John Deere S100 Oil Analysis
This small-engine case study summarizes a lab report for a John Deere S100 lawn tractor. The useful takeaway is conservative: the oil looked usable at sampling, but silicon should be watched.
What the lab data showed
The report used AMSOIL SAE 5W-30 synthetic small-engine oil and reported the sample at 83 hours. The cards below list the report values in readable page copy, with the report image included below for reference.
Use the result to reduce guessing, not to overpromise
The lab comment said flagged data did not indicate an immediate maintenance action and that the oil was suitable for continued use at sampling. It also called silicon a moderate-level item, so air filtration and future trend checks should stay part of the maintenance plan.
Confirm the exact equipment recommendation
Small-engine fitment can depend on the equipment and service condition. Use the lookup guide before choosing a product, filter or interval for a different mower or engine.
Common S100 case-study questions
Read the report as one equipment example, not a blanket service interval.
Does this report justify a universal three-year interval?
No. This case shows one mower sample at one point in time. The conservative use is to monitor future samples, inspect air filtration and follow the shortest applicable service rule.
What was the main watch item?
Silicon was reported at 52 ppm and the lab described it as a moderate-level item. Air-filter sealing and future trend data matter more than a single number by itself.
Should visitors copy this exact oil and filter?
No. Start with the Small Engine Lookup Guide when fitment, viscosity or filter selection matters.