“How To”: Gen 3 LS Motor Oil Cooler/Backing Plate Gasket Replacement

Let's just be honest for a moment... Gen 3 LS motors are going to leak oil. It's just a fact. Now that we can admit that, we can also fix the problem.

Most oil leaks on the Gen 3 LS's come from one fo four places:
1. The valve covers, specifically the driver side.
2. The oil pressure sensor due to the o-ring going bad.
3. The Rear Main Seal (have fun removing the transmission, or shelling out the money to pay for the shop labor).
4. The Oil Cooler/Backing Plate gasket.

This video covers the last of these. It's actually a thankfully simple job that truly only requires 1 tool, a 10mm wrench, but raising the front end with either ramps or a jack and strands makes it much easier due to more space to work. A torque wrench rated in lb-in is recommended, but not exactly required provided you are careful with reinstalling the 2 bolts.

There is one major difference you need to look at though between the oil cooler - equipped models and those with a backing plate. Those with an oil cooler use a gasket that has two circles in the middle divided by gasket material while those with a backing plate have a single opening in the middle of the gasket. Be sure to get the correct one for your application.

When reinstalling, do not use any type of sealant on the gasket, and be sure to torque the bolts to 87 lb-in (7.25 lb-ft).

Either gasket can be purchased at your local auto parts store, or on Rockauto.com.