4 post lift on a sloped garage floor...

Dakota00 · Mar 28, 2014

I've been doing some reading and gathering installation info on 4 post lifts.

Reading some of the installation manuals online on how to install a lift. One manufacture says that the runners and posts must be level from front to back. Then another section of the read, same manufacture, they say anything more than 1/8" or 1/4" of slope in 12" the lift must be bolted down. WTF?!?! Which is it??

Here's my situation...

I plan to bolt down the lift, which isn't the concern. My concern seeing that I got a pretty good slope on my floor. I haven't checked exactly how much it is, I'm guessing in the 3.5" to 4" range in a span of 20ft. How much slope is too much?
Would the lift work mechanically fine and safety if the runners and posts are sloped with the floor? I would prefer not to raise the 2 front posts of the lift 3-4" to make it level if I don't have too. I think this would also raise issues with the ramps and clearance issues for my vehicle.

It would be great to hear and see pics of your lift installation on a sloped garage floor.

tdkkart · Mar 28, 2014

Most of the better lifts are adjustable in a couple ways.
#1 cable adjustments which are adjusted so the ramps are level with a vehicle is lifted and hanging from the cables.

#2 Adjustable lock ladders....the better lifts have these, My Direct Lift has them, Bendpak has them. Most lifts have several lock positions that the ramps can sit on and have the weight off the cables.
On the cheaper lifts these positions are fixed with the stop blocks simply welded to the corner posts, which are then non-adjustable. With the ramps sitting on the locks the vehicle may or may not be level depending on the level of the floor.
The better models use lock ladders which are typically adjustable so that the ramps can be adjusted level while sitting in each lock position.

My floor has approx. 2" of slope front to back over 24ft. The installer was able to adjust the ramps level both while hanging on the cables and while resting on the lock positions.
When all the way down there is more slack in the front cables than the back ones, and when I start lifting the rear of the lift raises approx. 2" before the front lifts.
I suppose if the slope was too extreme you could end up with a bind between the posts and ramps when the lift was all the way down.

Dakota00 · Mar 28, 2014

^^^ Yeah I know about the cable adjustment and adjustable lock ladders. which works great for minor slopes. I'm looking to get a Direct Lift Pro Park 8. The ladders have up to 2" of adjustments for unlevel floors. I went out to check the slope of my floor, was stunned to see it actually 6.5" of drop in 20ft!! Which works out be less than 3 degrees of slope.

Dakota00 · Mar 29, 2014

bump... no one installed a lift on a sloped garage floor?

getthewheelsinline · Mar 30, 2014

I guess this is ramp depending......

Im based in the UK and purchased a 3Ton 4Post ramp which uses lead screws / chain to raise & lower the ramp via an electric motor. The lead screw nut at each post can be adjusted to ensure all the nuts are level, even though the nuts are at different heights in there corresponding lead screw.

excavator · Mar 30, 2014

I installed my Bend Pak HD9 in my garage with a 3 inch slope.
I did not bolt it down.
I shimmed up with steel plates on lower end to get it level
I shimmed with thin plates on high slab end to get post plumb.
All four post are plumb
there is still a 1/2 inch slope on runway's but it works perfect.
It does not move or rock at all with weight on it

Kevin54 · Mar 30, 2014

Dakota00 said:
bump... no one installed a lift on a sloped garage floor?

My nephew did at his shop and the thing buckled on him and he dropped a car off of it.

If you have that much slope (which is a hell of a lot), I would have four plates made up to compensate for the angle so when bolted down, your post are plumb.

junkman104 · Mar 30, 2014

I don't want to sound stupid but why does a garage floor have that much slope?

Or is it a northern thing?

Dakota00 · Mar 30, 2014

excavator said:
I installed my Bend Pak HD9 in my garage with a 3 inch slope.
I did not bolt it down.
I shimmed up with steel plates on lower end to get it level
I shimmed with thin plates on high slab end to get post plumb.
All four post are plumb
there is still a 1/2 inch slope on runway's but it works perfect.
It does not move or rock at all with weight on it

Hey excavator,

I would love to see pics if you can provide them!! Others with pics are more than welcome to post!!

Kevin54 said:
My nephew did at his shop and the thing buckled on him and he dropped a car off of it.

If you have that much slope (which is a hell of a lot), I would have four plates made up to compensate for the angle so when bolted down, your post are plumb.

Hey Kevin, I've been reading anything over 1/8" of slope on 12" should be bolted down! I take it your nephew didn't bolt his lift down. BTW, also read in one of the manuals that the lift is fine to be used on slopes that are no more than 3 degrees. My floor is within the limit.

Other problem that will arise "if" the posts are plump, the 2 lower posts where the car enters on the ramps will probably be 4" higher than grade leading to ground clearance issues for the car to get on the runners.

junkman104 said:
I don't want to sound stupid but why does a garage floor have that much slope?

Or is it a northern thing?

It's kinda a northern thing. In my particular situation I have a cold cellar under 1/3 of the garage. So to accommodate the head room and to make grade in the front of the garage doors the floor was sloped more than needed to make everything work. I checked my parents garage floor yesterday they live in the same subdivision 5 min away. Their garage similar to mine 20'x20' with no cold cellar underneath the slab has close to 6" of slope.

domer911 · Mar 30, 2014

I have a 4-post on a sloped floor and I did nothing, unless the installers did during installation, to adjust for the slope. My lift is not bolted to the floor, but it does "scoot" over time downhill (very very slight slope). I bought casters just so I could move it back occasionally. I've had to do that once in 8 months.

Kevin54 · Mar 30, 2014

Around here they slope the floor to let any water run out. My floor is only sloped about 2" in 28' though.

tdkkart · Mar 30, 2014

1/8"/ft is not uncommon here, so 3" in 24ft is not unusual and I've seen much more than that.

So get some "leg extensions" made. 2 plates the same size as the base plates on the legs with a short piece of tubing in between.

Bob C · Mar 30, 2014

Shoot the floor with a transit and install full size shim plates under all low corners. The slope has nothing to do with a 4 post lift buckling.

Relax · Apr 11, 2014

Here's what one person did to level the 2.5 inches of his slope. I'm really hoping I don't have to do the same thing. Maybe Jeff (JSK) can chime in on this?

http://www.chevyhhr.net/forums/showthread.php?t=28714

JSK · May 23, 2014

TDK nailed it.

• The cables should be adjusted so the runways remain level when the lift is operational – suspended.
• The adjustable safety lock ladders should be adjusted so the runways remain level when the lift is resting on the locks. Adjustable lock ladders (on many models) can be adjusted so the ramps will be in a level position when resting on the safety locks. You will only get about 2-1/2” of adjustment though. Any slope greater than 2-1/2” should be compensated for by using shim plates under the low-side columns. When the lift is resting on the floor there will be more slack in the high-side cables but the slack will disappear as soon as the lift is raised. The low-side of the lift (taught cables) will rise slightly before the high-side.
• If you use shim plates on the entry-side of the lift it can introduce ground-clearance issues so be sure only to use shim plates if you have more than 2-1/2” of slope.
• Let’s assume you have 6” of slope. I would use 3-1/2” of shim plates on the low-side then adjust the cables and ladders accordingly to compensate for the remainder of the slope.

Dakota00 · May 25, 2014

Jeff, thanks for chiming in...

What you stated is exactly how I'll be tackling the sloping issue I have. After looking at my options I've decided I'm going to raise the low side columns by 2" with shims under the plates and then adjust the ladders and cables to compensate the rest of the slope. The lift I just purchased has 4" of adjustments.

SteveCh · May 25, 2014

Good idea. I would want to shim the posts even if the manufacturer said the lift was ok on the slope floor. Some steel shims are extremely simple and a level lift is the way I would insist on going if it were my install.

topdowneh · Sep 5, 2014

Dakota

How have things worked out? I am in the exact same situation. Putting a 4 post lift in a double garage in a new house in Port Dover. Builder wanted to put a 4" slope in 20 feet of garage and I have convinced him to make it a 2" slope. My car is quite low and I do not want to add a 2" shim to the front feet. I would think that if I lay the lift as is on this floor, it should not be an issue. This would mean that the posts would not be perfectly vertical, but angled slightly towards the garage door.

I won't be picking up the lift until the end of Nov from the Super Lift Store in Oakville.

Dakota00 · Sep 5, 2014

topdowneh said:
Dakota

How have things worked out? I am in the exact same situation. Putting a 4 post lift in a double garage in a new house in Port Dover. Builder wanted to put a 4" slope in 20 feet of garage and I have convinced him to make it a 2" slope. My car is quite low and I do not want to add a 2" shim to the front feet. I would think that if I lay the lift as is on this floor, it should not be an issue. This would mean that the posts would not be perfectly vertical, but angled slightly towards the garage door.

I won't be picking up the lift until the end of Nov from the Super Lift Store in Oakville.

In the end I got the lift to workout just fine. I had to shim the front posts 2" and adjusted the front ladder locks another 3". The lift is almost level, when lifting and in the locking position.

As for your situation 2" on 20 feet is not an issue, you can level your lift just fine.

Here's a pic of mine...
View media item 41594

Slowbra · Sep 6, 2014

I agree that 2" in 20' is not an issue. I followed the instructions other mentioned when leveling mine and everything worked out great without shims. Mine was slopes more than 2" over 20'.

volleyball · Sep 6, 2014

topdowneh said:
Dakota

How have things worked out? I am in the exact same situation. Putting a 4 post lift in a double garage in a new house in Port Dover. Builder wanted to put a 4" slope in 20 feet of garage and I have convinced him to make it a 2" slope. My car is quite low and I do not want to add a 2" shim to the front feet. I would think that if I lay the lift as is on this floor, it should not be an issue. This would mean that the posts would not be perfectly vertical, but angled slightly towards the garage door.

I won't be picking up the lift until the end of Nov from the Super Lift Store in Oakville.

Why not have the section where the lift going made level and leave the rest sloped?

Codybear · Apr 14, 2015

JSK said:
TDK nailed it.
• The adjustable safety lock ladders should be adjusted so the runways remain level when the lift is resting on the locks. Adjustable lock ladders (on many models) can be adjusted so the ramps will be in a level position when resting on the safety locks. You will only get about 2-1/2” of adjustment though.

But Figure 3.7 in the HD-7 and HD-9 manuals state:

"Tighten the top nut on each safety ladder until one inch of threads are exposed and the ladder is raised at least 1/2" off of the base of the column."

"WARNING: DO NOT raise the ladder more than one inch off of the base of the column or damage to the lift will result."

This would suggest that a maximum adjustment of 1/2" is available so I do not understand how 2-1/2" of adjustment is accomplished. I only ask as I will be installing an HD-7W on a sloped floor with 1-1/2 to 2" difference.

mustang.connection · Apr 15, 2015

I am in same position as Codybear. I live here in Illinois and I have a 2 1/2" slope. I am looking to install a Bendpak HD-9 within the next 3 weeks. Can I adjust the lift cables or will I need to shim?

Slowbra · Apr 15, 2015

I have a Bendpack HD-9XW on a floor with about a 2.5"-3" slope. Used the steps above to make it work without much work.

Oldb · Apr 17, 2015

I installed a four post in a horsebarn I converted to a shop. The floor had a sewer grade which amounted to around 3" of slope under the span of the lift. