I own a 14 oz grease gun but rarely use it as a home mechanic. I prefer the smaller 3 oz cartridge gun especially on my back under a vehicle, it's easier to maneuver. Something like this:
https://www.amazon.com/Slippery-Pete...dp/B07P67WLZP/
To me, you have grease, and marine grease. Since finding marine grease years ago it's the only thing I buy, works great in non-marine applications as well and since it: "Provides rust and corrosion protection in both fresh water and salt water environments" which pretty much describes the bottom of a vehicle, it is the only grease I buy anymore.
https://www.amazon.com/Lucas-Oil-106...dp/B00O7CLV1O/