We used a Teflon based grease from Hydrotex at work on heavy machinery. I have a partial box in the shop I purchased 12 years ago, but not sure they make the same exact product by name. Beat anything they had bought us before, and you could not beat it out of the pins. Not good in high speed bearing applications, but great in pins & bushings.
Pretty expensive, I paid $45 for a carton of 10 tubes back then. But there's probably 4 tubes left in the box, so it has been worth it to me.
On the job greasing the Kobelco 210 excavator every day, a box of 10 tubes would last me about 3 weeks. Where the cheap stuff they were buying would last me a week, greasing 3 times a day,and looked like a goose had been following you around.
The downfalls are, it is pretty stringy, which is a good thing. But you made sure you had a rag around the fitting when you pulled it off, or it would string out, into the wind. And, it did not pump well out of the gun, when it was in the low 30's, or below.
Here is a link to their site, and products.
Hydrotex - Your Lubrication Solution Partners - Hydrotex | Your Lubrication Solution Partners