4 post drive on lift questions and options
 

So my new garage will have a "post tension slab" cable system in the concrete and any drilling of the concrete floor will void the warranty of it. I am struggling with not only finding the exact locations of the cables before the concrete is poured so that I do not damage them if I decide to install a two post lift vs just bowing to the pressure from all sides and putting a 4 post lift in that will not require drilling the floor.

This thread is more about those said 4 posts lifts...

I'm looking at this lift. http://www.gregsmithequipment.com/At...-Sliding-Jacks

It is long enough and has the capacity to lift my ex-cab long bed truck and also lifts high enough for me to walk under it without banging my noggin. It also comes with two hydraulic RJ 35 sliding jacks with arms that will slide out to get under the real lifting points of most vehicles. Does anyone have experience with using these jacks in a real world scenario and if so, do you like or dislike them and why?

All the way down they are 3.5" tall which should be low enough for me to get any street driven car over them with ease. They have locks on them which will allow them to serve at jack stands if the vehicle needs to be off the tires for an extended time. It all seems good and sounds like a decent alternative to the two post lift that I have and love now...and even has some features that will be better than my two post (like being able to get the lift perfectly level for suspension setup purposes).

Buying this 4 post lift eliminates some huge hassles in regard to drilling my new floor, I guess I'm just trying to make sure I'm not creating more (different) hassles in using it once I get it installed. Space is not an issue, the new shop will have way more room than I'll need for any lift I choose ( :D ). I am picking electrical outlets this morning so if I need a 30 amp 220v for the two post, now is the time. That's the other nice feature of this 4 post lift...it runs on 110v.

Any thoughts from those that have used one similar to this?

http://www.gregsmithequipment.com/Pr...OJACK35-03.jpg

http://www.gregsmithequipment.com/Pr...OJACK35-45.jpg

http://www.gregsmithequipment.com/Pr...OJACK35-44.jpg

http://www.gregsmithequipment.com/Pr...OJACK35-39.jpg

http://www.gregsmithequipment.com/Pr...OJACK35-38.jpg

GPRS if you want to locate the cables after you pour. Ground Penetrating Radar system. You can call a local concrete cutter or Concrete coring contractor and they can get you to the people who can perform this. We do this all the time when building Hi rise buildings when a contractor misses a location in the slab.

http://www.groundpenetratingradarmis...s-City-MO.html

4 Post
 

You can buy a 4- Post lift that does not need to be anchored to the floor. Mine has casters you latch on it to move it if needed. It has been free standing and in use for 20 years. Never had a problem.

Yes. ^^^^. A pricey service, but if u nick one of these cables when drilling the holes for the lift, u DO NOT want to know what happens. I've seen some knarley videos (cutting a kitchen in half, another a person in half (older you-tube adult only access, mainly construction accidents where people were seriously injured or killed.)

Have the floor x-rayed after installed and compare that with current shop notes/drawings for cross reference.

With caution, mike

The builder will NOT provide any measurements or pics of said cables before the pour. They are VERY careful about this... They also will not allow anyone but me on site between cable install and concrete pour and I'm not sure I'll be able to be onsite that one certain day to view the cable layout.

Above and beyond that...drilling the floor automatically voids the warranty, no questions asked.

As much as I like a two post lift, I think my best option may be to just go with the big bad 4 post lift with two sliding jacks.

I've used smaller more simple drive on lifts in the past and they were a PITA to do any suspension work on. Way too hard to get bottle jacks on the jack trays and under the car's lifting points and the ramps were always in the way. Hopefully these hydraulic jacks solve that irritating issue.

My question is why that style floor ....why not a floating slab ....i.e footings around perimeter and then the concrete floor aka slab

So the floor hasn't been poured yet? Just build some anchor plates with the bolts already in. Just align and stick in the slab before pouring.

I have a similar 9000 pound tall wide four post lift. I also have a two post lift. I would take the two post lift over the four post by a wide margin. The ramps on the four post are quite wide and always seem to get in the way. It is also slower to raise. I use the four post to measure driveshaft lengths and driveline angles etc and also to do oil changes. Everything else is done on the two post lift.

Your builder should be able to share the slab drawings to locate the cables. If not they are easy to locate if you look for the grout plugs on the side of the slab.

Don

I'm curious about the use of that style floor as well, not common in my part of the world....commercial hi rise yes, but not residential. Hmmm.

As far as the lift, I got nothing. :)

I have had a 4 post lift for years and have that exact sliding jack platform. It is awsome. Bought a two post lift a year ago and hardly use it. I prefer the 4 post. Just drive on and lift. No crawling on the ground all around the car getting the 2 post arms in just the right spot. a 4 post can also be rolled outside if your door is high enough if you want to pressure wash under the car.