The Truck Shop -
Mobile Diesel Mechanics

#1 Mobile Truck Repair by Virginia’s Best Certified Mobile Diesel Mechanics

Road Runner Wrecker Service provides mobile truck repair services for the Fairfax County and Loudoun County areas. Regardless of your issue, Road Runner has the mobile diesel mechanics to get you back on the road immediately. We will do everything we can to repair your truck on the spot, without having to tow your vehicle.

Road Runner is here for the long term. Our focus on customer service and attention to detail make us the go-to company for anyone in need of heavy duty towing or mobile truck repair. Over 90% of the surrounding county governments use Road Runner. Give us a call today and see how we can help you.

Mobile Truck Repair Services for Loudoun County and Fairfax County:

  • Virginia State Inspections
  • Alignments
  • Mobile Scan Diagnostics
  • Air Brake System Repair
  • Annual Inspections
  • Cool System Repair
  • Drive Line Service
  • Heating System Repair
  • Differential Repair
  • Exhaust Repair
  • Steering Repair
  • Transmission Repair
  • Welding Services
  • Diesel Wheel Services
  • Filter Replacements and Preventative Maintenance

Mobile Scan Diagnostics

Has your check engine light suddenly gone on? Worried about hitting the road until you know what is causing it? Road Runner has you covered. Give our 24/7 emergency roadside assistance team a call at 703-450-7555 and we will have a team by your side in no time!
Our Mobile Truck Repair Service offers mobile scan diagnostics for a range of engines including, but not limited to:

  • Cummins
  • Volvo
  • Mack
  • Caterpillar
  • Hino
  • International
  • Isuzu
  • Ford
  • Chevrolet
  • Dodge

Check engine light mobile diesel repairs have a variety of causes and an even larger range of solutions. Some of the most common issues we’ve encountered that cause check engine lights are the following:

  • Lack of coolant. This is an easy fix and we will have you on the road again in minutes.
  • A clogged diesel particulate filter (DPF filter) sometimes requires forced regeneration. We will identify whether it needs a cleaning or a total replacement and take care of it for you.
  • A wide variety of general sensor issues including diesel exhaust fluid (DEF fluids).

Our Onsite Truck Diagnostics team is equipped with state of the art tools for any Fault Code Troubleshooting. Regardless of the fault code, they are ready for it!

No job is too difficult for Road Runner. We will always say yes!

Air Brake System Repair

Our team will inspect and make any necessary repairs to your air brake system. Included in the air brake system is compressor servicing as well as servicing and repairs of governors, dyers, fittings, lines, valves, hoses, chambers, and ABS systems. We leave no stone unturned during our inspection process.

Here are some of the steps we will go through during your repair.


The minimum operating pressure for an air brake system is no less than 100 PSI for a truck, and no less than 85 PSI for a bus.


We will monitor the time that it takes for the air pressure to rise from 85 PSI to 100 PSI at 600-900 rpm. This should take no longer than 2 minutes in order to pass inspection.


Road Runner will ensure that the correct cut-out governor pressure for the air compressor is between 120-135 PSI. They will then go on to ensure that the cut-in pressure is 20-25 PSI below cut-out pressure.This is merely a glimpse of our Air Brake Repair Services. Give us a call today at 703-450-7555 to learn more!

Drive Line Service

Our mobile truck repair service can repair drive lines on the spot. We will replace universal joints, u-joints, carrier bearings, yokes, drift shafts, and axles.
Should there be an issue with the transmission on your vehicle, we highly recommend bringing it to our in-house repair facility. Can’t make it to us? Call us at 703-450-7555 and we will pick you up!

Brake Service and Repair

We get it, you’re constantly on the road and your brakes eventually will get worn out. Road Runner maintains a large inventory of items to ensure that whatever is the issue, we have you covered. Need any of the following replacement parts? Give us a call today at 703-450-7555.

  • Brake Shoes
  • Brake Drums
  • Slack Adjusters
  • S-Cams
  • Break Chambers
  • Air Disc Brake
  • Rotors
  • Pads
  • Calipers
  • Chambers
  • ABS systems
  • Valves
  • Sensors
  • Air Lines
  • Air Hoses
  • Coil Hoses
  • Brake Chamber
  • Sizes: 16 brake chamber, 20 brake chamber, 24 brake chamber, 30/30 brake chamber, 30/30 short brake chamber. 30/30 long brake chamber, 30/36 brake chamber, 24/30 brake chamber

Don’t see your part on our list? No problem! We will get it for you.

Differential Repair by Certified Mobile Truck Repair Specialists

If you hear a noise coming from your differential, this can be a sign of insufficient lubrication. It could also mean that the gears and bearings have been worn out due to wear and tear. The Road Runner team can give you a full assessment and determine the best course of action.

While most of our truck repairs can be done wherever you are located, this particular repair would need to be done in-house at Road Runner’s repair shop. Problems with your differential can be extremely costly, let’s fix it before it gets to that point! Give us a call today at 703-450-7555 to set up an appointment!

Exhaust Repair Service

Most large cities subject vehicles to emissions testing. Failure to pass this emissions test will lead to you having to repair or completely replace your exhaust system. Our Mobile Truck Repair team will ensure that your vehicle will pass its emissions test!

