RBM 12 #1 Posted 16 hours ago Hello...I want to put shell rotella t6 5w-40 in my kohler k301? I just have seen people do this before...Will this better the engines lubrication system? Is it good insurance? What are your thoughts? Thank You. Share this post Link to post Share on other sites
Darb1964 1,167 #2 Posted 16 hours ago I have used 15w-40 in some of my kohler in the summer and they seemed to do fine with it. 1 Share this post Link to post Share on other sites
953 nut 65,134 #3 Posted 16 hours ago Your engine is splash lubricated with relatively wide clearances when compared to a modern automotive pressure lubricated engine, I would go with 30 as stated in the engine manual. 3 4 1 Share this post Link to post Share on other sites
clueless 3,379 #4 Posted 14 hours ago T-6 is not going to do anything better for you engine than T-1 (30w) or T-2 (40w). Full Syn and Blends in these old loose tolerance dirty port engines just burn off some of it after a couple of hours of use. Rotella T-6 is expensive overkill for these old flatheads. 1 2 Share this post Link to post Share on other sites
oldlineman 1,671 #5 Posted 14 hours ago I have used Rotella T1 30w for years, summer and winter without any problems. IMHO it is the best oil for these older engines that is made. Bob 7 Share this post Link to post Share on other sites
8ntruck 8,754 #6 Posted 12 hours ago I believe that the Rotella T1 was originally developed for use in diesel engines. It has a better extreme pressure additive package suitable for the higher bearing loads in compression ignition engines. When used in our antique Kohlers, and Onans, that same extreme pressure package helps protect our journal type crank and rod bearings and the non roller lifters and cam shaft. These surfaces have largely sliding type of friction. The current automotive engine oils are designed for tighter crank and rod bearings clearances - often with special coatings - and roller lifters running on the cam. All of these features are efforts to reduce friction and increase fuel efficiency, which, was not a concern when our antiques were designed and built. 2 2 Share this post Link to post Share on other sites
JoeM 9,741 #7 Posted 12 hours ago I use 5w-40 diesel oil in just about everything, one real advantage is the synthetic oils ability to transfer heat. And of course we are talking about air cooled engines. That oil is top of the line and will out preform just about anything out there. Most thoughts are built on old school thinking and not science. Part of my old job was closely tied to lubrication and we had a lot of sensors gathering data around the clock. Synthetic oils lowered internal temps up to 20%, at the first oil change. You have to remember those old service manuals were written over 30 years ago. Oil has come a long way since then, and if you want to use it, It will be fine. 1 1 Share this post Link to post Share on other sites
rick 287 #8 Posted 12 hours ago Does the Rotella T-1 have more zinc additive than normal 30wt oil? Share this post Link to post Share on other sites
oldlineman 1,671 #9 Posted 11 hours ago I believe so Share this post Link to post Share on other sites
RBM 12 #10 Posted 9 hours ago I have about 4qts of this oil...Is it fine to use will it damage anything or is it just unnecessary? Thank you. Share this post Link to post Share on other sites
ri702bill 11,768 #11 Posted 8 hours ago 4 hours ago, 8ntruck said: The current automotive engine oils are designed for tighter crank and rod bearings clearances - often with special coatings - and roller lifters running on the cam. All of these features are efforts to reduce friction and increase fuel efficiency, which, was not a concern when our antiques were designed and built. And their severe duty flat tappet ZDDP Zinc is 5% of what it was - due to the Zinc clogging catalytic converters. That is why modern car engines use roller lifters - no more flat tappets. Rotella still has a reasonable amount of zinc in it. Not recommended - using just modern multiweight motor oil alone. You CAN use it with a rather expensive zinc supplement added to it. Better off just to buy the conventional (not full synthetic) Rotella. TSC - $16 a gallon..... 3 1 Share this post Link to post Share on other sites