Why I became a DIY mechanic

We’ve had our Mercedes GL320 for nearly eight years now, and it has accumulated about 130,000 miles to date. For the most part it has been a good choice for us but as it ages I am faced with a harsh decision.  That decision is whether to continue paying Mercedes repair shops exorbitant amounts of money to keep the GL320 on the road, or to start the ownership process over again with something new.

Anza Borrego GL 2014-01

I’m not really crazy about the idea of buying a new tow vehicle. The GL is in excellent shape overall (thanks to lots of new parts and meticulous maintenance), and let’s face it, tow vehicles are expensive.

But neither am I crazy about our tours of America becoming tours of Mercedes service centers.  This summer we were forced to visit dealership service centers in Pennsylvania, Washington, Oregon, and California, and that’s a reminder to me that the trusty steed is no longer a youngster.

For now I’m choosing a third option: Do-It-Yourself (DIY). It’s impractical for me to do large repairs on the road but while we are parked at home base over the winter I have the opportunity to do routine maintenance and certain repairs in the driveway. The Mercedes “Service B” interval costs about $500-700 when done at a dealership; last winter I did it myself for about $150.  In October I replaced the rear brakes for about $220 in parts and supplies, which was about 1/3 what the dealer would charge.

Not only is DIY a big savings but it is an interesting opportunity for personal growth. For most of my life I would have described myself as “not mechanically inclined.” That was my father’s special ability, not mine. But entering the world of Airstreaming gradually forced me to pay attention to how things worked, and ask questions, and acquire tools & skills.

It has been frustrating at times. There have been many times when I would never have persevered without the support and advice of friends like Nick, Colin, Brett, and Super Terry. When a vital part slipped from my fingers and disappeared, when I accidentally cross-threaded a bolt in the engine block, when I mis-wired something and blew up part of a circuit board, when the wheels literally came off the Airstream … all those times when it seemed there was absolutely no hope and I was about to drown in self-doubt or confusion, my friends have been there to help me get perspective.

One of the places where I buy parts, Mercedessource.com, provides a single Lemonhead candy in many of their parts kits. This is so you can “seek the wisdom of the Lemonhead” when things get difficult. In other words, step away from the problem for a while. In those moments of frustration when things seem bleakest it’s extraordinarily helpful to simply stop working and let your emotional chemicals subside. I usually go seek advice from friends or reliable documentation for a while. Eventually the path forward becomes clear—and the problem that seemed so utterly impossible before gets resolved.

Over the past ten years this learning process has been so empowering for me that it has literally changed my life. I’m still cautious about tackling new mechanical or electrical things (because the more you learn, the more you realize how much you don’t know) but the knowledge and confidence I have gained has led me to things like:

I look back on those accomplishments with amazement, because ten years ago I would never have seen myself doing any of those things. If you’re thinking the same about yourself, well, don’t sell yourself short.  You can learn anything.

And it feels great to have more self-sufficiency.  Most of us are constant victims of our modern “disposable” consumer products system.  The system says that more durable items (appliances, vehicles) must be serviced only by a qualified technician, and like our semi-broken healthcare system, you aren’t allowed to question the cost.

Well, that’s baloney. Sure, I can’t DIY every car repair. I don’t have all the tools or all of the abilities. The dealership service centers are still collecting their toll from me every year. But we can all push back on the system a little, empower ourselves, reduce inconvenience, and avoid being chumps if we bother to understand how things work and take some time to do what we can by ourselves.

I almost lost my resolve over the latest car issue.  The “Check Engine” light had popped on again, this time indicating a failure in the Diesel Exhaust Fluid (DEF) treatment system.  The dealer quoted $2,400 to fix this problem and (on top of several other expensive repairs earlier in the year) that was enough to make me seriously consider pitching the car in a river and signing up for a new car loan.

A technical aside here: DEF is a fluid that gets injected into the exhaust stream to combine with nitrogen oxides chemically to produce much cleaner exhaust.  The output turns into water vapor and free nitrogen. Mercedes calls DEF “Adblue” when they are feeling romantic (e.g., selling cars) and they call it “reductant” when they are feeling technical.  Whatever, it’s all the same thing: a mixture of dionized water and 32.5% urea.

