I know Stihl sells their own but is there a grease that's compatible for greasing the gear head?

Put zert.. on and use whatever grease you got. Grease 2 times a year. Remove zert when done

 

Funny thing about this. I asked my dealer about the grease, and my dealer suggested I put on a zerk like all of the other brand trimmer heads they sell.

They did however still have the grease for the hedge trimmer gearbox, which is different.

Anyway, when it comes to greasing a gearbox, less is more. Too much grease leads to overheating.

 

How much grease?

 

Just a few pumps...

 

https://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=212587

 

Sthil sells a tube of greast that screws into the bold that you remove.

Ive never greased mine, 10 years old.

 

My problem with zerks are they break off. And yes, over greasing is a definite drawback.

You don't leave it on...and hardly possible to overgrease but highly like to undergrease unless you rotate gears....i have NEVER had one blow up from overgreasing

 

One option is to use a button head grease zerk. Those don't break off, though you need an adapter for your gun. I know I saw these on one manufacturer's trimmer heads at my dealer (can't remember which).

I can't say that I've seen a trimmer head blow up from overgreasing, but I have seen gearboxes fail from it. In most of the trimmer heads I've seen, the shaft bearings are unshielded, so as pointed out above, overgreasing the box will force the grease up the shaft. But it will also cause the box to run hot, and will put unnecessary drag on your engine.

However, trimmer gearboxes are the exception for me. Most every other greased gearbox I work with uses sealed bearings on all sides, and overgreasing will eventually blow out seals, but the effects of overgreasing start long before the seals are blown out.

 

Some leave them on. And where did I say, anywhere, that they can blow up from over-greasing?

 

So ricky what is the worst case from over greasing?

Been watching this, this topic intrigues me. I feel like I am always putting grease in my head sooner than I have to. And when I do, I screw in the stihl tube and squeeze the crap out of it till it is full. I feel like if I were to use the grease I use in my gun for stuff on my mowers it would last longer. But it is an NLGI 2 grease though

 

interesting. Perhaps I am greasing it too much then. Not that I think mine has it going up the shaft or anything. When I changed the head this year there was just a little bit there that has squeezed through where the output shaft exits the box. But when I notice the sound from the trimmer changes, like a whine, and at the end of the season... that is when I grease it.

I did not pay as much attention to the idea of the grease traveling up the shaft as you had stated as much as I did the other suggestion someone made of excess heat.

 

i grease them like once every 2-3 years at the most. the grease stays in there forever. you could probably wait 5 years. by then the trimmer is junk anyways. :laugh:

i grease the flexible cables on the edger attachment every year though.

 

Can I just use any grease? I have the lithium based Lucas red. Or I have valvoline cerulean.

 

If the Lucas is the red and sticky, no, I wouldn't. I don't know what the other grease is. Valvoline 609 is very close to Stihl's grease.

 

I’ve never greased a single trimmer.....ever. Never had a problem either. My trimmers see a lot of use....are usually pretty worn out after 3-5 years.

 

I've never greased a single trimmer.....ever. Never had a problem either. My trimmers see a lot of use....are usually pretty worn out after 3-5 years.

And this is more the rule than the exception.