Magnetic Ride Control Struts, High Cost to Replace



I’m sorry, but those 2 statements you made seem to contradict each other


The particles are suspended in the liquid by the magnetic force. When the liquid has to move, the particles must move as well. This takes more energy, and the liquid appears to be more viscous. In reality, the liquid is the same as it ever was. An analog might be turning oil to grease. Particles can be mixed with the oil to thicken it. The magnetic suspension goes a step beyond this by using an oil that will not normally suspend the particles, but will support them when the magnetic energy is added.


Each iron particle is coated with a material with less specific gravity than oil, or floats in oil. The oil is just a PAO synthetic base oil much like any really good shock oil. The iron has a higher specific gravity and sinks in oil. With the right amount of coating, the particle become neutrally buoyant so it doesn’t settle at the bottom nor does it float at the top. This has nothing to do with any magnetic field inside the shock.

In the presence of the magnetic field, the particles try to link themselves so the shear stress increases. The actual viscosity doesn’t increase but the shear stress between the iron particles does increase. It acts like a Bingham plastic which few beyond physicists really understand so its easier to say the viscosity increases.

The piston has an annular passage the oil flows through when the shock moves. The coil is in the middle embedded in an iron core. The piston sleeve that rides in the bore is magnetic steel and the annular gap between the two at each end is the magnetic field path where the particles “get grabby” when they pass through.

The concept has been around for decades. The keys to making it work in a shock is to use materials the iron won’t wear away in an hour and to make them buoyant. The chemistry to make the shear stress go as high as possible is also a biggie.

Then we get to the electronic drivers circuits and the control theory. And THAT is a whole 'nother complicated bag 'o worms…


OP, you do not seem to understand how things should and must work at an automotive repair shop.

Since you think that I’m full of “bull” I will add this to your comment about hospital and getting a broken leg fixed free of charge. The hospital MAY be fixing that broken leg free of charge to the person who has the broken leg but someone else (a lot of someones…) IS paying for it.

A cut and paste comment from the state about my area for instance which does not include taxpayer support…
In order to offset the cost of indigent care, Tulsa’s hospitals use foundation support or shift non-reimbursed costs of indigent care to insured patients. It is reported that Tulsa hospitals use at least $9 million in private funds for indigent care.

So should the cost of your replacement broken strut be passed on to other customers?
By the same token, should the cost of someone else’s broken strut be passed on to YOU?

Just my 2 cents, but if you go to a shop with a broken strut then yes I agree with you, you BETTER have some money.


I apologize for my “Bull” comment.
It was a poor choice of words. I don’t agree with your prospective but I
was out of line with that comment. For that matter I apologize to anyone
else who might have been offended by anything I said.
Everybody has the right to their opinion, & everyone has their prospective
& life experiences that shade that prospective.
I learned a lot from these comments & appreciate everyone taking the time
to throw out their opinions & thoughts.


I apologize if I came across as a bit crass. It’s just that over the years as a mechanic I’ve had to listen to so much grief about the cost of repairs that it (usually) upsets me a bit.

I do agree completely that some repairs are horribly expensive. I remember back in the 80s when Subaru was having a rash of automatic transmission failures due to internal seal leakage. A new Subaru at the time was 10-14k dollars depending upon year. The replacement transmission was 5 grand; and that’s just for the transmission alone. That did not include gaskets. fluids, labor, and tax; with the latter being about 500 bucks here in OK. And these failures were through no fault whatsoever of the car owners.

Some owners (low miles, just out of warranty, and as new) were very and justifiably upset over the cost of a trans replacement being roughly half the cost of car new.
I went to bat for the owners with Subaru of America and no amount of pleading on their behalf would catch them a break. SOA would simply not budge an inch.
The shop and the mechanic were the ones catching the brunt of the customer’s ire; at least until they calmed down and saw where the bulk of the cost came from.

As for the Magnetic Ride Control; one should ALWAYS assume that something high tech or even gimmicky has a high repair cost involved.
Much like Lincoln Mark VIII HID headlight bulbs. On eBay; 2-300 bucks, used.

All of this new car technology (automatic braking, on-board displays, etc) all has a high price and some point a lot of people are going to get sticker shock when it has to be fixed.
Wonderful when it’s working; not so much when it ain’t. :frowning:


+1 in a posted reply because I can’t “thumbs up” this reply enough.

I cannot understand how people can buy a premium car and then expect that parts for it should cost the same as a Mirage or a Versa.

A $50,000 car with tires that cost $500 each? Yes, those huge low profile run-flats are expensive. A brake job costs $1900??? Those 6 piston Brembos with the extra large performance rotors can’t use the $10 AnyBrand brake pads and $40 Chinese rotors.


