What's the cost for a 2012 GMC Terrain rear main seal replacement?

The cost to replace the 2012 GMC Terrain rear main seal is between $8 and $36. The rear main seal allows the crankshaft to exit Your engine case so it can bolt to Your flywheel or flex plate and transfer its energy into Your transmission. The rear main seal also holds the engine oil back and keeps it inside Your engine where it can keep Your main bearings lubricated.The rear main seal keeps oil sealed inside the rear of the engine, where the crankshaft connects with the transmission. It can be expensive to repair, often $600 or more, because it typically involves removing the transmission and, in some cases, all or part of the engine.