My old1966 F-100 has 130,000 mile on it. Was wonder what weight motor Oil I should be using. It has the Original 240 cid engine. I have only replaced the Oil pump in it about 300 miles ago. It smokes just a little when going up hills.

 

10W30 nutten special should be just fine. You can spend money on all kinds of snake oil but with a well worn engine I'd stick with plain jane 10W30



John

 

Thanks..was not sure...I see out Oil for old engines..was not sure if I should use that...

 

thank you. I also resuscitated a 1965 f100 with its original 240 motor, 63k miles on it. it was a farm truck and sat abandoned in the dirt for 30 years. Motor block has a plate on it from Ford dealership saying motor was rebuilt. Truck is now completely new mechanically. I have been driving it daily for about 43 highway miles per day to work, all freeway. I have been using the 10w40 waltmart brand since it came back to life. Will start using 10w30 as explained here. No issues so far with the current 10w40 here in Phoenix AZ.





Thank you all
John [/QUOTE]

 

I would add some zinc to be on the safe side. Our flat tappet cams will thank you for it.

 

Old thread but...
Shell Rotella T4 15w40 Diesel oil

 

Old thread, but since we're here, Oil options are like a-holes, everyone has one and everyone is different... myself, I run Delo 15/40 in everything I have, since my 02 F350 runs it, everything runs it, never had any issues. I have generators at my Off-Grid sites that I switched to Delo, going on 23,000 hrs on them running it. Pick one, YRMV

 

As hot as it gets in Phoenix in the summer, using a 10w40 or a 15w40 wouldn't hurt a thing, and be more like a 10w30 in the rest of the world.