The problem with this stuff is that it freezes when it gets below 12 degrees F, and it crystallizes if exposed to the open air. So to comply with Federal emissions requirements which say that the system must work under all conditions, Bosch designed a fancy system that keeps the DEF warm and sealed. Then they sold this system to a bunch of car manufacturers.

While I’m all for clean air, the DEF system has been a hassle. We’ve had nearly a dozen incidences of “Check Engine” lights attributable to this system over the past eight years, requiring numerous overnight stays at the dealership while the engineers back in Germany huddled together to figure out yet another software update or component upgrade. The frequency of these problems has not decreased with time.  In fact, this summer we had to stop in Pennsylvania to replace a failing NOx (nitrogen oxides) sensor for $600, so this the second emissions-related Check Engine light this year.

When the Mercedes service center said it would be $2,400 for a new DEF tank heater, I began to weaken. It seemed to be too complex a job for me to tackle. Perhaps it would be a good idea to start over with a new car warranty (and massive new car payment).  My doubt began to grow. Then I did a little research and was reminded:

  • trade-in or resale value of our existing car would be ridiculously low.  I wouldn’t sell it for the going rate of about $13,000—it’s still a nice car!
  • the new diesel I’d want is temporarily off the market thanks to fallout from the VW/Audi scandal.  All the manufacturers are being very cautious right now.
  • if I could get a few more years out of the GL, there might be interesting electric vehicle options.  The electric car industry is rocketing forward and it’s not unrealistic to expect major developments in the next 5 years. Then I’d be free of these nightmarish emission-control systems and “Check Engine” lights.

With that bit of Lemonhead perspective, I dug in to the expensive repair I’d been told was needed.  It turns out that the service center solution for a failing DEF tank heater is to replace the entire tank, pump, heater, and temperature sensor as a single unit. The heater is not offered as a single replacement part.

I can see why they do that. Removing the whole thing is a pretty easy job, taking about 60-90 minutes.  Drain the tank, remove eight bolts, disconnect a few wires and a hose, then pull the tank out and swap in a new one.  A dealership technician can do that quickly and not worry about the customer coming back for another problem in the same system, since everything has been replaced. And happy-happy-joy-joy, the dealer makes a pile of money charging $1,800 for the tank and about $600 for labor and supplies.

Adblue tank connections

On the other hand, replacing the heater alone is cheaper but requires some additional work for disassembly, a few more tools, soldering, etc.  That’s the kind of thing I can do myself if it saves a pile of money. I found a company that sells an upgraded version of the tank heater for $300, and with some help from Nick, installed it in a few hours. Eleanor helped me re-assemble the car afterward. Bottom line: The “Check Engine” light is off and all is well.

It’s funny how the elimination of that little fault indicator can suddenly make the car seem like new again. Having the satisfaction of fixing it myself (and saving a pile of cash) makes it even better. I took the GL out for a test drive and everything is humming along just as it should.  Now I’m perfectly happy with the GL—why was I ever considering selling it for a pittance and taking on a massive debt load?

Anza Borrego GL and Caravel 2014-01

In the next week or so I’m going to tackle a major Airstream electrical upgrade with my friend Nate. It’s the kind of thing that an electrician could do for $500 or so, but by doing it myself I know it will be done exactly the way I want—and once again I’ll probably learn a few things (from Nate) in the process.  You can read about it here soon.

Comments

  1. David B Johnson says

    Most excellent. There is an old saying where I come from: Don’t judge a person by what they have, judge them by what they don’t need. Being independent and self sufficient was an important attribute. You are well on your way.

    David

  2. Robin Moeller says

    Ah yes, DEF Fluid, the bane of our existence. It took two weeks and $1500 for the GM Dealership to fix our GMC Sierra 3500HD. On the way home from a trip, we got the dreaded “you have 100 more miles to drive 65 MPH”, and so on. We barely made it home and had to have the truck towed to the dealership because the computer refused to let us drive any farther. Thankfully we weren’t towing at the time. I think there is something inherently wrong about a system that prevents you from driving your $60K vehicle because of emissions equipment.