Monday, November 28, 2016

Trustworthiness Versus Credibility in Auto Repair


A lot is said about trust in the context of auto repair.  While trust is important, I think it’s often confused with credibility.  Consider this common scenario:
A motorist drives into a shop for a diagnosis of his check engine lamp.  The car runs fine.  After an hour of testing, the service advisor tells the car’s owner that the problem is actually inside the engine, in the timing chains and gears, and it’s going to cost $5,500 to repair.  The car is still running ok for now, he says, but if the problem is not repaired the car will not pass state inspection, and will eventually suffer greater damage.




The service advisor says he knows that’s a lot of money, and a big surprise.  But he’s seen that same issue before and it’s actually happening to a lot of cars like his as they get over 100,000 miles.  This, by the way, is a real example on Mercedes V6 cars.

Hearing that, what does the customer do next?  It’s a much bigger expense then he expected.  The customer might say he wants to seek a second opinion, or he might just schedule the repair.   What he does will not have much to do with trust.  It has everything to do with credibility.

From a client’s perspective, a trustworthy mechanic is one who does not lie to them.  A credible mechanic is one they can count on to give them the correct answer.   For a business to enjoy maximum success it must be both trustworthy and credible.

Investigative television shows have traditionally been fond of filming “stings” where they try to catch dishonest service personnel recommending parts cars don’t actually need.  While that can be a result of dishonesty it is more often a result of incompetence or even different service standards.

For example, when a car comes in with a complaint of unstable steering, an incompetent advisor may recommend new shocks.  In fact, the car has worn out control arms and he didn’t see that.  He’s not dishonest; he simply wrong in his diagnosis.

In my experience technical competence is the biggest problem facing our industry at all levels.  That speaks to the importance of credibility.  What makes a repair shop credible?

Long term clients decide a shop is credible based on long experience, where the advice they are given proves correct over the long haul.  Clients who are referred start with a presumption of credibility because their friends say things like, “I’ve gone there 10 years and they are the best.”

How does someone who does not have a personal referral choose a credible shop?  Most people today turn to the Internet.  Imagine a new client is standing in the waiting room of Shop A, and he just heard the news in my example.  What would assure him the shop is credible?

He’s driving a Mercedes, and the service advisor just said his problem is showing up in other cars like his.  Looking in the parking lot, he sees 10 other Mercedes cars like his own.  That speaks to credibility.  What about the Internet?  If the service advisor said something like, “If you Google E350 timing chain problems, you can read all about the issue on your car.”  Would that increase credibility?  Probably some.

What if the service advisor said, “We fix those timing chain issues fairly often, and we’ve gotten pretty good at it.  Would you like to see some photos of a job we just did, so you can understand what we do and why it costs what it does?”  In my opinion, that would increase credibility a lot to a stranger.

What if the service advisor said, “Are you a member of the Mercedes Club?  I’m a technical advisor and long time member, and we just hosted a tech session where we talked about this very thing.”  That too would increase credibility.

In the examples above I hope I’ve shown that credibility is actually a bigger deal that trustworthiness.  As indeed it should be.  Straight-out liars are not too common.  Insufficiently skilled and incompetent auto service personnel unfortunately are.


What else would make a repair shop credible to a new potential client?


John Elder Robison

(c) 2016 John Elder Robison
John Elder Robison is the general manager of J E Robison Service Company, celebrating 30 years of independent BMW/MINI, Mercedes, Land Rover, Rolls-Royce and Bentley restoration and repair in Springfield, Massachusetts.  John is a longtime technical consultant to the car clubs, and he’s owned and restored many fine British and German motorcars.  Find him online at www.robisonservice.com or in the real world at 413-785-1665

Reading this article will make you smarter, especially when it comes to car stuff.  So it's good for you.  But don't take that too far - printing and eating it will probably make you sick.

Wednesday, November 23, 2016

What do worn brakes look like?

