6sally6 wrote:

I don't have the 'nadz' to breake one in on ATF.....
Dat wuz de udder feller.......
6sal6
 

I’m with you Sal, I wouldn’t try it.  I’m not saying it may not work, but I’ve broken in several engines through the years without any issues to try to use ATF at this stage of my life.

 

Last edited by BobE (2/12/2023 10:16 AM)

Here is Ford Racing's instructions on the M-6007-C347 that has been powering my car for the last 20 years: "The engine has been hot tested. The 20W50 factory fill oil should be changed after the break in cycle. Any good quality natural or synthetic 20W50 may be used." I have no idea what "20W50 factory fill oil" is and never bothered to ask Ford Racing for clarification.

This is my first and only "crate" engine, and I found these instructions ambiguous, especially given the fact that the engine shipped without oil. At the time, Ford Racing advised me that they run the engine under load until the headers are glowing red to ensure that the rings seat and that no further break in is necessary, except to retorque the head bolts as set forth in the instructions. 

This engine has been run hard over the last 20 years and runs as good as the day I installed it. I just drove round trip 500 miles last weekend with the only issue being a bad spark plug boot.

I think you will have difficulty finding consensus on breaking in an engine. When I build engines, I run them hard right away, as I have experienced rings that don't seat which requires removal and replacement. On the other hand, the C-8 Corvettes have an extended break in procedure. Moral of the story: Follow the break in procedure recommended by your engine builder. Alternatively, if you are building your engine, choose the method that makes the most sense to you.
Good luck on your project.


 

TKOPerformance wrote:

Interesting, I don't know of anything that uses 20W50.  Mercedes used to spec a 50W oil for their straight 6 gas engines, that might have been 20W50.  That's pretty heavy oil.  Years ago everything was 10W40, then 10W30, then 5W30, and now 5W20.  Even my Diesel runs a 15W40 or 5W40 synthetic.  I'd be curious what oil they expect you to run. 

When I was having difficulty finding 20W50, I called Ford Racing and the tech stated that 10W30 or 10W40 would be fine and I have been running both ever since. The Ford Racing instructions for the engine I am considering, M-6007-Z460FFT(FRT), calls for 10W30 or 10W40, so Ford Racing has made a change in the last 20 years.

I have valvoline 10w-30 in mine now.
 

6sally6 wrote:

Bearing Bob wrote:

Break in oil for a roller cam??? Never heard of having to do it. That's supposed to be the benefit of a roller cam. And for oil, search for what Ford recommends for your motor when it was new. Any brand will do.


Name a guy who had motor problems cuz of the brand of oil.

X-II
6s6
"If Walmart ain't got it.............I don't need it !!"
 

You still have to break in the rings and bearings.  There isn't a running in process like there is for a flat tappet cam, but its still good practice to change the oil at 500 miles, and avoid synthetic oil for break in and the first oil change.  Is a dedicated break in oil necessary?  Probably not, but then again, oil is cheap and engines are...