Ok break in process is over on this new rebuilt 401. I ran Brad Penn 30w break in oil. I bought a case of 12 quarts, i have already changed the oil an put in more of the 30w break in oil that i had left over out of the case. Will this hurt it? What weight should i run from now on?
I use the Brad Penn 10w40 in my 350. motor oil is like religion or pick up trucks, it will cause a debate every time. To be honest I am I diesel/heavy equipment mechanic and I have used 15w40 diesel oil in my 2002 F150 for about the past 10 years, bought it new. I calls for 5w20...... I just cant bring myself to run that low a weight oil in it. It has 140,000 miles on it and runs like a top, I passed it on to my son. My daughter runs a 2008 Mercury Mountaineer with the 4.0 V6, it calls for 5w30, it was burning oil, smoking, on start up, it has 130,000 miles on it. I started running the 15w40 in it and it quit burning oil, not really sure why????? What I am trying to say is that if you use a good brand oil and change it often your engine will be happy..... The Brad Penn has zinc in it which our older engines like, Plus its made in Pennsylvania!!!!!
Unless the engine is highly modified with heavy valve springs, then any oil will give good service. Some are better and zinc is not that important: https://540ratblog.wordpress.com I use 20-50 castrol in Texas (high speed, A/C, high temperatures, 'loose' engine)
10w-30 is a good starting point in moderate temperatures if you have decent oil pressure. If oil pressure is on the low side, you can try the thicker 10w-40 to help improve pressure. The straight 30 is okay but not ideal for cold temperature use. How's it running?
We run Amsoil Zrod 10w30 in ours. Just make sure it has zinc. Lots of choices. Many people here swear by Brad Penn.
Ok thank you everyone for the info,an she is running great just wanna make sure it stays that way,lol! Someone had told me the same thing though about running 10w-40 if oil pressure was low but which my aftermarket sunpro gauges might be off but it says 10-15 in idle an 30 psi cruising. Being a new engine i wouldn't say that is acurate especially how she drives. Im going with 10w-30 Brad Pen then next go around. Definetly believe in the zinc for this flat tappet cam engine! She is definetly came a long way!
That oil pressure sounds about right. The 401s in my limited experience seem to turn out a lower oil pressure than you would normally think of. However the rule of thumb I have been taught is you need 10psi of oil pressure for every 1k rpms you are turning. Before I had to pull my 401 I want to say it was running 15-20psi at idle and 35-40psi crusing at 60-65mph.
