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4 post lift owners: how plumb are your posts?

AugyIA

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Mar 11, 2021
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I recently installed a 4 post storage lift in my garage. It's the typical 8000 lb model with removable casters for ease in moving. I've got it sitting on Racedeck flooring, free standing (not bolted down). I got the runways leveled using the cable adjustments and ladder stop adjustments. I've seen many threads about sloped floors (for drainage) and I was able to get the runways leveled using information from those threads and it really wasn't overly difficult.

That said, the posts are not perfectly plumb and I'm wondering how critical it is that they be perfectly plumb. I figure the posts will flex some with the weight of a car on it so if they are plumb with nothing on it...they are likely to be less plumb once you raise a car on it.

I am trying to decide if I should bolt it down using shims (C shims) under the post plates to make them plumb. If I do that, I'll have to cut the Racedeck floor tiles around the 4 posts base plates. I'd prefer not to bolt it down as I like it resting atop the Racedeck floor and, while I don't anticipate needing to, bolting down would negate the ability to use the casters to move it.

So, my question is...for those of you who've had 4 post lifts for an extended time, how plumb are your posts and/or is this something you'd be highly concerned about? Any other thoughts on the subject? Thanks in advance for any help or insight.
 
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Yankeefarmer

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I’m not sure what a “typical” 8000 lb 4 post lift is. Does it have “C” channel posts with ladder type lock bars, or full square tubing posts where the safety lock slots are cut directly in the posts themselves? Reason I ask is I have an Advantage DX-9000XLT lift, and the manual that came with it specifically recommends not bolting it down. I’ve not noticed any “out of plumb” with or without a vehicle on it.
 
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AugyIA

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Sorry, I should have been more clear...it's the C channel post with ladder bars...Atlas, Triumph, Tuxedo, AutoLift, and a dozen other companies all sell the same (or very similar) model, very common hobbyist 4 post lift. It comes with shims and bolts but states it does not have to be bolted down.
 

racecougar

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Forward EFP9 / Direct Lift Pro Park 9 Plus owner here. All four posts are plumb in both planes per a 2' bubble level (didn't stick an angle finder on them). My floor is very level/flat, with no slope. I chose to put two bolts into each floor pad just to make me feel more warm/fuzzy about stacking valuable cars, and it significantly reduced the amount of "wiggle" when wrenching under a car on the lift.

I like to be able to move my lift when needed for a project, so I went with drop-in anchors which sit below flush. I can unbolt the lift from the floor and move it without leaving any trip hazard behind.

https://www.homedepot.com/p/Red-Hea...m9v_Idqx3uy7gm1fxHwaAsv9EALw_wcB&gclsrc=aw.ds

I shuffled my feet on bolting the lift down for nearly a year, but now that I have, I'm glad that I did it. Again, I only put two fasteners per post, and it made a noticeable difference in how rigid the lift feels with a car in the air.
 
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AugyIA

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Ok, thanks. I think I'll go ahead and bolt it down. I don't have enough room to really move it around anyway and the idea of making it feel more solid is appealing :)
 

Chevy-SS

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I have 9,000lb capacity, 4-poster by Challenger. Initially installed it unbolted, within a week had mishap which ALMOST collapsed the lift and would have resulted in tons of damage, if not death. It was my fault, but it would not have been as dangerous IF I had bolted it down. Needless to say, I had the crew come back in and shim/bolt it down. It has worked wonderfully ever since (7 years).
 
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AugyIA

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Yikes Chevy-SS, that gives me even more reason to bolt it down. Thanks for sharing...glad you were able to avoid disaster!
 
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AugyIA

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I really like the idea of drop in anchors rather than the wedge anchors that came with my lift. The wedge anchors I have are 3/4" but you linked 1/2" drop in anchors. I suspect it wouldn't matter a lot as either size is going to keep it in place and it's not really doing anything other than preventing it from moving laterally. Just curious if your lift called for 1/2" or if that is just what you can find locally? I may just drill through the slab and use the wedge anchors knowing that when I move I can just drive them through and patch the holes. Either wedge or drop-in should work and I think I'll feel a whole lot better working under the lift.

