35lbs at 210 idling at 800rpm. (I figured I would answer with my average high temps like idling in traffic) Lots of hydraulic systems are capable of running standard hydro oil in them, including transmissions and power steering units. If you have ever seen hydro static drive systems it becomes clear very quickly that the hydro oil is capable of lubing super high pressure mechanical pumps, drive motors and valving systems.
I asked Brian at IMM Engines what oil should I run in the engine he built for me. He said run 10w/30 oil that is high zinc. Joe Gibbs, Valvoline Racing oil, etc.. Now keep in mind this is a roller cam engine. Don't ask me why because I don't know the answer. I just do what the man said. LOL I run the engine some what hard so it gets fresh Joe Gibbs Driven 10w/30 oil every 3000 miles. If anyone wants to donate me some money for my oil changes I would greatly appreciate it.
Joe Gibbs racing oil ??????? If I was riding around in circles for 500 miles, I'd use it. But in the real world of daily use I wouldn't. Racing oil doesn't contain some additives that 'street oil' does. There is more to oil formulation than you'd think. Any oil that's listed SG on the label should work fine on an older stock engine with a flat tappet cam. Add a high lift cam with heavier springs, and you might want to do some research. [and drive yourself nuts at the same time]. Keep in mind that 340's would run 100,000 miles with oils that are not as good as todays oils. But they contained a lot of zddp.
If you really want to know how good your oil is working, send a sample to Blackstone Labs for analysis.
Brad Penn, grade 1 semi-synthetic. Can’t remember the weight. I believe they have been bought by someone and may have changed, but not sure. Was looking at the Joe Gibbs oils, but might just go Valvoline VR1.
I just run mobil-1 in everything I own including my mowers. In my 340 I run 15w50 Mobil-1 it already had the zinc and other additives a flat tappet cam needs and you can buy it by the jug at walmart