Aside from the emissions test, a properly functioning exhaust system significantly improves your truck’s functionality. Your truck’s exhaust system is more complicated than you would expect. It involves exhaust manifolds, cylinder heads, oxygen sensors, catalytic converters, and mufflers. Failure of any of these components can result in a harmful impact on your gas mileage and environmental impact.

Our Mobile Truck Repair team can also help with exhaust brakes. The exhaust brake system will use the exhaust gas pressure to aid with vehicle braking. This system helps to ease the demands on your wheel brakes and therefore increase their total lifespan.

Radiator Service by Mobile Diesel Mechanics

Anyone who’s made a career on the road knows how frustrating overheating problems with diesel engines can be. Our Mobile Diesel Mechanics have seen it all, trust us! Diagnosing the cause of engine overheating takes skills and experience. Here are some issues that our mechanics will keep an eye out for:

Engine Coolant

The mobile diesel mechanics will first check your truck’s coolant level as this can often be an indication of a crack in the head gasket or the engine. Another cause is not as easy to see to the naked eye, air pockets. Air pockets in your system can cause a serious restriction of fluid flow and alter your coolant levels significantly.

Diesel Fuel Injector

Something as simple to clean as a build-up of deposits on the injector nozzle can cause the fuel injectors to malfunction. Your truck’s engine will need to work harder to compensate for the malfunctioning diesel fuel injectors which in turn will lead to overheating.

Cooling Fan

Our Mobile Truck Repair teams are professionally certified and will be able to quickly identify the underlying cause of a malfunctioning cooling fan. Be it a misaligned fan, a defective coolant sensor, or engine thermostat issues, our team will find it and have it repaired quickly.

Water pump

Our mechanics will keep an eye out for a faulty water pump issue. If they notice a pulley spinning faster than it should be, this is indicative that the water pump seals are wearing out. Clogs in the system can also cause water pump issues and lead to overheating.

No job is too difficult for Road Runner. We will always say yes!

Suspension and Steering Repair Services

  1. Suspension Air Bags
    The Road Runner Mobile Diesel Services team can repair suspension air bags. This will prevent swaying and leave you with a much smoother ride! We will analyze the suspension height sensors in order to properly calibrate them and have the proper air pressure settings for the flow between the compressor to the airbag.
  2. Leveling Valves
    We will inspect and repair any air suspension level control rods, front axle leveling, right side level valves, and left side level valves.
  3. Leveling Linkage
    The Mobile Diesel Repair team will ensure that your truck maintains the proper ride
    height by inspecting and repairing or replacing your leveling linkage.
  4. Air Lines
    We will thoroughly inspect the air lines supplying the air bags. Any signs of wear and tear will be addressed and reinforced. Should a replacement be the safest route, we will take care of that for you quickly and efficiently. Our mobile repair mechanics are qualified to work with lines from all brands, including Milton and Continental.

Transmission Repair Services by Mobile Diesel Mechanics

Transmission problems no longer have to be a headache for you with our certified truck mechanics. Our in-house experts will be able to diagnose the cause of those strange noises suddenly coming from your truck. Having trouble shifting gears?

Road Runner will find out why you’re suddenly revving between shifts or slipping gears while you’re driving. We will check for any transmission fuel leaks and also inspect the overall quality of your transmission fluid.

This job is done at our in-house truck repair shop. Contact us today and let us help you!

Diesel Wheel Services by Mobile Truck Tire Repair Specialists

  1. Bearings
    Road Runner’s mobile truck tire repair specialists can work with all types of bearings. We keep an extensive inventory so we are ready for any situation! Worn out wheel bearings won’t be able to handle a heavy duty load, contact us today to avoid any preventable accidents. From taper roller bearings to roller thrust bearings and ball bearings, we have you covered!
  2. Seals
    Worn out or warped seals can cause major problems. From allowing external contaminants in or letting precious lubricants out, damaged seals can be very costly. Our mobile truck repair specialists have all the tools to repair or replace your seals.
  3. Studs
    Wheel studs are the one thing attaching your wheel to the hub; without them, your wheels would go flying! Stripped wheel studs are extremely dangerous and should be replaced immediately. Call our 24/7 emergency roadside assistance team 703-450-7555 and let us get you back on the road safely!

Air Filter Replacement

Your air filters have numerous ways to let you know that they need changing! Here are some of them to keep an eye out for. If you notice any of these issues, please contact us today at 703-450-7555.

Signs that your truck needs an air filter replacement

  1. Reduced fuel economy
  2. Engine starting problems
  3. Excessive soot residue
  4. Black smoke and/or flames coming from the exhaust
  5. Check engine light
  6. Less horsepower
  7. Smell of gasoline
  8. Odd engine sounds and vibrations

Preventative Maintenance by Certified Truck Repair Specialists

We’ve all heard the saying “An apple a day keeps the doctor away”. The same goes for your truck. A visit to Road Runner for some preventative maintenance will definitely keep you safe and with more money in your wallet! We offer a multitude of preventative maintenance services including, but not limited to, fuel oil filter replacement, engine oil filter replacement, and chassis greasing.

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