[Wressell95]

I recently purchased a used f30 320i, 2019 b48 engine, 45k miles, full-service history.

After a couple of weeks, I got a notification saying the coolant was low so bought some HOAT coolant to top it up with, as that is the spec for the car.

After putting 2/3rd Liter into the main coolant reservoir I noticed the colour didn't quite look right to me that was inside, I took a syringe and pulled out what was in. The previous owner has put OAT coolant into my car!


So, two things, is this going to be a really big issue right now, and should it be flushed immediately, or can I wait until my service which is booked in for around a months time and ask them to flush it then?

Thanks!

[Billfitz]

Either OAT or HOAT will work, but they shouldn't be mixed. I doubt that 2/3 liter would be catastrophic, but if it was me I'd do a flush and refill with HOAT. I wouldn't pay a dealer to do it, though.

[F32Fleet]

Originally Posted by Wressell95

I recently purchased a used f30 320i, 2019 b48 engine, 45k miles, full-service history.

After a couple of weeks, I got a notification saying the coolant was low so bought some HOAT coolant to top it up with, as that is the spec for the car.

After putting 2/3rd Liter into the main coolant reservoir I noticed the colour didn't quite look right to me that was inside, I took a syringe and pulled out what was in. The previous owner has put OAT coolant into my car!


So, two things, is this going to be a really big issue right now, and should it be flushed immediately, or can I wait until my service which is booked in for around a months time and ask them to flush it then?

Thanks!

It's fine. You can mix blue G48 with green HT12.