VIN is required to properly access parts, unless we’re talking about pre-1980 cars.
If the repair shop is not doing that then they are sadly behind the times and probably lacking in quality, tooling, experience, and resources in other aspects as well. Entering a vehicle (with VIN) into the customer database takes seconds and all I need to do is look out the window and see the license plate.
I have to ask the obvious question here, that magnetic ride control was an expensive option when the vehicle was new. Why would you think the replacement parts would be cheap?
They don’t come from Monroe, that’s why they are not available from Monroe/Tenneco. Monroe has NO clue how to make these dampers or even how to control them with an ECU.
If I mistakenly bought a vehicle with such a shock and found they needed to be replaced I would be looking for a way to retro fit hydraulic shocks. I don’t sip hot lattes while driving across logging trails so they aren’t worth the price.
Just curious, anybody know how those magnetic shocks work? Is it just two permanent magnets opposing each other? If so, seems like they must be pretty strong magnets. I’d keep the old parts and salvage the magnets for any magnetic experiment I might decide to try.
It’s almost certain to be a linear motor in the shocks @GeorgeSanJose and I imagine they have some powerful magnets. I have wondered what metalurgists did to make magnets so strong.
It’s a simple system, in essence. The fluid in the strut (damper mechanism) is impregnated with metal particles that stay in suspension, and then an electric charge is introduced to the magnets in the strut creating an electromagnetic system. Varying the electricity introduced to the system makes the magnets stronger or weaker, in effect making it easier or harder for the fluid to travel through the strut. It’s a variable viscosity damper. Or something like that.
GM also used a system like this in their power steering systems. It was called MagnaSteer.
Actually they were Cadillac ‘Magnaride’ shocks. The customer should have been asked if they would accept the standard Buick shocks which were originally offered at the much lower price.
Caddy had the stabilitrak system which worked with the variable stiffness shocks. U can install low end “Chevy” shocks in place but ur fancy ride control don’t work now. They had resistors that plugged into shock wiring to make computer happy.
Part of what you paid for is getting the MRC parts quickly. If the local parts store keeps them in stock, they have storage fees associated with keeping them on the shelf as well as overhead costs. Brakes Plus also has overhead fees on top of the marginal cost to install the MRC shocks. If you could have waited for the repair, you might have found a shop that would order them from GMDirect or let you drop ship them since there is only one supplier. This isn’t normal practice since the shop wants to control the source of ther parts, but that is not an issue here. I’m sure this was an option and the base trim shocks could have been installed instead. Brakes Plus might not have understood this since their mechanics are likely to be inexperienced. That is standard at low cost chain stores.
Brakes Plus would never be my trusted shop for service. I’ve heard stories of their upselling. Also, heard that you go in for pads and come out with all new parts that were not needed.
Yes I can tell you how they work. I was an engineer assigned to the product for many years. The shock hydraulic fluid has little iron particles in it, coated so they float in oil. In the presence of a magnetic field, the fluid tries to become a solid, or generally gets much thicker. The magnetic field is generated by a very small coil (acutually 2 coils these days) inside the shock piston. Turn it up and the shock gets stiffer, turn it off and it gets softer and anywhere in between. The electrical signal come from an electronic brain that’s fed information from 4 suspension position sensors, a 3 axis accelerometer, a yaw sensor, the steering sensor, plus some engine and brake data. All that is used to make a decision as to how firm each shock should be every 500 microseconds based on several hundred parameters adjusted by the engineer that “tunes” the whole thing. There can be a selector switch that allows some additional adjustment range. The system helps ride, handling and assists the stability control to control the car when things go bad.
Thanks for everybody who commented on my car repair experience. I didn’t
start this conversation trying to get any kind of revenge on the shop. I
was trying to see if I had been told the truth along the way. I had two
questions. Was the part I could have bought on-line the same quality as
the part I had installed. When the shop told me that they had charged no
mark-up was that a lie.
Here’s what I learned. They probably bought the strut for $470 or less &
charged me $875. It was the same original GM part. Nobody in this
conversation thought the part would be some copy. It came off the same
assembly line with the same manufacturer warranty.
I will know in the future to avoid this shop & tell anybody who asked to do
the same.
Also to the people who compare the mark-up on these struts as similar to
buying a bottle of aspirin for $5 but paying $8 at a hospital a good
comparison , I say “bull”. You pay so much for hospital care because of
the non-paying patients. If you go to a hospital they fix your broken leg
whether you can pay or have insurance. If I go to a shop with a broken
strut I better have some money.
I have an audit done on a large local non profit hospital @larrylitle55 and being non profit is a book keeping technical term. In a town of <35,000 the hospital showed an annual profit of $49million and bragged how profitable Medicaid was for them.
Thanks MGM for the explanation. I’m not seeing the above part. I can envision the magnetic field orienting the metal particles from random to all in one direction, but don’t see why that would make the fluid more or less viscous. And don’t see why all the metal particles don’t sink to the bottom of the shock. I haven’t yet read the link tho, hopefully will be explained there.