[asado111]

Is a coolant flush necessary?

[ndog14]

Originally Posted by asado111

Is a coolant flush necessary?

Eventually, yes.

As vague as that sounds, the circumstances around your question are vague.

[E90Company]

Yes

[CubanJJ09]

Maybe

[mike3000fl]

i change coolant every couple years but I have not flushed in the traditional sense.

my water pump is original at 149,000 miles.

[Healey3000]

Originally Posted by asado111

Is a coolant flush necessary?

Hi,

BMW plays a strange game on this one. The official line from HQ appears to be that it is a lifetime fill yet they say it is condition based. The dealers therefore get to make their own recommendations and HQ will support the dealer's position.

This is very strange but I think it lets BMW get out of putting coolant changes on the list of free maintenance items. On my car, when I took it in for its final maintenance, they told me I should replace the coolant but BMW won't cover it.

I am personally not a fan of lifetime fills of anything in a modern car. Granted, fluids have improved a lot but they are still subject to degradation. It's very interesting to note that these lifetime fills started showing up after BMW offered the free maintenance; coincidence??

Coolant contains anti-corrosive agents that protect the head and block. Over time, these get depleted and then you are at risk for head gasket failure or head/block damage. I was "trained" on my E34 with the M30 engine as on that car, a coolant change every two years was critically important. The only approved coolant was the OEM one, with good reason.

In a nutshell, I would recommend that you flush the coolant to maximize engine and pump life. Others may have a different opinion.

Regards.

[Tom K.]

BMW went to a "Lifetime" (100,000 miles?) coolant around 2006 or so. Prior to that, it was to be changed every 4 years.

Tom

[5tony]

Originally Posted by Tom K.

BMW went to a "Lifetime" (100,000 miles?) coolant around 2006 or so. Prior to that, it was to be changed every 4 years.

Tom

The funny thing is that it's the exact same coolant they used ten years ago!

[Healey3000]

Originally Posted by Tom K.

BMW went to a "Lifetime" (100,000 miles?) coolant around 2006 or so. Prior to that, it was to be changed every 4 years.

Tom

I called BMW NA to discuss this issue and they tap-danced around in fine fashion. I could almost feel the customer service "manager" squirm as I pressed him.

Regardless of what they choose to call it, BMW is talking out of both sides of their mouth on this topic. For what is costs to have the coolant flushed (or DIY, preferably), the payoff could be substantial.

Preventive maintenance - I'd easily convince myself to stretch out a gearbox oil change, but not coolant.

Regards.

[jphughan]

BMW says lifetime fill these days but that's relatively recent and wasn't accompanied by a change in the fluid.

Mike Miller's Old School BMW Maintenance Schedule says to flush every 2 years.

[TheTal0n]

I think its a good idea...Just cant seem to find any coolant suitable except buying from the dealer/online.

[Clifton]

To add a data point to the conversation, 2003 E46's have 4 year intervals for flushing coolant. On 2004 E46 cars, BMW dropped the coolant flush from their maintenance program and called the coolant "lifetime". BMW, however, did not change or update the coolant.

Flush your coolant.

[F32Fleet]

OEM is just G48 and years ago I was told to flush when changing brands of coolant whereas drain and refill if using same. Flushing takes a lot of distilled water.

[Tom K.]

Originally Posted by Clifton

To add a data point to the conversation, 2003 E46's have 4 year intervals for flushing coolant. On 2004 E46 cars, BMW dropped the coolant flush from their maintenance program and called the coolant "lifetime". BMW, however, did not change or update the coolant.

Flush your coolant.

I wasn't sure of the exact year when stating "2006 or so", but I recall that my '03 Z4 still called for the 4 year flush. By 2007, my dealer initially wasn't going to cover the service but after checking, they did with no problem.

Now, due to the "new and improved coolant" I don't have to worry for the rest of my life (or is it my car's life?).

Tom

[Clifton]

Originally Posted by Tom K.

Now, due to the "new and improved coolant" I don't have to worry for the rest of my life (or is it my car's life?).

Tom

Oh it is *special* alright, Tom. All it takes to make the coolant new and improved is a new container and an updated label. To make it last a lifetime, they didn't even need to change the ethylene glycol formula to do it, so it must be magic.

New vs. old gallon of BMW coolant:


The current (left) vs. previous label of the same BMW coolant. Note the subtle addition of "Long-Term" and the exclusion of "change coolant every 3 years":