Rotella Syn 5W40 with VW Jetta 1.8T: Clogged cat ?

[JonT718]

I recently added Rotella Syn 5W40 to my 2001 Jetta 1.8T . I have read that due to some additive/detergent in the Rotella that I risk clogging my cat.

Now has there been any documented evidence/proof that this has happened to anyone? I'm loving the price/reviews on Rotella but am concerned with this issue.

My Jetta presently has 128k miles and has been running syn oil since 100K.

 

[Gunatics_Adler]

There is a possibility that Zinc can poison the catalytic converter in cars. It really depends on the engine and the shape its in. Being that the new stuff is CJ4 and SM rated, I think it would be fine and many people use it in their cars here. But the ad pack is excellent in that oil, and I would rather protect my expensive engine over my catalytic converter.

 

[JohnBrowning]

No their is no evidence that useing any oil that has ZDDP which is all morotor oils right now will cause harm to Cat. SInce all oil has ZDDP the main difference is that SM oil have about 750-800ppm of ZDDP and Diesel oils have about 1200-1500ppm in them. Also any SM rated oil that is latter CJ ratted can also raise it's ZDDP amounts.

GM mostly said Hey automotive world we are spending too much money warranty replacement of catalytic converters especialy in California and those states that have the same laws. We need to lower the amount of zink, phosphorous and the volatility of the oil so we can save some coin on cat's. Now keep in mind GM engines easily over all burn more oil then any other OEM's engines hence the reason they have higher cat failure rates. Well the other OEM's thought it sounded good too at the time since none like spending money on warranty items if it can be helped. SO they jumped on board and bam a new class of oil was born.

It is easier to take the ZDDP and Sulfur out then it is to redesign their engines to burn less oil. Since the cat is not in the oil circuit the only way any additives like ZDDP can get to it or them is to be combusted and passed out the exhaust.


I have ran oils like the old versions of M1 from 15W50 to 10W30 and they used to have really high ZDDP around the 1200-1800ppm depending on which M1 product you where looking at. Not once has anyone in my family ever had a pluged up catalytic converter.I also run oils like Redline,Motul,Penrite and Amsoil and Amsoil used to have a lot of zink in all of their products. Again no problem with cat issue's. My 2003 Camry has been on a diet of fortified oils with about double the additive levels of current oil since I bought it with 4 miles on the odometer and I would think that almost 7 years of feeding it wither oils heavily additized or oils that I added additives too to increase them would have taken it's toll by now since 7 years is a significant period of time when considering all the oils and additives that have been in my engine!

By the way my Camry has been ran on RTS 5W40 at least 3-4 times. Also look at all of Redlines customers I dare say that if they where clogging up cats left and right we would be hearing about it!

 

[Gary Allan]

Quote:
No their is no evidence that useing any oil that has ZDDP which is all morotor oils right now will cause harm to Cat.


Sure there is. Multiple studies (which I don't have the links for). It's just lacking in significance over some time span. SH and SJ ..SL

Plenty of cats lived beyond their host chassis useful life. 2001 we were in SL, iirc. Plenty of phosphorus to poison your cats. I don't see a run on platinum due to all the cat failures.

I would probably be more concerned that the newer models tightened the cat efficiency thresholds (making formerly NORMAL cat condition unsuitable), but that would be beyond the 2001 model year.

I've yet to be spanked on my belief that it's the amount of zddp that you present to the engine. Total pounds of the stuff. Some of it's going to volatilize out of each oil change. If you're doing 3k/3m with SM and another guy is doing 5k/6m with SL ..you're processing the same or more zddp through the engine per mile.

 

[JonT718]

Just wanted to report back that I've put about 1300 miles running Rotella and have since added an additional quart of oil to top off the 1qt that I burn. (total of 5 + 1 qts oil used)


I checked the level this morning and noticed that it's back down to the low level on my dipstick. Meaning almost 3/4 of the oil is gone after about 300 miles.

Either the engine is just eating up this oil or I may have some other problem. I'll be submitting a OA to Blackstone to see what may be going on.

 

[KW]

That's pretty heavy oil usage.

 

[Gary Allan]

If it's accelerated consumption, don't worry. The oil is more than up to any task you are going to ask of it. The consumption will retreat in the. Make sure your PVC system is functional.

 

[HyperJinx]

I have never had to replace a cat on any car I have ever owned. They have only recently lowered the levels of ZDDp in oil so where are all the poisoned cats of yesteryear? I have put seveal hundred thousand miles on cats from cars running all manner of oil that was loaded with zddp. Rotella now has what level of zddp? 1000ppm perhaps? Is that any more than the levels of early "SA thru SL" rated oils? I am no expert so I am just asking?

