2018 Mercedes-Benz GLS450 Engine Makes A Ticking Noise

Ticking Noises in 2018 Mercedes-Benz GLS450 Engine: Causes and Solutions

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Reviewed by
Bo Fader
Written by RepairPal Car Genius
Updated January 14, 2025
0%
12% chance it's the
Exhaust Leak
0%
88% chance it's
Something else
The most common reasons a 2018 Mercedes-Benz GLS450 engine makes a ticking noise are low oil level or pressure, an issue with the ignition system, or an exhaust leak.
  • Exhaust Leak: A damaged exhaust manifold or a loose connection in the exhaust system can cause an exhaust leak, resulting in increased noise and potential loss of engine power.
Proper diagnosis will determine the exact cause of your symptom, saving you money on unnecessary repairs. The diagnostic experts at RepairPal Certified shops have the right tools and experience to solve any symptom.

How much does it cost to fix a 2018 Mercedes-Benz GLS450 engine makes a ticking noise?

Common Repairs

The total repair cost will vary based on the condition of your vehicle and the number of repairs needed to fix your symptom. Proper diagnosis will save you money by finding the exact repairs needed to fix your car right the first time.

If the drive belt idler pulley fails, there will be a very audible chirping noise from the front of the engine. This is because the idler pulley bearing is no longer smooth, and rotating causes metal to grind at high speeds. If it is not changed immediately, there is a chance it will become dislodged, or allow the drive belt to slip off. If the belt falls off, the accessory that it drives will no longer function. For instance, if the alternator belt idler pulley fails, the alternator may stop functioning. Also if the pulley begins to wobble, allowing slack in the belt, it will make an extremely loud squeaking or screeching noise, especially on cold starts. This is the belt slipping on the crankshaft pulley, and will require belt replacement once the idler pulley is replaced.

If the drive belt tensioner fails, there will be a very audible chirping, grinding, or rattling noise from the front of the engine. This is because the tensioner pulley bearing is no longer smooth, and rotating causes metal to grind at high speeds. If it is not changed immediately, there is a chance it will become dislodged, or allow the drive belt to lose tension, or break. If the belt falls off, the accessory that it drives will no longer function. Also, if the tensioner spring fails, allowing slack in the belt, it may make an extremely loud squeaking or screeching noise combined with a rattle as the tensioner bounces back and forth under load. The squealing noise is the belt slipping on the crankshaft pulley, and will require belt replacement once the belt tensioner is replaced.

An engine leaking oil does not always make a puddle on the ground. A burning smell may be noticed from the front of the vehicle after driving. This is because engine oil leaks may fall onto hot engine components, especially the exhaust manifold, and burn off before making it to the ground. This poses a risk to the engine because the leak going unnoticed may deplete the engine oil reserve, and lead to an oil starvation issue. Some engine oil leaks only occur while the engine is running, so the leak may be larger than the small spot on the ground makes it seem.

Noises can be accompanied by many annoying or worrisome sensations. Consider the noise of grinding brakes, the noise sounds much like the brake pedal and steering wheel feel. This is important, as random noises can be difficult to replicate without knowing when the sound occurs, what must be done to make the sound, and what sound it is. Any professional technician can replicate and diagnose most noises, but to ensure the vehicle is more quickly diagnosed, make sure you tell your technician these three pieces of information.

The engine oil pressure warning light will come on if the engine oil pressure is low, or if the oil pressure sensor is faulty. In either case, engine power may be reduced significantly. The check engine light may also illuminate, and an on-board diagnostic (OBD) trouble code will be stored in the vehicle's computer.

What are the potential causes of a ticking noise in the engine of a 2018 Mercedes-Benz GLS450, and how should I diagnose them?

When diagnosing a ticking noise in the engine of a 2018 Mercedes-Benz GLS450, it's crucial to follow a methodical diagnostic approach that begins with the simplest checks. Start by verifying the engine oil level, as insufficient oil can lead to poor lubrication of engine components, resulting in ticking sounds. If the oil level is adequate, proceed to inspect the valve train for any signs of wear, particularly focusing on the lifters and valves, which are common culprits for such noises. Next, examine the timing chain or belt for any looseness or wear, as these components are vital for maintaining proper engine timing and can produce ticking if they are compromised. Additionally, check the condition of the spark plugs, as faulty or worn plugs can also contribute to ticking noises. It's also important to inspect the exhaust system for any leaks near the engine, as these can manifest as ticking sounds. If these preliminary checks do not reveal the source of the noise, it may be prudent to seek the assistance of a professional mechanic who can employ specialized tools and expertise to accurately diagnose the issue. By adhering to this structured approach, you can effectively identify and resolve the ticking noise in your vehicle's engine.

What could be causing the ticking noise in the engine of a 2018 Mercedes-Benz GLS450?

When diagnosing a ticking noise in the engine of a 2018 Mercedes-Benz GLS450, it's crucial to consider several common problems that could be the source of the issue. One of the primary culprits is valve train issues, which may arise from worn lifters or malfunctioning valves, leading to irregular engine sounds. Additionally, a low oil level can significantly impact engine performance, as insufficient lubrication can cause components to rub against each other, resulting in a ticking noise. Another potential cause is a faulty timing chain tensioner, which may fail to maintain proper tension on the timing chain, creating an audible ticking sound. An exhaust leak, particularly near the engine, can also manifest as a ticking noise, as escaping gases create irregular sounds. Lastly, spark knock, which occurs when the air-fuel mixture ignites prematurely, can produce a distinct ticking or pinging noise. To effectively address these issues, it is advisable to consult a qualified mechanic who can accurately diagnose the problem and recommend appropriate repairs, ensuring the longevity and performance of your vehicle.

How urgent is it to address the ticking noise in the engine of a 2018 Mercedes-Benz GLS450?

Addressing a ticking noise in the engine of a 2018 Mercedes-Benz GLS450 is crucial for maintaining the vehicle's overall health and safety. Ignoring this symptom can lead to severe consequences, including extensive engine damage that could result in costly repairs. Early detection is key; by identifying the issue promptly, you can mitigate the risk of further complications. Additionally, addressing the noise not only helps in preserving the vehicle's performance but also ensures your safety on the road, as unresolved engine issues can lead to unexpected breakdowns. If your vehicle is still under warranty, timely action is even more critical, as delays might affect your coverage for necessary repairs. For those considering a DIY approach, it is advisable to conduct a thorough inspection or consult with a qualified mechanic to accurately diagnose the problem and determine the best course of action. Taking these steps will not only enhance your vehicle's longevity but also provide peace of mind while driving.

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