I've been following the directions on the Auto RX for high-mileage engines. Prior to using it, my oil leakage was about 1 quart every 5K. During the treatment cycle the leakage disappeared and no oil was consumed.I used Chevron Delo 10W-40 as the dino base. Now during the rinse cycle, it used about 2/3 quart in 500 miles and none was leaked. Used Valvoline high mileage 10W-40 for the rinse because of the additional detergents. With that level of use, I'd expect smoking exhaust, but it's not smoking either.

High mileage directions call for another treatment, which I plan on doing. But the oil use puzzles me...the leaks have disappeared and the exhaust is clear. PVC valve is old and needs changed, but I don't think that's it. Any ideas where the oil is going?

Taking another 500 mile trip tomorrow, we'll see what happens.

 

If I remember correctly, the oil consumption should stop around 2-3k miles after your final treatment. It was something about removing the blockages, and having them re-stick.. I dunno. The Auto-RX site has something about it.

 

I also found that Valvoline Max-Life is a synthetic blend, although it's not labeled as such. I was going to do a second treatment any way as per the instructions for a high-mileage engine and this weekend it will hit 1500 miles on the rinse cycle.