what grease is suitable for use in a vario tail gearbox

Use a good quality white lithium grease.

Taylor

A.K.A TayloMadeUAS.Inc

does it have to be white why not just lithium grease

I like to use white and Vario even sells it. I have been using it on Vario gear boxes for many years.

Taylor

A.K.A TayloMadeUAS.Inc

One of the reason's that Lithium White is white:

It uses a clay media as the carrier or binder substance to add the lubricant too.

One of the reason's it get's hard and dry when old or the lube leaves the binder clay media.

You may wish to pay a vist to a Large Electrical Motor Shop and see what they have for Pure synthetic's or EM rated product.

It's Pure Syn / has a High Pressure rating and is made for unlimited continuous duty under heat most are pretty low viscosity and High EP ratings

I use every thing as purpose specific: from graphite to Moly Disulphide to EM syn , Little application for White Lithium in my arena - but it's Uber Cheap.

greyeagle

I use Triflow clear synthetic grease (can withstand high temperature) on my DS615 servo. It works well.