The V8 Owners Forum -

hello all,

I have some millers running in oil for when I start my 4.6 engine after a substantial rebuild.

I also have some ZDDP additive.

Do I need to add the ZDDP additive to my engine break in oil, or shall I just save it for the Valvoline vr1 20w50, after I change the oil.

I know VR1 has a good zinc content, but the running in oil i cant find anything about, and im not sure if i should use it straight away.

cheers

scott

When i eventually get mine up and running im probably going to stick to the 20/50 valvoline racing from the start, im not a fan of additives and believe the oil itself is a very high quality lubricant in itself.
I think as long as you use the recommended 20/50 grade you should be ok.
May be best to speak to millers technical about additives if you do go this route.

Just to be contentious.....

After years of 'running-in' engines I now just give em hell once the cam is broken in.

As an example Tony's 4.8 was given 7000rpm on the rollers and had less than 50 miles on it.

Just been through this with my new 4.6. The important part of the running in process is running in the cam - this is where the ZDDP additive comes in as it provides the various zinc compounds to ensure the cam lobes and lifters bed in correctly. also aids bedding processes elsewhere.

Most running in oil has a level of the zinc additives in it but the ZDDP additive ensures the zinc level is high.

I used running in oil with the required level of ZDDP additive. While the engine is running the vehicle is not and my intention is to change the oil filter at 1500km but because of the ZDDP leave the oil in until about 3000km and then change the lot to normal oil at about 3000km. By then the cam will be well and truely run in with much of the engine run in. I will then change the oil and filter again at 10,000km then at normal intervals (10,000km).

So I would add the ZDDP to the running in oil at the start.

garry

cheers all,

I'm not sure if the millers has the right ZDDP levels.

So I think I just drop them an email to find out, if I had to guess....i would say it does but best to check.

I will be adding the ZDDP additive to the VR1 20w50 i have, but in some amount of miles from the running in.

I have read somewhere, that it is best to drive it after the cam is bed in, but with 4-5 power runs to 4500rpm....and very little idle.

regards

scott

Id just drive it normally without going crazy on the revs.
Just coat the cam liberally in a good quality lube product from someone like comp cams.

https://www.turnerengineering.co.uk/PBS ... UufD%5FBwE

With a new build, I'd run the oil pump with an electric drill and make sure it is getting to the rockers etc before starting the engine. Any cam lube etc will soon get washed off with the engine running and oil circulating.

I'm a bit confused about using a wear preventing additive when bedding in. Bedding in normally consists of any high spots caused by machining work being removed. And with modern machine tools, far less than once was the case. Once everything has 'polished up' is the time to use a decent anti-wear additive.

Running in oil is anything but anti wear - in fact the opposite - encourages bedding wear while providing good lubrication. In the good old days you would just use cheap supermarket oil that did not have good lube properties to run the engine in.

The Zinc additive is primarily for the cams - RV8s are notorious for cam wear and rounding the lobes, particularly if not run in correctly where the hardening can be quickly removed. It is here that the ZDDP additive gets into the cam metallurgy to help protect the cam lobes during the running in process and for the life of the cam.

Once all run in there is no longer a need to continue with additive.