by DaveinOntario, October 10, 2015
Had a leaky crankshaft seal replaced on my '05 Corolla and shortly thereafter began to notice an oil consumption of about 0.5-1L per 1000 km's with no leaks visible under the car, so figure it's getting burned. Can this be related? I have a very high mileage car (765,000 km's) so some oil consumption shouldn't be a surprise, but the timing of the seal replacement had me wondering.
The replacement crackshaft seal itself shouldn't cause excessive oil consumption, unless contaminants were accidentally pushed into the engine during its installation. Possible those contaminants are causing damage to the clyinder liners, causing oil to seep by. I'd see if there is oil leaking from the new seal - might not be obvious, slow oil leaks are notoriously difficult to pinpoint.
Then again, with this sort of mileage - also not unusal for a car to suddenly consume oil. I've seen some cars that go from consuming a few oz's per oil change interval to running almost completely dry the next time.
At the rate of your oil consumption - 0.5-1L / 1000 km (~ 0.5-1 quart / 621 miles) for 765,000km (~475,000 miles) - fairly excessive, but not outside what I've seen before.
Thanks for the reply. I'll take a closer look for leaks. Also going to try several short interval oil changes with full synthetic to try to clean things up and perhaps reduce the speed of oil consumption.