Hello gents.

i own a AJ16 XJS, that I have been using Mobil 1 High Mileage 10w40 in for a long time now. I committed to this about 8 years ago because it’s synthetic, has a good additive package and had a high 1100 ZDDP at that time. …..Great. All boxes checked… I vowed to never again worry about the topic of oil again.

Then they changed the ZDDP to 1000 in 2017…… I didn’t like it, but I decided to stick to the same thing.

Now, they have dropped it to 900

Now I am thinking I should go ahead and switch to a higher ZDDP brand oil.

The brand is irrelevant, really, but I am just concerned with the plunging ZDDP.

I know people think these topics are just referential, and they are, but the problem, at least my problem, is that whatever type and brand of oil you think you are using, it’s no longer what you think it is from 5 years ago, because manufacturers are constantly changing formulas for either cost savings or to meet a new mandate, but yet call it exactly the same thing they did before, and label it exactly the same, even though it’s not the same formulation anymore. And it seems like plummeting ZDDP is the common issue.

I honestly don’t know how important ZDDP is in a AJ16 engine, but if it is, then I should probably stick to something that has a higher content. From what I understand it is a flat tappet , so the ZDDP IS important, I THINK .

Is ZDDP content anyone here is concerned with in their AJ16 cars?

thanks

 

zddp is not the end all be all of oil, and these cars have roller cams. if you need more zddp just switch to mobil 1 0w40 it wipes the floor with the 10w40

the factory fill for these cars was absolute trash regardless

 

The AJ16 tappets are flat AFAIK

 

you’re right i had a brain fart, a damb ohc setup is basically flat tappet. regardless these aren’t 1960s cams made of grated cheese, they aren’t demanding and wiping out isn’t something to be worried about

 

No worries.

There are many ZDDP additives out there. Here's one:




Cheers
DD

 

I thought about this but I don’t like the thought of an additive. I don’t know how it will work with whatever additives the oil already has.

I do wish companies would not keep “reformulating”. I had already settled on the Mobil 1 High Mileage 10w40 and had no reason to change. I do know these cars run on virtually anything, but the lowering of the ZDDP is really what is concerning me the most.