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Lucas Oil Stop Leak

First time poster and dumb question about Lucas Oil Stop Leak. The directions say use 1 quart of LOSL for 4 quarts of oil. If I am changing my oil and the capacity is 4 quarts does that mean I put in 4 quarts of oil AND the LOSL or does the LOSL count towards the oil capacity?

How about starting from the top . . . ?!

Exactly what leak are you trying to fix . . . ?!

I’d put in 4 quarts of oil, and a 1/2 quart of the stop-leak.

Then when the oil level drops a 1/2 quart, add the other half of the stop-leak.


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Honestly I do not know. I replaced the valve cover gasket last year and it stopped leaking until the last month or so but now there is a drip from somewhere. The car is a 2002 Maxima that is just used to get to work that is only about 2 miles away. Thanks.

What vehicle is this and what is the oil capacity ? Seems simple enough , put in 3 quarts - add Lucas stuff - check oil level - add oil to bring to full mark .

At least that is how I did that on an old truck we had.

Edit: Forgot to mention that I did check the oil level before driving the truck for several weeks before returning to my weekly schedule .

I would suggest you find out what is leaking first

stop leak products won’t fix all leaks

It definitely won’t fix a gasket that is split wide open or an oil filler cap that was left off or an engine oil drain plug that’s loose, to name a few examples

I second the question of Mr @db4690… What area are we trying to stop leaking here? Stop leak in bottles is not the way to go about, well, stopping leaks. If it works…it will only work one time and when it starts leaking again, (as it surely will at some point), it will be the last time any fix in a bottle will solve that issue again, IF it ever slows or stops the leaking to begin with. The bottle also exposes every other seal that is not leaking to the same chemical (that is designed to re-emulsify and or swell the rubber seal to stop leaking)…so the bottle will not work a second time on those gaskets that haven’t even had a change to leak the first time yet… Yeah… me no likey the bottle idea, never have, but…

I need to understand that not everyone enjoys taking things apart and getting dirty like I do, so I try to be sympathetic. If its an easy seal to stop leaking…just replace the offending seal, but alas, that prior sentence of mine again.


So you count the stop leak as part of amount of oil you add? I was not sure if it was in addition to? Thanks

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I agree that fixing it is the best and proper way to stop the leak, but this car has been turning into a money pit lately and I am tired of messing with it. So I figured that I would try the LOSL. Thanks.

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Yes the additive whichever one you using… becomes part of the oil capacity.

4 quart capacity would be… 3qts oil…and 1qt of the additive… coming to 4 total

What leak are you trying to stop here? Valve cover? Front main? Rear main?

Thank you all. Maybe when it gets warmer I will look at it more.

Sounds good… Yeah if I had to choose, I would prefer to let an engine leak in its natural manner as opposed to not leak in an unnatural manner.


If you’ve already replaced both valve cover gaskets, check the spark plug wells, another frequent source of leaks on a car this age. Another source may be the external line from the transmission to the transmission cooler inside the radiator, cheap and easy fix…

The good thing is that these engines are practically bullet proof BUT the above valve cover leaks dripped directly onto the alternator causing that to crap out.
By 225,000 miles, besides the things mentioned above one channel of the radio had quit, starting to get rust though,at a rear wheel well and when the AC quit, decided to put it to bed.
But it was a great car.