# Synthetic Oil in Disc Mower Cutter Bar/Gearbox



## dvcochran (Oct 1, 2017)

I recently purchased a one-year-old John Deere (Kuhn) disc mower. I plan to change the oil/grease in the cutter bar and gearbox before cutting this year. I am wondering if anyone is running synthetic oil and if you have seen any benefits or problems. The manual calls for SAE 80W-90 with API service classification GL-5.


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## 32-0-0 (May 30, 2017)

I bought a Kuhn 800 about 7 years ago and have not used synthetic gear oil. I change the oil out after 200 hours as recommended by manual and have not had any issues.

Mine is not on a dolley and it was never much fun hooking and unhooking it. I finally bought adapters for the hitch pins and now use a quick hitch. Even with the quick hitch it still isn't super easy, but I finally figured it out. Sorry for getting off topic.


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## FCF (Apr 23, 2010)

I have a NH 1409 and the first time I changed oil in the cutter bar and gearbox went to synthetic. Used Amsoil severe gear of the weight called for in the manual. Have not had any problems, nor have I seem any huge benefit other than longer drain intervals.


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## Goldenstables (Jan 19, 2019)

The new Kuhn’s all run synthetic lube in the bars and gearboxes.


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## SCtrailrider (May 1, 2016)

I run TriboDyn synthetic in mine, it's great lube and I'm a dealer for it...


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## endrow (Dec 15, 2011)

There is a Ag repair shop in our area . they repair equipment and tractors . The guy that runs the show there has seen a lot and is pretty sharp. He says in ag applications synthetic oil is good but if you use it do not extend your drain intervals . that never pays in ag applications , from what they have seen in there shop .


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## Trillium Farm (Dec 18, 2014)

I agree, use synthetic because it lubricates better under most circumstances, but do not extend the OCI


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## chevytaHOE5674 (Mar 14, 2015)

I run shaffers synthetic 75-90w in my discbine. When checking the cutterbar temp the operating temps have been cooler since the switch. For as little oil as it holds the cost isn't too bad so it's worth it to me.


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