Stop Reacting to Breakdowns and Start Avoiding Them

Most of our shops handle preventative maintenance programs reasonably well in terms of oil changes, brake linings, and possibly even things like diesel particulate filters and automatic transmission services.  But what about other items that fail at a relatively similar rate such as DOC (diesel oxidation catalyst) inlet or outlet valves and NOx sensors.  These items are an integral part of the emissions control systems and are common causes of on the road repairs.  There are some reasonably inexpensive ways to move from being reactive to proactive.

Step 1 – Collect Your Data

The first way is by simply examining your repair records for patterns.  For example, have you recently seen a string of a certain component failing?  Have you had several on the road breakdowns all with a certain make of truck or engine?  At a minimum you should be keeping a spreadsheet tracking each breakdown, what components failed and at what mileage.  Even better is to have a report set up in your maintenance tracking program that will pull this information for you as well as things like truck make and model as well as engine make and model.  In fact, if your maintenance program does not have such a report you should consider either getting them to create one or hire a programmer to do it yourself.  Ideally, you should be able to tabulate the reasons for the breakdowns and what failed.  Include both on the road repairs and any work you did inhouse.

An additional step you will want to track is how much each breakdown costs you – did you need to put a driver up in a motel, did you need to rent a replacement tractor, was a tow required, or did you just have to pay that driver to sit while the repair took place.  Also include a per day rate for just having the equipment not being utilized – it may not be an out of pocket cost, but your company still incurred it.

Finally, you may have new equipment that you have not previously bought, or you may not have enough data on to make an informed decision on.  In this case networking with other fleets to determine failure rates and approximate mileages will have to suffice.  Other sources of information would be your dealership, a local maintenance association, attending a TCA convention or event or meetings of your state trucking association.

Step 2 – Evaluate Your Findings

Now that you are armed with this data, what do we do with it?  The first thing you are going to do is to start with your 4 or 5 most common failure points.    By focusing on a few common items, you can keep things manageable.  Next do a root cause analysis as to why those components failed.  For example, if you have a specific sensor that regularly fails do you tend to see a specific reason for that failure – say a damaged wiring harness or is it general wear and tear.  In this example, if it is a damaged wiring harness then ensure that your PDI service for that engine includes something like installing additional wire loom around that harness.  If a simple modification is not apparent, then look for trends as to when the component fails – either by time or by mileage.

Step 3 – Develop an Action Plan

Using our sensor example again, let us assume that there is no discernable reason why it fails, but you can see that the failures mostly come in a range between 200,000 and 225,000 miles.  This failure generally affects 50% of your tractors.  Please note that your costs may vary, and these are purely for illustration purposes:

Repair Costs:

Sensor                                  $200

Labor (1hr @ $100/hr)   $100

Total                                      $300 per vehicle


Breakdown Costs:

Tow                                       $400

Motel                                    $80

Meals                                    $20

Layover Pay                        $100

Staff Time (1.5hr)             $75

Lost Utilization                  $200

Total                                      $875


Normally when this sensor fails it is covered under warranty.  While I normally would not recommend forgoing warranty dollars, in this case it may be more cost effective to replace the sensors proactively. In this example each replacement would cost $300 and only half of the tractors incurs a failure, so you are spending $600 in replacements for every failure.   Regarding the lost utilization cost, the vehicle was down and not creating revenue for 24 hours at a cost of $200 per day (this will vary based on the purchase price, the term of the loan, etc.).  Overall each breakdown is costing you $875 between out of pocket and implicit costs.  At $600 to cover the replacements needed to avoid a single breakdown you have an immediate payback to give up the warranty dollars and do a proactive replacement.

Once an action has been determined to be economical, create a proactive program that will be applied to coordinate with a preventative maintenance point. Ensure that your technicians are aware of the required repairs and provide any necessary training.

Step 4 – Follow up, Evaluate the Program and Look for any Improvements

They say that the proof is in the pudding and in this case the proof is measured in a reduction in breakdowns caused by the component you are proactively replacing.  This is a step many of us neglect.  However  However, without it you can’t properly determine if the program delivered.  If you reduce the failure rate to 10% then you can call the program a success.  However, if the failure rate barely changes then you need to go back and look for something that the first analysis missed.  Regardless of the results you should redo your root cause analysis to determine if there are any further steps that pass the cost-benefit test.  Continue to look to other sources to see if the manufacturer has made any changes that require a change in the trigger point for the program – a new design may not fail until 300,000 miles meaning that an extended interval will result in fewer replacements per year and lowering your costs.

Finally continue to review your breakdowns and repairs to update your top five to ensure that you are keeping up with any changes in technology and stay ahead of the curve.