Audioshot 2 #1 Posted January 23, 2010 Hi, I'm new to these forums and found it very informing. I recently purchased a 1991 Wheel Horse 310-8 for $200. It has not seen much use but was rather dirty. I stripped the whole thing down to the frame and cleaned, re-greased, rewired and painted then assembled it back together. Man what a machine! Very powerful and solid. It didn't need much, just basic parts like belts and throttle cables and some electrical stuff. My question is, what motor oil does everyone run in the Kohler Magnums? I know the manual calls for straight 30w API SF, however, it is very hard to find the API SF these days. I have been hearing a lot about the newer API SM with drastically reduced anti-wear additives zinc and phosphorous. I guess on flat tappet motors (like the Magnum) it can (or might) eat the cam. The solution was to run Diesel 15w-40 API CI-4, however as of last year, the diesel oils have to comply with EPA and then came out with CJ-4 that also has the reduced zinc and phosphorous. The only oil available in a straight HD 30W is SL rated. I'd like to run synthetic but the only oil with high zinc is Mobil 1 15w-50 and 50w might be a bit much for a slinger to splash the oil around and get into tight spots and bearings. I don't know, maybe I'm just paranoid. Any thoughts? Thank you Audioshot Share this post Link to post Share on other sites
gwgdog66 23 #2 Posted January 23, 2010 :thumbs: I sent you a PM Share this post Link to post Share on other sites
rickv1957 75 #3 Posted January 23, 2010 Hello and I have been using castrol 10w40 for 30 years and never had a problem,Rick Share this post Link to post Share on other sites
