blitz928

With all the talk of insufficient Zddp in modern motor oils,(specifically the new Mobil 1) has anyone gone this route and just added a bottle of this with an oil change? With Mobil 1 being cheap at Wal-Mart it seems like a bottle of this at around $7 might be the ticket.


http://www.zddppluscentral.com/

Jfrahm

I use a bottle of STP. I suspect the new oil additives replacing ZDDP are sufficient, but for a couple bucks I figure the STP will do no harm.

blown 87

BG MOA

dprantl

Mobil-1 15W-50 still has high levels of ZDDP.

Dan
'91 928GT S/C 475hp/460lb.ft

jcorenman

^^^ what he said. It is confusing because different weights of Mobil-1 (and most oils I suspect) have different additive packages.

Here's the latest Mobil-1 product guide:
http://www.mobil.com/USA-English/Mot...duct_Guide.pdf

The 15w-50 flavor is SM-rated (not GF-4) and has 1200/1300 ppm of phosphorus/zinc which is fine. (The SM rating only limits zinc/phosphorus for weights in the 0-30 range).

My preference is to find an oil with "proper" levels of ZDDP rather than using an additive. Proper oil formulation is more than just one component, and I am not convinced that "messing with the recipe" is the best idea.

Greg, you indicated in another thread that Mobil-1 was not your favorite. It would be interesting to hear your current thoughts.

blown 87

Still not my favorite.

I am going on what Mike Grubber told me, he is the Racing director for Valvoline, and a friend, we worked together for several years at one of the plants that made oil.

He says that right now the Mobil one is the worst synthetic oil on the market, and that came as a shock to me, because he had recommended it in the past.

It has a lot to do with WHICH additive packs are used, that is where oil companies make a choice to make a better product or save money.

I have been out of that end of it for so long I just have to trust what folks that know tell me.

I no longer use M1, or any SM oils in a flat tappet engine.

You can get Valvoline racing oil with the proper amounts of zinc at most major races, that is what I do when I can.

Unless they have changed the law, you can not buy the good stuff at parts houses any more in the US.
I have no idea about the diesel oil being used in gas engines.

I am all ready seeing some pitting on cams that I think is due to not enough zinc.

Toms928

Mobil 1 is a competitor, you don't think he may a little biased since he works for Valvoline. Just a thought.

blown 87

I am sure he is to other folks, but remember he had recommend it to me for a long time, in fact this last time is the first time in 20 years he has recommended Valvoline to me.

So to answer your question of if Mike may have been lying to me, not a chance.
Now if you meet him at a race and had not been a friend of his for 30 years and asked him a oil question, you might get a different answer than I would.

We used to get 12 gallons a month of Valvoline, all the car guys at the plant would buy Castrol for our cars.

We both share a common hatred of Ashland Oil, and it is one that runs deep.

I do understand why you would think that though.

The other Greg

FredR

My favorite oil that I could get over here [up in Dubai] was Redline 20w50 and it worked just fine in my 1990 S4. After my crash 4+ years ago it was a couple of years before I re-entered the 928 ring with a 1992 GTS powered by my S4 motor [original motor with PO suffered TBF].

At that point in time I could not get the Redline so the local agents checked with Porsche and promptly filled my motor with Mobil 10W40- the only grade of Mobil 1 available here. My engine has always used oil but the rate of consumption was way too excessive in my opinion- about 1 litre for every two tanks of fuel [say 900 km or 500 miles]. By book definition that is acceptable [just] but not to me.

I did manage to get 3 quarts of the Redline at one stage and went back to it but noticed the motor ran a bit hotter in summer thus demonstrating the oil does play a significant part in the cooling of the motor. Thus I reckoned with 20w50 I need more oil cooling. With the Mobil in the engine I took it very steady during the hot season.

I now run Castrol GTX dino oil [good ZDDP] and it seems to work fine but I am worried that some damage may have been done by the Mobil 1. Given our hot climate I am puzzled as to why Porsche use 0w40 in their new motors. For sure Cayenne turbos go through quite a bit of oil but no damage has ever been reported.

I am just hoping no damage has been done to my motor having heard the stories about damage caused by ZDDP deficiency- why flat tappets should be particularly vulnerable to this damage is still a mystery to me.

The motor still uses some oil with the GTX but find it is acceptable at around 1000 miles per litre when pushed a bit harder. I will just change the dino oil more frequently [about 3000 miles].

Regards

Fred

GregBBRD

Torco makes an oil additive with ZDDP in it and we've used it with very good results on the people's cars that still want to run their "old" favorite oil.

Fred: I'm surprised that Castrol GTX still has the proper additives there. That doesn't seem to be the case, here. You really need that 20-50, in your climate. Porsche's newer engines are designed for thinner oil. Flat tappet cams have no oil pressure that separates the cam and the lifters...they are splash fed. The additives act as a the "cushion" between the cam and the lifters, as the cam "scrapes" over the lifter.

WallyP

The nose of the cam sees the highest loads of any engine part...

FredR

Greg,

I suspect you chaps over the states have tougher pollution regs that may figure in this. castrol have a local blending plant in Jebel Ali [just outside Dubai] and I believe they formulate to traditional Euro specs. It might be wise to check with the plant that they still maintain this spec especially as this was why I selected it in the first place.

I wondered if there was a sexier reason why the concern on the lifters but understand why that would be the case on a splash based system which runs in a strong oil mist anyway. I guess once the case hardening on either the cams or lifters goes it will chew away mercillessly on whatever surface went first.

Regards

Fred

GeorgeM

Brad Penn

andy-gts

Don't shoot me but .....I have been looking at amsoil racing and seems to have high zddp, good detergents and compares well with other oils. I may try some as we have 6 cars (kids and all) and it may help control costs also.
I will dig around for the data. Seems on the surface to be a good deal for the individual.

Marine Blue

I've been using Amsoil and will continue to do so. It's not the cheapest source for oil but if you don't drive frequently and if you can share the shipping and 6 month membership cost with one or two people its really not bad