FWIW -- I'm running 15W40 (diesel oil) in my 261 because my engine's crankshaft was turned by a race engine rebuilder, thus it has greater tolerances in the mains.

Plus, that's what Jerry said to do and I follow his advice wink

~ John

A kid raised on Hotwheels, Matchbox and Tonka cannot be reasonably expected to own only one vehicle as an adult.

1949 Chevrolet 3804
In the Legacy Gallery | In the Gallery Forum
1973 IH 1310 Dump
1963 Kaiser M38A1
2001 International/AmTran RE3000 "Skoolie"
2014 Ford E-350 4x4 (Quigley)