Technology has continually improved the way that auto manufacturers seal their engines. Yesterday, gaskets constructed of cork or paper, and packed-rope rear main seals were commonplace. Today, Teflon ...

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 ...

If oil isn’t dripping from beneath your Jeep TJ’s inline-six, it’s because it’s either brand new or the rear main seal has been replaced within the last 40,000 miles. That’s just a fact of four-liter ...