF's. Currently I have a mix of:

BlueDEF PLATINUM
https://www.walmart.com/ip/BlueDEF-P...ctedSellerId=0



States: "Tested to meet or exceed the strictest OEM standards
Conforms to the ISO-22241-1 specification for DEF, and is an American Petroleum Institute (API) certified diesel exhaust fluid"

and

Shell Rotella® DEF
https://rotella.shell.com/en_us/prod...dHRlci9lbl91cw



It states: "high purity diesel exhaust fluid meeting the stringent requirements of ISO 22241 and is API registered as a certified DEF."

Both seem like quality options, so I don't get why I'm seeing the message twice. I've only had the car about a month, and initially had to fill it up because I got the low DEF warning. I can't be the only one not using BMW branded DEF. And if BMW branded DEF is the go too, where is the most economical place to purchase outside of the dealer. I have seen some recommend VW DEF, I had a Sportswagen TDI and didn't even know that was a thing.

[ssf556]

Can you elaborate on the Warranty DEF drain?

I am a 20 year veteran of the diesel industry and I feel like DEF is DEF. Really I think it comes down to storage. I keep a couple of boxes in a closet in my office to minimize temperature/humidity changes that happen in my garage. I also keep my DEF tank topped up with fluid, I just feel like something that is full works better than something that is empty, minimizes small particles that settle at the bottom of the tank getting pulled through the system.

[Öperator]

Originally Posted by ssf556

Can you elaborate on the Warranty DEF drain?

I am a 20 year veteran of the diesel industry and I feel like DEF is DEF. Really I think it comes down to storage. I keep a couple of boxes in a closet in my office to minimize temperature changes that happens in my garage. I also keep my DEF tank topped up with fluid, I just feel like something that is full works better than something that is empty, minimizes small particles that settle at the bottom of the tank getting pulled through the system.

The warranty is just for the NOx sensors. The drain would be of the "incorrect" fluid. But replies I'm seeing are the DEF fluids I'm using are legit, so I may skip the drain.

[capt_slow]

All you need to do is ensure the fluid conforms to the ISO-22241 specification for DEF. This is implied in the owners manual as AUS 32 itself meets ISO 22241.

Alternatively recommended: NOx Diesel exhaust fluid AUS 32.

There should be a compliance statement printed on the box of the DEF. Personally, I use the standard Peak stuff not the premium version. They can be found at Costco Business Centers for $13/box.

[dakoo12]

I live in Canada and have a 2015 X3 28d with about 175k on it. Originally had the DEF fluid is low warning and to refill. However after a few days of driving without doing anything the warning changed to "incorrect fluid 200km ish left before no start". Took the vehicle to the dealer as I knew there is extended warranty on the NOx sensors and my gut was telling me that was the issue. Sure enough the SA told me the codes and issue were due to the NOx sensors and not the def fluid. The NOx sensors have already been replaced a couple times on my truck too. Still under extended warranty luckily. The warranty in Canada is 10 years or 193k. So everything for me at this point should be covered, but hell these sensors are the worst. Might go for a delete once I'm past warranty. DEF fluid should be good to go as long as it ISO 22241as mentioned before.