2 post lifts

Mine shop is on sand and bedrock but the lift is on sand. My whole floor is a 4" thick, six bag mix with fibermesh.

I have a 50 year old Weaver two post lift constructed of 3/4 and one inch thick steel bolted to the floor with one inch anchors. The lift itself is very heavy....likely in the 2,000 lb area.

I bought it used around 1994 and I've had loaded E350 vans on it and duallys without and issues.

I would think your area in GA has red clay. That may influence your concete pour.

I would find a local, professional concrete contractor and let them tell you what you need. And call the local installing dealer for pro lifts like Aamco, Monarch or Rotary. They will have your answers. Google is your friend.

You will get all sorts of different answers many from people just repeating what they have heard here and on the net. Not a bad thing but let the pros give you advice.

My lift is on 4" and my buddies Rotary is also on 4". No issues for me for in 35 years. And I used to use it on dozens of projects.

And don't just buy on price. A shiny new El Cheapo Chinese lift may not be a good value. I paid $1800.00 for mine and disassembled it and reinstalled it myself with my friends help. All you need is a square and a tape measure to get it right. Oh yeah a good set of anchors.

Good luck.