3.0L Duramax Diesel (Problems worth knowing about)

Credit: General Motors

Common 3.0L Duramax Diesel Problems all owners should be aware of.

For gearheads the release of the 6.6L Duramax Diesel shadowed out all other events that happened in the summer of 2000. Maybe even Bill Gates leaving his position as CEO at Microsoft. Except for a few teething problems that most engines have during their initial release the engine has been providing drivers with great fuel mileage, low noise, and great reliability. With the release of the latest concoction of an engine- if we can say that- the 3.0L Duramax engine that history may be dampened.

The 3.0L Duramax Diesel brings changes that General Motors fans are still shaking their heads about. The 3.0 L Duramax Diesel engine sheds its V-style engine configuration for an inline six cylinder design. With under hood space disappearing on an annual basis engineers had to come up with an idea on how to make the engine shorter. Voila, rubber belt driven oil pump. The variable displacement oil pump that is generally driven by a chain on the front of the engine has changed locations. By placing the pump at the rear of the engine they were able to save the space needed and save the day. Or—did they.

The main concern of this system is the rubber belt. Most people have owned vehicles that have a rubber belt driven accessory drive system, you know the one that drives the alternator, power steering pump as well as other components. This belt can become dried out and crack with age possibly braking. Now if this happens to your accessory drive belt you end up on the side of the road calling a tow truck, with no worries of a damaged engine. If the oil pump drive belt breaks you may end up causing significant internal engine damage.

Credit: Chevrolet

To combat this possible problem engineers have come up with a few unique solutions. First the belt is partially bathed in oil, meaning the lower section of the belt runs in oil. This provides lubrication, and cooling for the belt while also ensuring that the belt does not dry out. Second, they have added a message system that illuminates immediately if engine oil pressure is lost to ensure the customer can get to a safe place as soon as possible and get the engine shut down.

The largest concern for future owners of the 3.0L Duramax engine should be the scheduled maintenance of the belt. Just like a timing belt, the oil pump belt needs to be replaced at a recommended interval, at 150,000-miles for this item. You will need to be able to remove and support the transmission before you can access the belt, so this may not be an item Do it Yourselfers will be able to complete in their driveways. The hiring of a professional technician will most likely be needed for this job.

Let’s all remember this is not the first time we have used rubber for critical engine related tasks. Since Pontiac began using rubber timing belts in the 1960’s the use of these critical timing components has increased dramatically throughout the industry. It has become a very common sight in automotive bays to see these components being replaced at their service interval of between 60 -100,000 miles. Timing belts are generally dry run, meaning that they are not bathed in oil. This is the largest difference of these belts compared to the one in the 3.0L Duramax Diesel and probably its saving grace.

Even though engineers have disassembled and inspected engines with mileages that range up to 170,000 miles this design still makes some in the industry nervous. Enough time hasn’t passed with the vehicles out in the wild to know if this is going to be an ongoing issue or not, maybe General Motors can appease buyers’ hesitations on this design by providing them by extending the engine warranty to cover any possible issues that may arise.

General Motors announced that it was stopping the production of the 3.0L Duramax Diesel on August.30th/2021. They cite supply chain issues is what halted production, but we can only wonder if the 3.0L Duramax is experiencing some growing pains similar to those experienced by owners of the dreaded 3.0L Eco Diesel engine. We can only hope that General Motors does not experience those issues and we will get back this great engine