ACL High Performance Standard Size Main Bearing Set, #5 Thrust Bearing Position Subaru WRX 2002-2014 / STI 2004-2021 | 5M8309H-STD

ACL's main bearings are crafted from a softer metal. This design safeguards your crank and engine block from excessive wear. A thin oil layer lubricates the bearings and crank connection, enabling the crank to 'float' and minimize wear. Proper support from these bearings is vital to prevent oscillations and wear that can harm the crankshaft and other parts as the engine goes out of balance. Bearings with extra oil clearance can handle the stress of high - horsepower motors better, but they'll experience more wear during startup. These are recommended for experienced professionals only. Remember, Subaru main bearings are specific to either a #5 or #3 journal bearing position. You need to know this before buying as engine internals aren't eligible for exchange or return.

To use these ACL main bearings, first, make sure you know if you need the #5 or #3 journal bearing position. Once you've installed them, the thin oil layer will start lubricating the connection between the bearings and the crank. This helps the crank 'float' and reduces wear. Be aware that if you've chosen bearings with extra oil clearance, they're great for high - horsepower motors, but you'll notice more wear during startup. When it comes to maintenance, regularly check the oil level as the lubrication is key to the bearings' performance. Since these are engine internals, if you're not an experienced professional, it's best to seek expert help for installation and maintenance. And remember, you can't exchange or return these parts, so double - check what you need before buying.