Thanks again.
 
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LX-Markham

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I figure the posts will flex some with the weight of a car on it so if they are plumb with nothing on it...they are likely to be less plumb once you raise a car on it.

The posts should not flex at all. They are axially loaded. At least the BendPak ones are, not sure about the Atlas.

Having the posts plumb ensures the axial load doesn’t cause any eccentricity on the posts. It also ensures that all four posts are parallel.
 
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AugyIA

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The posts should not flex at all. They are axially loaded. At least the BendPak ones are, not sure about the Atlas.

Having the posts plumb ensures the axial load doesn’t cause any eccentricity on the posts. It also ensures that all four posts are parallel.

Thanks, that makes sense (after I read it three times) :) I am probably over-thinking it but figure it's not something I want to take much risk on and having it as perfectly plumb as possible will be safer and prolong it's life (and mine!).
 

racecougar

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I really like the idea of drop in anchors rather than the wedge anchors that came with my lift. The wedge anchors I have are 3/4" but you linked 1/2" drop in anchors. I suspect it wouldn't matter a lot as either size is going to keep it in place and it's not really doing anything other than preventing it from moving laterally. Just curious if your lift called for 1/2" or if that is just what you can find locally? I may just drill through the slab and use the wedge anchors knowing that when I move I can just drive them through and patch the holes. Either wedge or drop-in should work and I think I'll feel a whole lot better working under the lift.

Thanks again.

Those are just the first ones I quickly found a link to via Google simply to illustrate. I don't recall what size I went with off hand.
 
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Glemon

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I wasn't going to bolt mine down, but probably will. It is pretty wobbly with no car, actually firms up with the weight of a car holding it down, but would feel better with it anchored, especially if I start doing some serious work with a car on it.
 

muckdp

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My rotary 14k is bolted down, and is plumb with or without a load on it. I like the idea of using a few easily removable fasteners if you think you may want to move it around.

Good luck!
 

Jeepster04

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I have 9,000lb capacity, 4-poster by Challenger. Initially installed it unbolted, within a week had mishap which ALMOST collapsed the lift and would have resulted in tons of damage, if not death. It was my fault, but it would not have been as dangerous IF I had bolted it down. Needless to say, I had the crew come back in and shim/bolt it down. It has worked wonderfully ever since (7 years).

Care to explain what happened so others can avoid such a situation?
 

SHOCheapRacing

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Bel Air, MD
I did not bolt mine down, but drew around the stands to see if it moved. I was surprised how much each corner walked, but once it seemed to settle in its current spot it has not moved at all. Yes you can really get the car shaking up in the air.

My biggest concern about not bolting it down is missing one of the locks on the way down. The front two caught and the backs tried to catch on the next lower lock. I could not see it while was lowering, but noticed some dip with the car. One corner post really started to lean in toward the center and it looked really bad when I walked around the car.

Never going to make that mistake again, put painters tape on each corner for each car (low ceiling).
 
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AugyIA

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This happened to me, as well. Luckily, it was during initial set up and I had nothing on the lift. I was able to adjust the ladders to make all 4 corners lock at the same time. I can only imagine the fear it would instill with a car on it at that moment.

Thanks for all the feedback. I'm either going to use the wedge anchors that came with it or purchase some drop in anchors. I don't plan to move it so using what I already have is probably the way I'll go.
 

racecougar

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If you use wedge anchors, I recommend drilling all the way through your pad so that you're able to tap the anchors down flush if you do ever decide to move the lift. It's easier than cutting and grinding them flush.
 
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AugyIA

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If you use wedge anchors, I recommend drilling all the way through your pad so that you're able to tap the anchors down flush if you do ever decide to move the lift. It's easier than cutting and grinding them flush.

Yep, that's a good idea and what I intend to do.
 
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AugyIA

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I put 2 wedge anchors on each plate last weekend. I may go back and put the other 2 in but the difference is astounding in how much more solid it feels. Drilling concrete isn't much fun or I might have done all 16 :) Regardless, it just feels a lot more solid and safer now. The posts are all plumb (or very, very close) now and that also gives me a warm fuzzy feeling.
 
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