I have a 96toyota Camry the rear seal is leaking oil.4cyl 2.2 engine I talked to a mechanic he told me to use Lucus stop leak oil treatment. Is it ok to use this product to seal the oil leak

Sure its okay to try it or run a thicker oil like they did years ago and still do now in work or farm trucks. No one can tell you whether it will or will not work, but you know putting in a new seal will work.

Different mechanics will tell you different things. Stop leaks are made to form, 'deposit' themselves in small holes cracks etc, the bad thing is that there are places in your engine where they end up forming in tern possibly preventing optimal oil flow. Personally I have used a stop leak for my 99 Camry v6 head gasket seals, but I use MUCH less than recommended on the bottle. I have found that it worked quite well. I use to be able to smell the oil dropping onto the manifold and burning, I haven't had that in 10,000+ miles. You should try using a high mileage oil to rejuvenate the seals. However you may avoid full syn, i have heard problems when people switch to full synthetic because it cleans so effectively it will remove the small deposits in the tiny cracks or holes that have formed in the seal which have worked in your favor of slowing down the leak. But you said you have a 4 cylinder, they are fairly easy to replace if you have some tools, a helper, and some mechanical know how. If not it may be better to get an estimate and get the repair instead of spending 50 bucks on stop leaks and oils. From what Ive heard inline 4's are quite inexpensive to have fixed. $100 or so?

Also keep in mind stop leak products are only meant as best to be temporary. Its only a matter of time before you'll have to replace the gasket.

Replace it a lota pressure make sure PVC system is breathing