hello,
this weekend I will hopefully finish installing a rebuilt engine into my 78 f250. The motor has never been fired, and I just want to make sure I'm doing everything right.


So, What oil should I use to break it in?
Any special additives I should put in to help break everything in?
how should I drive it, and for how long?


I've done a lot of reading on here about what oil people prefer, and I'm leaning towards the Diesel oil shell Rotella, but not sure what weight, and I'm still open to others, so what does everyone recommend? Its probably worth mentioning that I live in northern Minnesota, so I might be using different weight oil in the winter. I like running synthetic oil in my car in the winter since it gets so cold (-40 f isn't uncommon), but not sure if synthetic is good in these older motors?


thank you in advance for any help!
Tyler.

 

Oil & Lubrication - Ford Truck Enthusiasts Forums

There is your oil Forum

 

I'm trying to get information a little more specifically for the .300 I6, my apologies.

 

If you are using a new cam and lifters use the additive that the cam manufacturer recommends/supplies.

Otherwise I use a nationally recognized brand of 10W-40 with a quart of synthetic 10W-40 of the same brand.

Good to go in excess of 7000 RPM. No oil related failures in 50 years of racing/rod building.

 

If you don't plan on any 7000 RPM excursions and are obsessed with getting optimum fuel economy you can use 10W20 or 30, or even full synthetic if you have money to burn.

 

I heard to not use synthetic until the engine is broken in. That synthetic is so good, that it prevents wear or something like that.

 

I've heard this too. The idea of the break-in process is for all of the imperfections in the rings, cylinders, etc. to wear together to create a better seal. (If everything was flawlessly perfectly smooth and round, there would be no need for a break-in process.)

The synthetic can prevent this from properly taking place.

Once the break-in is done though, by all means...

 

15-40. (has zink)
change oil after 500miles
change oil after 1000miles.

How I do it.

 

And after that, switch to synthetic!

Love that synthetic stuff! No way I'd run an engine without it, no conventional oil for me

But I do live in the sub-arctic which helps with engine starts.

 

Don?t Fall For The Myths! - Driven Racing Oil

 

Excellent article...Thank you!

 

Well.. the 300 lasted 40yrs on normal oil and was still running..
I'll just do that again. lol