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Posted on February 14, 2025April 30, 2026 by David Ley

Diesel Turbocharger Sounds: What They Mean and When to Inspect

A diesel turbocharger is not silent.

A light whistle, whoosh, or spool sound under load can be completely normal. However, when the sound changes suddenly, gets louder, or comes with smoke, low power, or oil consumption, it can point to a problem in the turbocharger system.

The key is not just hearing the sound.

It is understanding what kind of sound it is, when it happens, and what else the engine is doing at the same time.

Turbocharger noise can come from the turbo itself, but it can also come from boost leaks, exhaust leaks, restricted air filters, fuel system problems, damaged exhaust components, or lubrication issues. Garrett specifically notes that noisy performance, low power, smoke, and oil consumption can come from underlying engine problems—not always the turbocharger itself.

Posted on February 7, 2025April 30, 2026 by David Ley

Diesel Cylinder Head Cracking: 4 Causes, Symptoms & Prevention

Diesel cylinder head cracking is one of the most serious issues an engine can face – and one of the most expensive if it’s not caught early.

What makes it worse is that it often starts small.

A minor overheating event, a stress point in the casting, or an installation issue can eventually turn into coolant loss, compression problems, and complete engine failure.

Understanding what causes cylinder head cracking – and what to look for – can help prevent repeat failures and unnecessary downtime.

Posted on January 24, 2025April 30, 2026 by David Ley

Why Correct Fuel Injector Trim Codes Still Result in Poor Engine Performance

You’ve replaced the injectors.
You’ve programmed the trim codes correctly.
Everything checks out – and the engine still runs rough.

This is more common than most people realize.

Fuel injector trim codes are designed to fine-tune fuel delivery, but they are not a fix-all. If the engine is still underperforming, the issue is almost always outside the trim code itself.

Posted on January 11, 2025April 30, 2026 by David Ley

Low Boost Diesel No Check Engine Light: Causes and Diagnosis

If you’re dealing with low boost diesel no check engine light, you’re not alone.

This is one of the most common complaints we hear.

It’s also one of the most misdiagnosed. And because there’s no fault code, it’s easy to assume:

The issue isn’t serious
It’s electrical
Or nothing is actually wrong

In reality, low boost with no warning light is usually a mechanical or system efficiency issue.

Posted on January 1, 2025April 30, 2026 by David Ley

Bosch High Pressure Diesel Oil Pump: Signs of Failure and the Benefits of a Replacement

Is your Navistar/International DT466/I530 HEUI High Pressure Oil Pump showing signs of reduced power, decreased fuel economy, increased emissions, or rough running? We can help you recognize the signs of failure and inform you on all of the benefits of replacing your oil pump with a Genuine Bosch oil pump from HHP.

Posted on January 1, 2025April 30, 2026 by David Ley

Why Your Caterpillar C15 ACERT Turbocharger Might Not Be the Real Problem

If you’re dealing with low power, smoke, or oil around the turbo on a Caterpillar C15 ACERT, it’s easy to assume the turbocharger has failed.

But that’s not always the case.

At Highway and Heavy Parts, we see this all the time – turbos get replaced, but the original problem is still there. That’s because many turbo “failures” are actually symptoms of fuel system issues, oil problems, or internal engine wear.

Before replacing your turbo, it’s critical to understand what’s really going on.

Posted on January 1, 2025April 30, 2026 by David Ley

Why Intake Valve Seats Fall Out In Diesel Cylinder Heads After Overheating

A dropped valve seat in a diesel engine isn’t just a cylinder head issue – it’s a direct result of thermal stress, material expansion, and loss of interference fit.

This type of failure is most commonly seen after an overheating event, and once it happens, the damage is usually severe enough to require cylinder head replacement and, in many cases, piston repair.

Understanding why valve seats fail – and what leads up to it – is critical to preventing repeat engine damage.

Posted on September 3, 2024December 3, 2025 by David Ley

Dinex Emission: The Solution to Diesel Pollution

Dinex Emission is a company that has been dedicated to helping diesel operators meet the high standards of the EPA for a very long time. Though the EPA’s goal is to reduce the emissions of dangerous gasses into the air, their restrictions can often make transporting goods, completing construction projects, and harvesting large crops more difficult. As an expert in the field of diesel emissions control, Dinex has long been the solution to this obstacle.

Posted on May 2, 2024April 15, 2026 by David Ley

Common Diesel Engine Problems and Solutions

Diesel engines are workhorses, powering everything from trucks to heavy machinery. However, like any complex machinery, they can encounter problems. Let’s explore some of the most common issues and their solutions:

Posted on January 1, 2024April 22, 2026 by David Ley

Symptoms Your Common Rail Fuel Injectors Are Failing

No matter if you are a rookie or an experienced mechanic, mistakes do happen. Maybe your mind isn’t in the right place or maybe you were distracted when putting on that last valve cover. Whatever the reason, improperly installing a gasket will result in a leak almost every time.>

Posted on September 15, 2023 by David Ley

Diesel Engine Break In Procedure

We often get calls about the break in procedure of a newly rebuilt engine. Proper break in is critical and sometimes overlooked. Even though you may have used one of our outstanding overhaul kits and your mechanic did a great job installing the parts, if the engine is not broke in correctly, the rings may not seat. This will lead to oil consumption and power loss.

Posted on September 19, 2022 by David Ley

DT466E and DT530E O-Ring Change

Through the years, diesel engines have undergone some major changes. Sometimes, the changes happen from model to model, but at other times, updates will be made to existing engines.