Heavy Duty DIY Repairs (Explained)


volvo engine

In this blog I am going to cover some helpful information about DIY repairs for your heavy-duty truck. It doesn’t matter if you are driving a Volvo, Mack, Freightliner, Peterbilt, Western Star or Kenworth truck, the knowledge below can apply to any class 8 heavy duty chassis.  

Doing your own repairs can help you take control of your truck's uptime, saving you time and money compared to visiting repair shops. 

The more you know about your truck the better equipped you will be to know when something is wrong. When you start performing DIY repairs you will discover more about your truck and how it operates with different components.  

We broke down heavy duty DIY repairs in 3 different categories.  

  • Level 1 - Beginner  
    • This level of repairs will not require to you to have extensive mechanical knowledge. It does, however, require some basic tools for you to have on hand. 
  • Level 2 - Intermediate  
    • These repairs require you to understand more about your vehicle, which will help you troubleshoot your repairs quickly. 
  • Level 3 - Expert
    • At this level you will be doing almost all of your own repairs. This would require you to learn the most about your vehicle. It is recommended to have a toolbox or tool chest with all the required tools to perform the work.   
It doesn't matter if you are a beginner, intermediate or expert DIY'er, you can do the following 2 things to save upwards of $1,000+ / year. 
  • Self-Diagnosing - CEL / Check Light / Fault Codes  
    • Look up Check Engine Light  
      • Figure out what is causing the light and use that knowledge to perform the repairs.  
      • Look up wire diagrams to aid you in your repair.  
      • You will need to have a scan tool, such as OTR Diagnostics or OEM software to look up your fault codes. 
  • Perform Monthly DPF Regenerations 
    • Preventive maintenance to ensure DPF filter is cleaned. 
    • Requires you to have a scan tool, such as OTR Diagnostics or OEM software. 

HD DIY Truck Repairs - Beginner  

These types of repairs require basic tools, and you won't need extensive repair knowledge. If you have never tackled these before there are many helpful videos on YouTube to walk you through them.  

Potential Savings: $2,500+ / year 

  • Windshield wipers
  • Light bulbs - headlight, taillight, and turn signals
    • Requires basic tools
  • Gland hands replacement / seal 
  • Mud flaps 
  • Batteries 
  • Blown fuses  
  • CB radio install 
  • Air filter  
    • Requires basic tools 
  • Sensors  
    • Requires basic tools 

HD DIY Truck Repairs - Intermediate 

These types of repairs require more of an investment of your time and equipment. This is for when you want to do as many repairs as possible and you’re only taking your truck to the shop for larger repairs.  

Potential Saving: $10,000+ / year   

  • Replacing fluids, this includes engine oil, engine oil filter, engine fuel filter 
  • Replacing transmission oil, differential oil 
  • Replacing air dryer filter 
  • Replacing failed components that were diagnosed to be an issue. You can usually find out what is causing the issue based on checking your fault codes.  
    • Nox sensors, DPF temperature sensors, DEF sensors, EGR sensors 
  • Replacing DEF fluid 
  • Replacing air lines  
    • Replace brass couplers 
  • Replacing suspension air valve  
  • Replacing alternator, belts 
  • Replacing exhaust piping or flex pipe 
  • Blower motor, blower motor resistor 

HD DIY Truck Repairs - Expert 

These types of repairs require extensive heavy duty knowledge. This is where you are going to invest the most amount of time, but the cost savings are also the highest. This is for when you want to perform all of your own maintenance on your vehicle and you will resort to going to a shop if the level of complexity revolves around a dealer only item. 

If you are going to be doing these types of repairs it would be ideal to have a large garage or barn to store all of your tools. 

Tools you’ll potentially need 

  • Air compressor, jack, jack stands, all HD specialty tools, hand tools, and air tools.  

Potential Saving: $20,000+ / year 

  • Replacing any component under your engine valve cover.  
    • Injector replacement 
    • Overhead adjustment 
    • Fuel Pump 
    • Timing Cover 
    • Oil Leaks 
    • Water Pump 
    • Camshaft 
  • Exhaust Components 
    • Exhaust manifold 
    • Turbo charger 
    • Aftertreatment Fuel Injector   
  • Performing any removal of any major engine / drivetrain components 
    • Starter  
    • Engine replacement 
    • Radiator  
    • Clutch Fan 
    • AC Condenser  
  • Performing any removal or replacement of any aftertreatment component. 
    • EGR valve 
    • EGR cooler 
    • DOC filter 
    • DPF filter 
    • SCR catalyst filter 
  • A/C System 
    • AC compressor 
    • Recover, vacuum, recharge system 
    • Replace any hose or line 
  • Steering shaft seal, steering box, steering shaft 
  • Transmission  
    • Replacing clutch 
    • Replacing XY shifter  
  • Suspension  
    • Replacing springs 
    • Bushings  
  • Axles  
    • Wheel seals  
    • Wheel end - axles 
    • Wheel bearings  
    • Wheel hub   
  • Brakes 
    • Brake drums / pads  
    • Brake disc / pads 
    • Wheel speed sensors  
  • Fifth Wheel 
    • Replacement  
    • Rebuild kit 
  • Air System 
    • Air Bags - front / rear Suspension 
    • Air Bags - cab / chassis 
  • Electrical  
    • Engine 
    • Transmission  
    • Chassis wire harness repair  

No matter how far you want to dive into doing your own truck repairs you’ll be saving money in the end. This is why we recommend doing at least the most basic maintenance yourself, helping keep your cost down and profits high. 

Let us know if we can help you! We are more than happy to offer help just give us a call at 586-799-4375 

As always, be blessed and stay safe!  

Looking to learn more? Check out our other blog posts. 

    OTR Diagnostics allows you to read and reset fault codes, view live data, and run advanced diagnostic functions, including forced DPF regen with your mobile phone or tablet. Select which engine you have for your diagnostic package. 

    The OTR Reset Tool is specific to which model and engine you have. Select which engine for more specific details. 


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