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BMW X3 coolant alarm highlights how owners' manuals torture service advisors

How a simple thing like a low coolant level can pit customers against the dealer service advisors.

While driving in a 2013 BMW X3 recently, the coolant level alarm appeared on our screen. It advised that the driver should immediately refill the coolant level. Assuming the worst, we watched the temperature gauge and were able to get the vehicle home. Luckily we were only a couple miles away. Now what?

Where is the Coolant?
Once home we did more investigating. We consulted the manual on how to check the coolant level. Unlike every single modern car I have ever seen (besides BMWs) the coolant is not stored in a visible “overflow reservoir.” Instead, it is inside what looks like half a bowling ball. The car being still hot the coolant inside could be a vapor of coolant and steam, so we waited a couple hours for the vehicle to cool and then looked inside. There was no fluid at all inside. Not low, empty.

Consult Your Owner's Manual - At Your Own Risk
Consulting the owner’s manual advised that if coolant is below the low mark to “slowly fill coolant to the specified level and do not overfill.” The owners’ manual for the BMW X3 advises to only add “suitable additives.” BMW in the owner’s manual also then advises the owner to “Have the cause of the coolant loss eliminated as soon as possible.” We waited a day for BMW to open and phoned our service advisor.

BMW Service
Calling BMW’s service department made things confusing. The service advisor we have come to trust (since this car has had multiple issues requiring major repairs) told us to “Just add tap water and drive on over for a quick pressure test.” That sounded to me a lot like what one might do with an old clunker, but who would think to add to add tap water, with all its calcium, manganese, iron and other metals, minerals, and compounds that can precipitate and later clog a thermostat or cooling channel? It also made us wonder what might happen if we added the water, then drove onto the highway to bring the X3 to the dealer and then the coolant all leaked out again? We would risk being stranded or possibly overheating the engine while we drove to a safe location to await help.

Add Tap Water To Radiator?
We actually called the dealership twice because we could not believe the advice to add tap water to this near $50K vehicle. The reason we hesitated to do that was that the car’s manual specifically says to only top-off with “suitable additives” and which went further and even says “not all commercially available additives are suitable.” Another reason we don't like the idea of adding straight water is that if we add too much water the coolant may lose its freeze resistance and cause us trouble later. On the second call, the advisor said, “We see this all the time.” Discussing the tap water issue, he said, “That is what we do.” When pressed he did admit that the dealership would use something other than tap water.

Service Advisors Are On the Front Line
We cannot fault the BMW service advisor. If he does indeed “see this all the time” then BMW is doing its customers a major disservice by saying one thing in the owner’s manual and then having its authorized dealers say something different. Doing so sets up mistrust between the customer and the BMW dealership. Should the owner trust the BMW dealership or the car’s owner’s manual? We found ourselves getting frustrated with the service advisor, who was only doing his best to help.

The rest of the saga is not germane to the point of the story. We wondered, what would our car-savvy readers do if they had a breakdown, and the dealership’s advice did not seem to match the owner’s manual. Comment’s below are welcome.

UPDATE - After publication the vehicle was filled with 16 ounces of water to between the min and max level. It was driven to the BMW dealership in Peabody, Mass. There, BMW's dealer staff added a few ounces more of BMW coolant and sent the owner on her way. No pressure check or other mechanical inspection was performed. By all appearances the BMW X3 can consume about 20 ounces of coolant in 5 months of operation. It was last serviced in February.

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Trevor Willmot (not verified)    July 21, 2014 - 9:39PM

One would hope that the service advisor was trying to save you the cost of a tow or pick up service being aware you were not hundreds of kilometres away. Also one would hope and believe that in investigating the problem, even if they already had a fair idea because of previous similar experiences with this model,
that the remedial process would involve a system flush, and refilling with the correct coolant mix etc.
In this instance topping up with water to get to a close point of repair is extremely unlikely to cause any problem. However it should not be done as a routine process because it dilutes the correct mix ratios of whatever is used for coolant. Personally I usually carry a small reserve of the correct mix ( 2l) either on a long trip or have it handy in the shed at home when only travelling locally.
I hope BMW gave you a list of generally available additives you could use. Without that their advice is almost worse than useless. BTW I have had BMW bikes for years but would be unlikely ever to have a car. Actually, in many ways I think they have lost the plot in both directions, in many ways I would sooner have my older 50/60's bikes back.....

John Goreham    July 21, 2014 - 9:53PM

In reply to by Trevor Willmot (not verified)

Thanks Trevor. No, the manual page (hard to see) does not tell me what type of coolant to buy locally (as in Walmart, Autozone, whatever) and the dealership suggested tap water. Not DI water, not distilled. Hard to believe. Towing is free with either AAA or the BMW Roadside Assistance. In my youth when I drove older cars, due to necessity, I did exactly what you do. I will post an update if I can. Your comment is much appreciated.

Josh (not verified)    July 21, 2014 - 10:08PM

I would say the tap water is sufficient to get your car to the service facility, BMW will replenish whatever coolant is lost during the repair with new coolant (not reused) as for the minerals in standard tap water, replacing your coolant every 3-4 yrs will prevent corrosion even if tap is used rather than distilled. Anybody who believes that bmw's rating of lifetime coolant is a fool. BMW just uses a lifetime service interval on their vehicles to bolster their low maintenance cost claims. 14k oil changes, lifetime transmission fluid, Haha! Try getting 200k reliable miles from that car, not happening!

Trevor Willmot (not verified)    July 22, 2014 - 12:06AM

Hmm , the irony of it all is, is that it is more important than ever to have the correct fluids to hand, be it oil or coolant, these days, as everything is that much more critical, especially the European cars! Look at VW's extended oil changes, can't mix more than 500ml of an ordinary oil in an emergency only, with some of their special oils etc. You really do have to carry your own as you won't find it in out of the way places. ( Here in NZ anyway.) Anyway I'm sure it will be O.K. As a former warranty person I never quite decided who were the more annoying, those who didn't bother to read their manuals,, or those who did, and sometimes the manuals have misinformation, outdated information or like yours only sufficient to cause worry but offer no real assistance.
Of course if you had distilled water it would have been better, but I'm betting your service guy knows that most people don't have distilled water lying around, even for their batteries. If you had to go out to get it you might as well buy the right stuff, except you can't because the idiot manual doesn't give you a list of acceptable products! If you have free towing then I would have used BMW's service as it is their product and their problem, if I was really worried about it.
Sounds like the tech figured the water would get you there but it wasn't worth putting the expensive stuff in for the short trip because it was likely to end up allover the road again. As a motorcyclist I appreciate that, don't need anymore slippery toxic stuff on the road thank you/

Raj B. (not verified)    July 18, 2018 - 10:23AM

I have a X3 as well and was surprised how stupid the min/max labels are. The bottle is black (no problem with that) but you need to look down the coolant resovior to see the level. On the older BMW's, there was a float that would come up when you opened the cap. Being in hot coolant ment that the float would break and fall inside.

I keep BMW coolant at home because you can't purchase it locally. There is a company called OEM that makes coolant for these cars however, I rather buy genuine.

With that said, a top up with tap water would not hurt your engine. If there system has 6.5 litres and you add 1 litre of water, you would reduce the boil over and freezing protection but improve heat transfer. Unless you see -20 C or drive in heat heat, I doubt you would have any issues. In fact, I've run my cars with nothing but water and addivities.