4 Of The Most Powerful Diesel Engines Ever Built By Volkswagen

Volkswagen and its subsidiaries make a wide variety of powerful and reliable engines that can satisfy just about any driver, whether it's having some fun in a Golf R, or commuting to work and back in a Tiguan. However, for car enthusiasts, some of the most powerful car engines in the world are Volkswagen engines. The company also makes a significant amount of diesel engines, as they are popular in European cars where Volkswagen is based and does a significant amount of its business.

Volkswagen has over 10 subsidiaries that produce cars and parts that are used across its different brands, including the likes of Audi, Porsche, Lamborghini, and more. Thus, one might see an engine from one Volkswagen subsidiary in a car from a separate part of the company. Volkswagen makes a wide variety of high-performance engines packaged into various cars from various automakers under the VW umbrella, some of which are specifically diesel powered. These are the most powerful examples of diesel-powered drivetrains in Volkswagen's lineup.

While this is listed as a 4.0-liter engine, this Volkswagen V-engine technically only offers 3.9 liters of displacement. Volkswagen first introduced the engine through its subsidiary, Audi, in May 2003. It was the second V engine from Audi to use at-the-time newer technologies of chain-driven overhead camshafts and ancillary units. This V8 TDI engine featured a maximum rated power of 275 brake horsepower and 479 lb-ft of torque. 

Volkswagen only used the engine in the Audi D3 A8 car, and only for a relatively brief time before it was replaced by its mechanically similar successor. At the time, it was the highest power and highest torque diesel V8 engine fitted in any mass produced car worldwide in 2003. Though made with several innovations that changed the mechanics of the engine, the engine that superseded the 4.0 — the 4.2 V8 — is fundamentally identical to its predecessor, and has many of the same physical characteristics and features, just refined.

The successor engine for the well-loved Audi 4.0 V8 engine, the 4.2 V8 engine — though technically a 4.1-liter engine — brings much of what car enthusiasts loved about the 4.0 V8 to the modern day, with adjustments to bring the engine up to speed for newer users. It is currently the highest power V8 diesel engine for passenger vehicles in the world. The newer version features 90 mm spacing between cylinder bore centers, and brings back the roller chain drive for the overhead camshaft and ancillaries. 

This engine has a rated power between 315–385 brake horsepower depending on the A8 model year and variant you have, along with a maximum torque output of 590 lb-ft. There were some mechanical concerns with the 4.2 V8, namely the plastic bearings present in engines for model years before 2009, which can wear out after 40,000–50,000 miles. Despite this, users and experts otherwise consider the engine to be relatively reliable when properly maintained.

One of the engines that was initially fitted in the Volkswagen Touareg (2002–2008) and Phaeton (2003–2007) models was the 4.9 V10, which featured a rated power of 308 brake horsepower, and a maximum torque output of 553 lb-ft. The Touareg — and similarly with the Phaeton — could accelerate from 0-60 miles per hour in just over 7 seconds, and got around 19 miles to the gallon. It could drive around 505 miles on a full tank, with a top speed of around 140 miles per hour in ideal conditions.

According to user reviews, the Volkswagen Touareg equipped with the V10 TDI was notorious for having major issues and requiring extensive repairs. One user on Reddit recounted a friend spending over $6,000 on repairs on an engine with just 50,000 miles on it. However, other Reddit users also recounted adoring their V10-equipped cars, and also didn't experience any major reliability issues. There was not a particular consensus on whether the engine was reliable enough for daily use, but given the mechanical complexity of the engine and the now-aging vehicles that utilize them, Touaregs and Phaetons equipped with the V10 TDI should be approached with caution.

The Volkswagen 5.9-liter V12 is the most powerful mass production diesel engine to date by the automaker, sporting a rated power of up to 500 brake horsepower and a maximum torque output of 737 lb-ft. The theoretical top speed of the Audi SUVs equipped with this engine is over 170 miles per hour, giving it plenty of room for those who enjoy sporty SUVs that are still capable of hauling passengers at more responsible speeds. 

The road-legal V12 is installed on Audi Q7 models, though a prototype version of this engine was initially used in the Audi R10 TDI race car, and served to inspire the development of this engine for bulkier SUVs. However, at a starting price of $185,000 at the time of release, it's clear this is not going to be the most affordable dollar-to-horsepower diesel to buy. Considering the base price, and that it didn't meet U.S. emissions regulations for import anyway, this is an especially rare European car that didn't exactly draw too many customers.