Segway gear oil

[Civicsman]

Now need new oil, this is transmision oil from class GL-4, like 75W-90, 80W-90 and 85W-90. The last one is only for areas with very low temperatures.

I don't know whether these numbers are valid for a Seg, but in the general case, shouldn't the lowest viscosity oil (75W-90) be used for lower temperatures?

Personally, I don't think changing Seg gear case lubricant is necessary, or even advisable, especially at low mileage. Gear case / transmission oils for automobiles last MUCH longer than engine oil, which gets contaminated by combustion blow-by and moisture.

Also, keep in mind that seals that are used for petroleum oil may react poorly when exposed to some synthetics. One could end up with a much worse problem.