Audi Engine Oil Cooler Line - Rein 078121058AM

Product Information

An engine oil cooler is a heat exchanger designed to assist in maintaining stable and adequate oil temperatures to prevent oil breakdown under heavy load conditions. It works by circulating engine oil through a series of small heat conductive passages that are exposed to either airflow (air to oil type) or coolant (water to oil type), depending on the design. Good quality synthetic oil begins to lose protection and lubrication properties generally around 300F and breaks down completely before 500F. In situations where the oil may be approaching this temperature range, it's crucial to bring it back down to standard operating levels.

In an air-to-oil cooler, good airflow is required to ensure the heat is effectively vented. In water-to-oil coolers, engine coolant flowing to the radiator is used to cool the oil. This does not require any additional ducting or fans, which makes this design increasingly popular with carmakers due to additional benefits in engine bay packaging.

Engine oil coolers typically have a thermostat built into the oil cooler circuit that opens and closes depending on the temperature of the oil, to avoid overcooling when temperatures are in a good range.

Engine oil coolers can fail for a few reasons, most commonly due to leaks, blockages, or physical damage. For air-to-oil coolers, the most common failure mode is physical damage caused by road debris or age/rust. Water-to-oil coolers have a different issue. Internal failure can cause coolant to mix with the oil, which will cause a milkshake-like consistency in the oil similar to a blown head gasket.

• External Leaks: Air-to-oil coolers are exposed to difficult road conditions and can be vulnerable to damage from rocks or other road debris.
• Age/Corrosion/Rust: Due to the harsh exposure to the elements, engine oil cooler lines are susceptible to increased levels of corrosion or rust, especially at the fittings. If bad enough, the fittings can become corroded enough to leak, or at minimum lose the ability to service the oil cooler
• Internal failure: Water-to-oil coolers are susceptible to internal failure, which can result in the engine coolant mixing with the engine oil. If gone unnoticed, this can result in engine failure, so it is important to regularly observe coolant or oil quality to ensure the oil cooler is in good shape, especially in older, higher-milage vehicles. Mixing water and oil will result in a “milkshake” style appearance in the fluid.
• Exterior seal leaks: When replacing a water-to-oil style cooler, it is critical to also replace the seals to avoid oil or coolant leaks upon reassembly. These seals can leak either oil or coolant depending on age, mileage, and heat cycling.

About Rein

Founded in 2007, CRP Automotive introduced the Rein Automotive line of OE-quality replacement parts to the aftermarket. And in just two short years, Rein Automotive has become very popular among both warehouse distributors and professional repair technicians. Rein is the German word for “pure”, and has come to be synonymous with quality in the automotive aftermarket. A true dealer alternative.

The Rein brand includes a growing number of “better than OE” parts for selected applications. These parts address known weaknesses and premature failures of factory parts. Many of these replacement and service solutions have been developed with the help of our Innovation Council, a hand-picked group of experienced professional repair technicians and shop owners throughout North America.

All Rein Automotive OE-quality parts are backed by the CRP Automotive standard, and are backed with a ISO 9001:2015 quality management system certification. Each year, CRP Automotive ships thousands of Rein Automotive brand products. And with widespread NAFTA market distribution through strategically placed warehouses in Cranbury, New Jersey and Puebla, Mexico - OE-quality products like Rein Automotive are delivered to customers both faster and more cost-effectively than ever before.

In 2017 Rein partnered with FCP Euro in competing a W204 C300 AER car for the 2017 season. The partnership focused FCP Euro to dive deep into the Rein catalog offering, and hundreds of new products were added and integrated into our catalog. Hundreds of new packages were created not only using the full part pine up of Rein products, but also the entire family of CRP products like Pentosin.

Rein is also an innovative brand, winning numerous trade awards — including multiple new product innovation awards at the annual AAPEX trade show.