1980 FJ40 2F- ZDDP ppm question

[aiel]

Hi all- Just purchased my 1980 FJ40 two weeks ago from a guy who has put on less than 100 miles a year over the past 8 years and has not changed any of the fluids in that time except to top them off. Obviously, changing the oil is one of the first things I want to do. When researching I found a ton of info here and at other sites. Living in the NE I think I have settled on Rotella 15w-40 however the T4 seems to have only 969 ppm of zinc as of the 2018 PQIA test (PETROLEUM QUALITY INSTITUTE OF AMERICA TEST PROGRAM). So I assume most people add a zinc/phosphate additive like ZDDP Plus to bring up that ppm level. However I can't seem to find what the proper zinc ppm level actually is. I have seen ppl say anything from 1200-2400 ppm. I know adding too much can cause just as much problems as not having enough. Can someone fill me in on what the correct level to shoot for is and how you do it with your oil changes?

Thanks!

 

[White Stripe]

I read that around 1800 is around where your getting close to too much zddp.

 

[coonassjohn]

Why not use the oil called for in the specs? Works well for the rest of the world.

 

[snaggletto]

I can't imagine owners from the past 28 years have been so concerned or knowledgeable about it as you. In other words, the damage has already been done. There are some specialty oils that you can obtain, Valvoline VR1 racing, Brad Penn etc..., but they are pricey. I'm not so sure the additives are actually any benefit either. Good luck.

 

[oregon fj]

In the air-cooled Porsche world (where a rebuild of a 911 motor can cost $15-20k), the consensus is 1200-1400 ppm is about right.

Rather than guess how much additive to add, I'd just buy an oil which is already so fortified. I use VR-1 in both the 40 and my 911.

 

[aiel]

Great advice. Thank you all for the help!

 

[DSRTRDR]

overthinking hurts the brain - 40 engines are closely related to a tractor

 

[David70FJ40]

I use Lucas Hot Rod and Classic motor oil. Zinc content is 2100 ppm.

 

[iptman]

The Lucas Magnum oil is ~1500 ppm zddp and available at Napa at around $20 per gallon.

https://lucasoil.com/pdf/Zinc_Values_MotorcycleOil.pdf