Sc 400

Bandit · May 20, 2004

As our beloved SC's get older, oil leaks seem to be more prevalent. What have you guys experienced with oil leaks on the V8 engine, and how have you remedied them?

I first had a rear main seal start leaking and had that replaced for a total cost of $300.

I was also informed that I had a minor leak with the front main seal. I will wait until I replace the Timing Belts to take care of this one.

What other locations have you guys experienced leaks?

Thanks! :cheers:

sightdev · May 20, 2004

Leaks? I think the 4 liter engine is so well made that leak is not normal even with high mileage. I have 126k with no leak except for about a drop or two of PS on the garage floor every week. No need to add additional engine oil between 7k miles change interval but I do use Mobile 1. Once I did regular oil change from the quick lube place with regular oil, I had to add .5 quart before it reached 5k. Transmission is flushed every 25k but do not see any sign of leak or consumption so nothing is added between the interval. This car is like a rock and it keeps on ticking with same efficiency as it did when it had 50k on the odometer.

Looking back same experience for all the cars I had owned. None had engine oil leak of any kind and I contribute that to Mobile One. Even on the Jeeps I had owned in the past which saw its fair share of towing and off roading.

With current technology and precision going in to designing engines, the days of oil leak is not so common unless it’s a defect from factory.

Bandit · May 20, 2004

I do not think that Mobil 1 is the reason you have never experienced an oil leak. It is more than likely good luck. Mobil 1 is a slicker thinner oil at temperature, so if you experience a leak, Mobil 1 is more likely to pass through this leak more freely.

I agree that the Lexus V8 is a very high quality engine, but gaskets are very susceptible to aging and developing leaks.

The problem with oil leaks is determining their source. It's easy to see at what point the leak is hitting the floor, but its another point to determine where this leak originated from as the oil leaks, it takes the path of least resistence and could be coming from one point, but hitting the floor 1 foot to the left and 6 inches to the rear.

Its great that you have never experienced a leak, but for those of us who have, I am sourcing input from the guys that have and how they traced it and what measures they took to correct it.

Thanks for any Help!

:cheers:

Maximaboy1 · June 11, 2004

I have a 95 SC400. Leaked about 3 times during my 6 month (as of now) ownership. The reason was a loose oil filter on all 3 occasions. Hasn't leaked since I replaced the oil filter with a Pennzoil. I believe it was a poor quality oil filter that caused the loosening.