My 35th Anniversary appears to be consuming about 1 quart every 2,200 miles, and I got to thinking, is this going to hurt the cats? I cant imagine that oil in the exhaust gas stream is good for the cats, but then again mabye it wont hurt them. Does anybody have any info on this?

I have noticed that there is a lot of black soot inside my exhaust tips, and Im pretty sure it has to do with the oil consumption. In contrast, my Pathfinder has zero oil consumption, and there is no soot in the tail pipe... hmm

 

I think hurting the cats is least of the worries, id be more worried about the engine!! The 300HP rev up models seems to be famous for oil comsumption, its partly due to the thin low friction piston rings they use in these engines. Lotsa blow by, some amount of oil burning is normal, somthing like 1/4 quart (8 oz) during a oil change cycle (3000miles) is considered to be very normal. But if its consuming 1qt between oil changes id find that quite excessive, unless you spend 90% of the time in high rpms.

 

Burning 1 quart of oil between 3,750 miles oil changes is considered "normal" by Nissan.

Don't worry too much about it, make sure you always have enough!

Mobil 1 is known to "evaporate" pretty quickly. I've hear the Motul 300v doesn't do that.

 

The black soot is pretty common. I've had it since day one and haven't burned a drop of oil.

 

HAHA, Nissan also thinks the transmission are "normal" to grind into 3rd & 4th, i still dont see anything "normal" about burning 32oz of oil. None of my Nissans burn oil, not even my 90' 300ZX Turbo and all my cars are run really hard everyday.

 

Study the NOACK report for your brand of oil to see what is normal evaporation thru PCV system, then add what gets up thru rings.

 

do you have a link to this info?

 

Answer to ur question is yes----If ur Cats load up more than they have the ability to burn up they will over time get trashed and restricted. Which ---Now that I think of it may very well cause exsessive back pressure which in turn may cause more blow by resulting in more oil loss.

 

Study which metal additives poison the substraight in cats and analyse the oil you use....zinc...Common catalyst poisons are lead, sulfur, zinc, manganese, silicone and phosphorus.

ZDDP has been reduced in many newer oils in case they are consummed.

 

For the blow buy you should get an oil catch can.