 

[JohnBrowning]

Sorry. I was not clear. What Imeant was that no studies indicate that ZDDP that stays in the crank case is harmful. It is always dependent on oil consumption since ZDDP is in solutionin the oil and does not evaperate or the like. One must first burn the oil in the compustion champer in execive amounts to release the Z and the P in ZDDP so that it can be expelled out the exhaust port and into the cat. If you keep the Z and P in the oil and do not burn it then it can notmigrate out of the oil and end up in the cat.! At the rate GM engines especialy their V8 consume oil I doubt any limit on the ZDDP will do much. A componation of better piston designs and closer clearances and tighter tolerances on the GM engines would do more to extend the life of their cats.!

I read lubrizol paper that was co authoured with GM and it wassome of the worst junk science I had scence. They designed the study to produce the result they wanted. Having done more then one research study I know how to set one up to get the result I want versus doing a good study with little bias!

 

[JT1]

Originally Posted By: JohnBrowning


I read lubrizol paper that was co authoured with GM and it wassome of the worst junk science I had scence. They designed the study to produce the result they wanted. Having done more then one research study I know how to set one up to get the result I want versus doing a good study with little bias!


It's sickening how many "studies" are set up this way.

 

[Familyguy]

Originally Posted By: JonT718
Just wanted to report back that I've put about 1300 miles running Rotella and have since added an additional quart of oil to top off the 1qt that I burn. (total of 5 + 1 qts oil used)


I checked the level this morning and noticed that it's back down to the low level on my dipstick. Meaning almost 3/4 of the oil is gone after about 300 miles.

Either the engine is just eating up this oil or I may have some other problem. I'll be submitting a OA to Blackstone to see what may be going on.


Have you checked for leaks? That's not particularly high mileage for that engine, though I have seen a few K03 turbos on the 1.8T start to lose oil when their internal seals failed and send it out the exhaust.

 

[JonT718]

Hey guys I just took a sample and will be sending it in to Blackstone for analysis.


John: You mentioned that the Z & P would have to burned in the commbustion chamber for it to be expelled into the cat. Given the fact that my Jetta seems to already burn oil - could this already be happening now? (though I don't see any plumes of smoke in my exhaust)




Of note, I have noticed a slight decrease in my MPG's. I used to average about 27/mpg and now i'm getting about 25/mpg. Could this be a sign of either my cat starting to get clogged?

 

[Gary Allan]

Got a vacuum gauge? The vacuum should be about the same with no load on it until the exhaust starts adding its own load. If your vacuum drops off as the rpm increase, you probably have an exhaust condition. If you've just gone to a higher visc and drive shorter type trips, then you may be suffering minor effects of pumping thicker glue.

 

[Gary Allan]

Originally Posted By: JT1
Originally Posted By: JohnBrowning


I read lubrizol paper that was co authoured with GM and it wassome of the worst junk science I had scence. They designed the study to produce the result they wanted. Having done more then one research study I know how to set one up to get the result I want versus doing a good study with little bias!


It's sickening how many "studies" are set up this way.



Most studies are this way. There are few that aren't out to prove something ..that is, just to find out what occurs. The sponsored studies that don't serve some agenda never get published.

My best example is the GM sponsored study, written by GM fluid engineers, showing that multivehicle fluids didn't perform as well as Dex VI.

What the heck else would be the conclusion of the study? It would either prove that or it would have never seen the light of day.

Now if the study had also shown that the use of mult-vehicle formulas produced no problems other than potential issues with the highly coveted "velvety smooth shifts" that consumers DEMANDED (protesters ..with picket signs and tar and feathers outside of corporate offices-chanting "HECK NO -WE WON'T GO - TIL WE GET THE SMOOTH POWER FLOW- HECK NO -WE WON'T GO...) AND proving the significance or lack there of ..then it would have been more credible.

That's not to say that anything in the study was false. Not at all. It's what it didn't say that's important to me.

 

[Philth]

If you're using that much oil in 300 miles, chances are you have a mechanical failure somewhere. First, I would pull the plugs and check for oil contamination, which would rule out valve seals leaking and/or piston rings causing blow by. Rent a compression tester from Autozone for free and check the compression of the motor. In general, all cylinders should be within 5 psi of each other.

Lastly, you may want to look into the turbo causing oil consumption. A quick check you can do is to try to pull and push the turbo shaft. If there is ANY play when pulling or pushing, the turbo is bad and most likely the seals are shot.

 

[goixiz]

Check your outlet of your turbo cold side - if wet
then a catch can or an AOS will help. Also check your PCV valve