NO LEAK 20401 Engine Oil Stop Leak, 16 Fl oz.

Used this to stop some head gasket/valve cover leaks until i either repair or sell my car with 160K miles on. I would have to add a quart every 1000mi or so, and at stop lights you could smell oil burning. I added this with the last oil change, and after 200 miles, it seems to have stopped the leak. No burning oil smell anymore and oil level is still tip top. I don't expect it to last forever, but so far it works as advertised. Recommended if you've got an older car you don't want to sink $2-3K into to stop an oil leak.

Not sure if it works, I have 352K mileage on my 5.7L Toyota Tundra that has oil seepage

Update: As I said earlier, the leak stopped. My clutch master cylinder began leaking and replacing that plastic part involves taking half the truck apart! My mechanic replaced the main seal. He said that the old seal had swelled about double in size and was bulged way out. I poured this bottle in and drove for 2000 miles. Perhaps a person should only drive 500 miles before replacing the oil to help avoid over swelling. ...........................It is good at making a seal swell. Perhaps a bit too good?I used this on my F150 after learning that main seal leaks are common on my 4.9 liter straight six. It has worked so far. No more stains on my driveway. I hope that it continues to work.

I have an old second car that had an oil leak. I did not want to spend a substantial amount of money to replace the seals. I had already tried two other brands of leak sealer with no success. I almost gave up, but decided to try this 20401 treatment as a last resort.Finally I found a product that worked amazingly well. It completely stopped the oil leak. I do not know how long it will last. I am even ordering more of this product now, in case it is needed in the future. Hope it works for you.

stopped oil leak min my 2007 Cadillac DTS which happen to be notorious for leaking after 80k saved me about 6,000 in repairs unbelievable.

This stuff did not fix my leak. I still lose about 1-2 quarts a month from some sort of mystery leak. Didn't work for me. Nothing more to say.

My F150 has 180k miles and was starting to use a noticeable amount of oil between changes. With nothing to lose I read up on stop leak products and chose No Leak. It took a good 250 miles before it started working and by 300 miles the leaks had stopped. I've since changed oil and so far, still no leaks. I don't expect it to work forever but I'll update if anything changes.

Still leaks