New or reconditioned turbochargers for TDI engines - a comparison of advantages and disadvantages

New or reconditioned turbochargers for TDI engines from the VAG Group (VW, Audi, Skoda, Seat): An informative comparison of the respective advantages and disadvantages of the two options. The use of a purely used turbocharger is not discussed in this blog post, as it is absolutely not recommended. For VW T5 "Bulli" (Transporter, California, Caravelle, Multivan) in particular, the question of new or reconditioned turbochargers arises.

What does "reconditioned" turbocharger mean?

A overhauled turbocharger is usually based on a damaged used turbocharger from another vehicle, which serves as the basis for the overhaul. During the overhaul, only those components that are obviously damaged are replaced. These are usually the turbine wheels and the turbine shaft as well as the bearings that guide them in the housing. The housings on the exhaust side and the compressor side, on the other hand, are usually reused. Typical problems with such turbochargers can arise from the reuse of these housings or other components whose damage or wear has not been recognized:

• Material fatigue: Turbochargers are exposed to extremely high thermal loads. These stresses can lead to hairline cracks in housings or manifolds, which may go undetected or not be fully repaired during an overhaul. They often only become visible under prolonged thermal heating, which is not simulated in most test protocols.
• Limited customization options: Overhauled turbochargers usually have to work with the original components, which rules out optimizations such as larger bearing geometries.
• Long-term durability: Even with careful overhauls, there is still a risk that the material has already undergone ageing processes, which can result in cracking and poor properties a short time later.
• Housing dimensions: For the turbine wheels to function efficiently, it is essential that their distance from the inside of the housing is maintained as precisely as possible. When reusing used housings, it is often difficult to influence this critical distance, which means that the desired boost pressure is not achieved in certain operating ranges. VW T5 2.5 TDI drivers in particular are familiar with this issue: a slight rise in the road surface, an unfavorable position of the accelerator pedal and the vehicle goes into "emergency mode". After switching off and restarting the engine, the problem disappears. This is very often caused by the turbocharger. The control unit "expects" a certain boost pressure in a certain operating state, which the turbocharger does not reach at this moment. The result is an error message and the power-reduced emergency running program.

A brand-new turbocharger is not always better - it depends on the details

A brand-new turbocharger has the advantage that all components are unused and free from wear or material fatigue. However, there are other aspects that determine the quality of a turbocharger.

Unique turbocharger production at 07einsCustomized assemblies for optimum performance

07eins-Turbocharger are characterized by a special approach: We do not rely exclusively on components from a single manufacturer, but combine the most effective components from different producers to create an optimal end product.

This may sound unusual at first, but it enables us to adapt our turbochargers perfectly to the requirements of the various TDI engines.

Why is customization so important?

The different variants of a turbocharger produced over the years of manufacture and engine types often differ significantly in their geometry and durability, despite identical spare part numbers. As with other assemblies in and on the engine, turbochargers also undergo several improvements and modifications over the production period of the vehicle. Some of these updates have very positive effects on longevity, others are aimed more at fuel efficiency, response behavior or exhaust values. By taking these differences into account and adapting our turbochargers accordingly, we ensure that the end product is optimally matched to the longevity and reliability of the respective engine.

What does that mean in concrete terms?

1. The best possible bearing geometry: Our turbochargers use the most stable bearing designs available for the respective engine type. Larger thrust bearing washers and main bearings increase wear resistance and improve bearing support.
2. Targeted selection of components: Depending on the engine and application requirements, components such as the compressor housing, turbine shaft, compressor wheel, oil supply or pressure cans are customized.
3. Experience-based design: Through years of experience and extensive know-how, we combine assemblies from different manufacturers to create an improved end product.
4. Durability through quality: The high material and manufacturing quality ensures that our turbochargers offer a long service life even under demanding conditions.

Who is a new turbocharger suitable for?

A new turbocharger is particularly recommended for those who value long-term durability and the best possible reliability. Especially for vehicles such as the VW T5 2.5 TDI, which are often used as versatile everyday vehicles, it is worth investing in a high-quality turbocharger.

With our products, we not only offer an alternative, but also a well thought-out solution designed for longevity. Our turbochargers combine the best of different worlds - for maximum reliability and driving pleasure.

You can find more information about our turbochargers in our blog or directly on our Turbocharger product page in our online store.