I am often asked what worn brakes look like, when looking through the slots in the wheel. Can you tell from outside, or does the car need ot be put on a lift and have its wheels removed. Here is a rule of thumb. Look at my finger pointing to a brake pad in the photo below.

 

In that photo you see the shiny brake disc, the frame of the caliper, and the outer pad.  The pad consists of a metal plate with friction material laminated to the backing.  The rule is: the thickness of the friction material must be greater than the thickness of the backing plate.

The reason for that is heat insulation.  If the pads wear down to nothing there is no longer any insulation and the heat of braking will transfer from the rotor, to the backing plate and from there into the pistons and fluid.  If the fluid gets too hot it boils and you lose your brakes.


This photo shows the same pad and caliper seen from behind.  The thing in the center is the wear sensor, which as you see is in contact with the rotor.  That put the brake wear light on in this car.  IN some European cars the light has to be reset with a test tool even after the sensor has been changed.

Other cars - like BMW - also calculate how many miles the pads have run and they will light the warning based on mileage even if the pads are good (for example, if someone replaced them without a reset)


John Elder Robison

(c) 2016 John Elder Robison
John Elder Robison is the general manager of J E Robison Service Company, celebrating 30 years of independent BMW/MINI, Mercedes, Land Rover, Rolls-Royce and Bentley restoration and repair in Springfield, Massachusetts.  John is a longtime technical consultant to the car clubs, and he’s owned and restored many fine British and German motorcars.  Find him online at www.robisonservice.com or in the real world at 413-785-1665

Reading this article will make you smarter, especially when it comes to car stuff.  So it's good for you.  But don't take that too far - printing and eating it will probably make you sick.

Tuesday, November 8, 2016

The Value of Oil Filtration

Everyone knows that oil filters are supposed to trap particles that might otherwise damage the engine.  



In a modern engine the passages that carry oil to the bearings are typically between one-tenth and one-quarter inch in diameter, which means that a good sized chunk of debris or sludge may block them.  The clearances between rotating parts like the crankshaft and the bearings is generally no more than a few thousandths of an inch.  That is tight enough that a grain of sand can get jammed in there and do considerable damage.

The filter is a modern engine’s protection against that. Nowadays the oil filter is immediately downstream of the oil pump, so the filtering happens before the oil reaches any bearing surfaces. All the oil that passes through the pump should pass through the filter, which is why today’s systems are said to have “full flow filtration.”

Most of the time the particles trapped by the filter are invisible but in this example the benefit of the filter is obvious.  The car in question is a 2008 Mini Cooper S.  Like many of its brothers this Mini had a problem with the timing chain and guides.  In this particular car the plastic guides were broken by the chain, and they landed in pieces in the sump.  The car was repaired with a new chain kit, but some pieces of plastic remained hidden in the sump.

Five thousand miles later this was the result. The bits of plastic that were left behind pushed through the oil pump inlet screen and passed through the pump gears.  Then they flowed into the filter, where they were trapped and held.



The filter looks scary, but the simple fact is, it did its job.  If this car had not had a filter - or if it had a cheap aftermarket filter that ripped – this engine would be toast today.  As it is, a new filter and fresh oil sent the car on its way.





Oil filters need to have filter paper or felt that is fine enough to catch the smallest abrasive particles yet strong enough to resist penetration by larger sharp-edged objects.  I hope you can see from this example that a good oil filter is all that stands between you and a $10,000 engine replacement.  Given the minimal cost of a OEM-grade filter, this is not an area where it pays to cut corners.




John Elder Robison

(c) 2016 John Elder Robison
John Elder Robison is the general manager of J E Robison Service Company, celebrating 30 years of independent BMW/MINI, Mercedes, Land Rover, Rolls-Royce and Bentley restoration and repair in Springfield, Massachusetts.  John is a longtime technical consultant to the car clubs, and he’s owned and restored many fine British and German motorcars.  Find him online at www.robisonservice.com or in the real world at 413-785-1665

Reading this article will make you smarter, especially when it comes to car stuff.  So it's good for you.  But don't take that too far - printing and eating it will probably make you sick.