I’m not offended in the least but I do have a question for you. The shop needs to make a profit on work they do. Would you feel any better if they charged you exactly what they paid for the parts but increased the labor charge to maintain the same level of profitability? All shops do this. By shops I include ANY company that buys parts to repair things. They need a certain amount of money above and beyond their costs to remain viable as a business. You’re certainly free to shop around if you feel they are gouging you. You’ll probably find that any shop worthwhile will have about the same “out the door” cost to you regardless of how they divy up the charges.

Of course, this does not include the exception they failed to follow through on.


OK, I understand better now. The little particles are just tiny magnets, floating neutrally buoyant, & in a magnet field they line up n-s n-s n-s forming in long chains. I can see how that could indeed affect the beefed-up fluid’s resistance to shear forces and therefore the apparent viscosity. Thanks again for the explanation.


Everyone in every business is going to mark their parts or goods up. A plumber is certainly not going to provide that 3/4" PVC elbow at his cost only nor is an electrician going to provide 50’ of Nomex without a markup.

I remember back in the early 80s a boss of mine at a dealer where I worked took a Lincoln in trade. He sent it back to service to get the headlights operating again; a procedure which he figured would be no big deal. Wrong.
The car had the (at the time) high tech headlight switch called a Twilight Sentinel I believe and the switch had failed.
The Lincoln dealer wanted 800 bucks and change for a new switch and that was after a 10% dealer to dealer discount; and keep in mind that was 35 years ago.

Every decade is going to have their share of high priced widgets.


One of the things you are seeing here is a business philosophy that is commonly used with new technology. In business school, it is referred to as the Polaroid model. You’re a start up as Polaroid was and you need capital to expand. You make a small number of your product and sell it at a very high price. If your product is desirable, you make a huge profit that you can use to increase your factory size, make more of the product, but at a lower price (law of supply and demand).

This continues until your factory is large enough that you can make the product and sell it a price the masses can afford and you still make a profit.

In the automotive industry, new technology usually appears on a low production model, often in the high price range. That way, the more well off among us pay for the development of the technology and eventually it makes its way down to the less affluent masses.

There are some exceptions, the new Camry engine for the 2018 model has new technology that was tried on the FRS/BRZ platform. Low production but not a real high cost vehicle like a Lexus would have been. You have to be careful of which small group of customers you potentially might piss off if it doesn’t work.


This has been around for quite some time. I recall when they came out as standard equipment on the Corvette back in 2003. Here’s some good info on the technology-

What I did not know is that it appears a foreign company now owns it. But it has been around long enough that it is filtering down to more mainstream platforms…


Owned by the Chinese, Engineered by what’s left of the engineering center in Kettering Ohio. Built in Mexico.


Hi Mr Mustangman, i have a question for you… i have the magnetic ride control on my Buick lucerne 2007 cxs
and i want to change it active to passive strut/shock… but i need to know what is the maximum electrical pulse on the strut so i can put a resistance on it… BTW sorry for my English i’m french thank you


The coil resistance is less than 1 ohm… right about 0.8 ohms. Add a resister across each strut or shock wire connection and that should be enough to “fool” the system into thinking shocks are still there an avoid the “Service Ride Control” message.


Thanks a lot!! Couldn’t find this information anywhere on internet… Live long and prosper my friend ; )


The resistor is big though. Pinky size. Not grain of rice size


That is a strange value, as with 14 volts applied,that is a current of 17 amps. x4 that is 70 amps, a very high value. Perhaps only a volt or so is applied to the coil, perhaps a low duty cycle pulse train?


Correct, peak-hold pulse-width-modulated drivers. The speed of the system depends on creating a magnetic field as quickly as possible but once established, the current can be reduced. And the coil never sees battery voltage.

Similar can be said for collapsing the field to return to the soft damping. Tricky circuits and software to suck the current back out of the coil.


Magnetic Ride Control Struts?

Part of the research I do before purchasing a vehicle (or other mechanical / electronic device) is to determine whether or not I’m purchasing something with shockingly expensive repairs waiting in the wings. That is one advantage to purchasing “used” vehicles with a historical track-record available for viewing.

Magnetic Ride Control Struts describes something that would never be found on one of my vehicles. Many cars go down the road comfortably, safely, and generally just fine without them.

So, I guess if one is into that type of thing then they have elected to pay the price or if not then better research prior to purchase should be done.

From what I recall there is a basic law of thermodynamics that covers that situation, eh?

CSA :palm_tree: :sunglasses::palm_tree: