The differentials on your Ford, Chevrolet, or Dodge diesel pickup are some of the hardest working components on your truck. At Harold's Used Auto Parts Inc in Philadelphia, PA, our technicians are experts in maintaining, repairing, and replacing differentials, keeping your truck reliably on the road.

If you drive a diesel vehicle, it’s because you know that quality matters. At Harold's Used Auto Parts Inc in Philadelphia, PA, we built our reputation on quality. We chose to work on quality products because it’s something that we ourselves believe in, and strive for daily.

At Harold's Used Auto Parts Inc in Philadelphia, PA, we have the facilities, equipment, and technicians necessary to complete any job, no matter how big or small. When it comes to fleet and diesel trucks, the right people with the correct equipment makes all the difference - we’ll keep your truck reliably on the road, and we’re the fastest, most efficient repair facility in the business. When it comes to trucks this size, and this valuable, cut-rate maintenance and repair simply won’t do; you need professionals, with the tools and equipment necessary to get the job done right.

Whether you drive a Ford, Chevy, or Ram diesel pickup, it’s especially important that you always seek high-quality repair and maintenance from qualified professionals. At Harold's Used Auto Parts Inc in Philadelphia, PA, we specialize in diesel vehicles and the ins and outs of diesel servicing. There are plenty of shops out there that can replace a part or perform a job, but it’s important that the technicians doing the work know what they’re doing, why they’re doing it, and are doing it right.

Whether you drive a Chevy, Ram, or Ford diesel pickup, we have you covered. At Harold's Used Auto Parts Inc in Philadelphia, PA, we can do it all - and a big part of that is done by employing ASE certified technicians.

At Harold's Used Auto Parts Inc in Philadelphia, PA, we know your Ford, Chevrolet, or Dodge pickup was designed for optimal power, torque, and towing and hauling ability, no matter what the job is. We also know that while getting up to speed in a timely fashion is important, your diesel pickup’s ability to stop is equally essential.

At Harold's Used Auto Parts Inc in Philadelphia, PA, our objective is to keep your diesel truck on the road, where it belongs. Whether it’s maintenance, repair, or information that keeps you from needing a repair, we do our best to keep you informed on how to best take care of your diesel truck. Cavitation is a leading killer of diesel engines. It’s an interesting process, albeit an expensive one if your diesel engine is a victim of cavitation. From our team here at Harold's Used Auto Parts Inc, here's what you should look out for:

Obviously, your fuel delivery system is an extremely important aspect of the running condition of your truck. At Harold's Used Auto Parts Inc in Philadelphia, our expert team of mechanics can treat and clean your fuel delivery system, ensuring you get the most out of your fleet.  Keeping the fuel system clean is essential, particularly with high mileage diesel engines. Sediments and carbon buildup can dramatically affect pumps, filters, lines, and injectors. There are many important reasons to have your fuel system regularly checked and cleaned.

At Harold's Used Auto Parts Inc in Philadelphia, PA, our technicians have a wide variety of top of the line tools and equipment available to diagnose and repair your Chevrolet, Ford, or Dodge diesel pickup. We utilize equipment at the forefront of technological innovation to best provide for the specific needs of your truck.

In the diesel world, "blow-by" is a term you’re bound to run across at some point if your line of work involves diesel-powered vehicles of any kind. What is blow-by, what causes it, and how concerned should you be? At Harold's Used Auto Parts Inc in Philadelphia, PA, our fleet maintenance and diesel technicians see it on a regular basis. Here we’ll take a quick look at blow-by, correcting it, and preventing it.

In the diesel world, "blow-by" is a term you're bound to run across at some point if your line of work involves diesel-powered vehicles of any kind. What is blow-by, what causes it, and how concerned should you be? At Harold's Used Auto Parts Inc in Philadelphia, PA, our fleet maintenance and diesel technicians see it on a regular basis. Here we'll take a quick look at blow-by, correcting it, and preventing it.

What is Blow-By? - Diesel blow-by is a term that describes an event of lost compression into the crankcase. Blow-by occurs whenever a burnt or unburnt fuel and air mixture escape from the cylinder and past the piston rings and into the crankcase. In a perfect world, the piston would be sealed tightly in the cylinder, able to move up and down but keeping all the air and fuel and exhaust that enters or exits the cylinder during the combustion process out of the crankcase. As you'll see, this perfect world doesn't exist, but it is important to minimize the amount of blow-by in a diesel engine.

On gas engines, the fuel delivery system is pretty simple - an electric pump draws gas from the tank, and pushes it to the injectors. Diesel systems are a little more complex. At Harold's Used Auto Parts Inc in Philadelphia, PA, we like to keep you informed about what’s on your truck, how it works, and how to maintain it, so you stay reliably on the road.

Diesel engines are known for their reliability - that’s probably at least partially why you bought one. However, like all things, diesels and their components wear out eventually. Fortunately, the technicians at Harold's Used Auto Parts Inc in Philadelphia, PA have you covered. Here are some fuel system issues to watch out for.

Now that you’ve got an idea of the components that make up a diesel system, and what they do, understanding how the system works in a more cohesive way isn’t difficult. At Harold's Used Auto Parts Inc in Philadelphia we understand what’s going on in your fuel system while your diesel engine is running.

Good diesel technicians and shops that service diesel engines are hard to come by. At Harold's Used Auto Parts Inc in Philadelphia, PA, diesels are our specialty. There are many reasons to have diesel truck maintenance performed by diesel specialists - here are just a few.

When it comes to installing new tires on your Dodge, Chevy, or Ford diesel pickup, you want it done right the first time. Our technicians have the equipment necessary to get you cruising smoothly down the road in no time.

Whether you drive a Ram, Chevy, or Ford diesel pickup, our expert technicians have the know-how you need - from trivia to engine rebuilds, we’ve got you covered.

Increasingly, technology in automobiles is becoming more sophisticated, and more and more systems have become reliant on electronic control modules to operate. At Harold's Used Auto Parts Inc in Philadelphia, PA, we have the trained technicians and the equipment necessary to deal with issues that arise as a result of these components.

The engine in your Chevrolet, Dodge, or Ford diesel pickup is the heart and soul of your truck. At Harold's Used Auto Parts Inc in Philadelphia, PA, we repair, rebuild, and replace engines with quality parts and builds, keeping your truck on the road for years to come.

At Harold's Used Auto Parts Inc in Philadelphia, PA, maintaining your fleet and keeping your business reliably on the road is our primary focus. As trucks wear out, and they always do, you will inevitably be faced with this dilemma - “Should I fix this truck, or replace it with a new one?” This isn’t always an easy question to answer. As your fleet specialists, our team here at Harold's Used Auto Parts Inc is here to help you decide.