I notice for years now my boss's 79 Ranchero 500 has had a burning, oil smell inside the cabin at times when one drives. The car has only 75,000 original miles, so I assume the engine is fine, as it had always been at least maintained on its fluids. Is the engine already starting to wear out? Is 100,000 too high for the cleveland 351. I was alarmed a little, cause I also now notice sometimes when I drive, I can see some smoke rising on either side of the car, but not a lot, and most of the time I can't even see it. I popped the hood, and notice a lot of oil seepage on top of the valve cover and somewhere behind the engine, so I guess I can only assume oil is dripping on something. It does lose about a quart every 250 miles. It just leaves a small puddle under the car. Where do these engines typically leak? Is oil burning normal with the Ranchero? How many miles has anyone here on this board gotten out of a late 70s Ranchero?