Ngl I still prefer lithium grease over synthetic on most gearboxes

I know everyone's been raving about all synthetic everything for years now, but I've been doing this since 2008 and lithium grease has never let me down. Last month I repacked a gearbox on a King Air 200 that's been running on lithium for 12 years straight. Opened it up and the gears looked almost new. My buddy swears by the synthetic stuff and he's replacing seals twice as often as I am. Is there something I'm missing or are we just getting upsold on fancy marketing?

2 comments

2 Comments

wells.reese20d ago

@the_lucas brings up a great point about that old truck stop smell, and honestly it makes me laugh every time I crack open a can. But the smell is a small price to pay for something that actually works. The thing about lithium grease is it doesn't break down as fast when it gets hot or when water sneaks in, which is exactly why the King Air I worked on looked so clean inside. Synthetic grease has its place, sure, but for gearboxes that see a lot of stop-and-go or sit for long periods, lithium holds up better in my experience. I think the younger mechanics get pushed toward synthetic because it's newer and the manufacturers push it, but that doesn't make it better for every job. Just my two cents from twenty years in the field, and I bet @the_lucas would back me up on the seal thing too.

the_lucas20d ago

You ever had to explain to a younger mechanic why you still use grease that smells like old truck stop? I ran lithium on a Cessna 414 gearbox for eight years and never touched the seals once.