Lucas Oil10279 Engine Oil Stop Leak - 1 Gallon

This product works well for non pressurized rubber seals that are dry but not yet broken like valve cover gaskets, vvt solenoid seals, crank seals, cam seals, etc. probably not very effective on pressurized oil seals like oil filter adapter housings. Will absolutely not work on head gaskets because those are metal not rubber so don’t be stupid. I used on a Cadillac North Star I own with many dry rubber seals and it works fantastic and quiets the engine. My car has lots of dry oil seals that I have no interest in fixing all of them and this product is very effective. I use 10 percent approx 10 percent concentration.

I was finding oil beneath my valve covers I believe it was coming from my intake manifold just behind the manifolds. I didn't have the money all the time to change them. I added about a quart and a half and my leaks seem to stop. When you change your oil you have to add it again because you're dumping out the old stuff when you change it. It works pretty good I would recommend it if you can't change those gaskets. If the leaks are too severe nothing will work but changing the gasket so mild leaks this works

This stopped my oil leaks for about 2 oil changes. There is no magical solution for replacing leaking gaskets, but this did help.

Any thing Lacus is good

To have plenty when I need it. I know it will work and help my vehicles.

Got a leak? Put it in.Got a tick? Put it in.Got a questionable engine? Put it in.Cars, trucks, semi's , tractors, lawn mowers etc...This stuff has dramatically slowed down my leaks and engine noises. Also helps a lot on cold starts.

Didn’t see any improvement

We bought this for my wife's aging Kia (21 years old, 190K miles) that was exhibiting some leakage issues. Prior to changing the oil and adding this stop leak, I tightened all the bolts near the leaks (e.g. valve covers) to ensure loose bolts weren't the problem. Then I changed the oil, adding Lucas Stop Leak in the process. It's been month now and there are no leak issues apparent. Was it the Stop Leak? Was it tightened bolts? Or both? It's hard to say for sure, but we're happy now with the result. (Note that I've tried the bolt-tightening process before but still had some leaks, so I'm pretty sure the latest success is due to the addition of the Stop Leak). We'll continue to use!