Catalytic Convertor contamination using Rotella?

[JonT718]

Ok,

Wanted an opinion from the folks who use Rotella on non TD cars.


I've had the Rotella 5W40 in my 2001 Jetta 1.8T for about 5k miles now. I know from the get go that this is a non 502.0 approved oil but a lot of the VWVortex forum members love this oil (not just the diesel guys) so I decided to give it a try.

The oil is great, I get pretty good gas mileage (26-28 mpg with 30% city/70% highway). I switched over to Rotella last November during the cold NE weather. It’s great, no noisy starts and it doesn’t consume as much oil as M1 0W40.
Overall, really like this oil. See my UOA:

Details on the condition/maintenance of the car: http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1674286&page=2


However, to the point. Some folks eluded to the fact that the ZDDP additives can or could poison your cat. I am not sure if there is any validity to this. However, yesterday I ran a VAG diagnostic and I pulled a P0420 code (Catalyst System Efficiency Below Threshold (Bank 1)) I am not sure if this is correlated to me using the Rotella oil but I am in the process of investigating this. It could be my o2 sensors or could be the result of the oil blowing past my turbo and contaminating the cat. Will post updates …

 

[440Magnum]

Catalyst poisoning from ZDDP (or any other catalyst contaminant such as lead or manganese) is a total-dose kind of thing. It depends on how much oil your car burns, and how much contaminant is in each ounce of oil burned. Rotella has approximately twice the ZDDP per ounce of oil as the latest low-phosphorous formulations. Actually, its not even that much more- the new oils run ~600-800 PPM, RTS has about 1100 PPM, or between 30 and 40% more. But let's go with twice as much for simplicity.

Think of it this way- if you burn X quarts per 10,000 miles of the latest low-ZDDP formulation (M1, PP, whatever), it will poison the catalyst at about the same rate as if you burned X/2 quarts per 10,000 miles of Rotella. Or to turn it around, Rotella will damage the cat the same amount in 5000 miles that the other oil will in 10,000 miles.

So- reduce your oil consumption (a PCV trap is a good start if you don't have one, plus fix any turbo seal problems, etc.) and use the better oil... or use the better oil and just be prepared to replace your catcon a little sooner. No big deal either way, IMO. Use the good stuff if you like your car and want to keep it a long time.

 

[pbm]

If your car burns a lot of oil (which most VW 2.0's do) I would not use an oil with high ZDDP levels.
I wouldn't have a problem using it in a car that used no oil.

 

[dgee]

seems like your car uses oil.
and the oil is getting into your cat

 

[IndyIan]

I'm pretty sure I had Rotella T 15W40 in my Neon at an autocross on a banked oval last summer, sustained high rpms and G forces had the car pulling a fair amount of oil through the pcv system from oil building up in the head. It produced enough blue smoke that people thought I had major engine problems(it is a neon after all).
Anyways my etest this spring had no issues at all, but I guess that was at most half a quart of oil over a day of running and my car goes through a quart every 4-5000 miles or so.
Maybe its just a lazy O2 sensor for your car?

 

[JHZR2]

Originally Posted By: pbm
If your car burns a lot of oil (which most VW 2.0's do) I would not use an oil with high ZDDP levels.
I wouldn't have a problem using it in a car that used no oil.


+1

It is a ppm-hours issue, and ZDDP levels that are high will bring you to a deactivation point quicker than lower levels.

If the 2.0 doesnt have a flat tappet cam, I would not worry about zinc. It is an obsolete technology, which has a required place only really in the world of flat tappet cams, IMO.

 

[Steve S]

I would gamble with the 02 behind the cat.

 

[Hemi426]

I wouldn't own that piece of **** engine (VW 2.0). It is a notorious oil burner and all but the lowest zinc motor oil will poison the cat.

 

[pavelow]

Well, I have a 04 Jetta with a 2.0 and it only burns, at most, a half quart in 5000 miles. Worst oil consumption was a quart, but that was on a 1800 mile road trip with the engine running over 4000rpms (85mph+ cruising speeds) for the majority of the trip, so that's to be expected. I have run Shell Rotella syn 5W40 since I did the first oil change at 3000 miles. It now has 55000 on it and as far as I can tell, has suffered no ill-effects from the HDEO.

Either I got a good 2.0 or the use of the Rotella syn from OCI #1 has helped keep my engine from becoming a oil burner. lol

 

[BobFout]

RTS is SM, it's just not ILSAC rated.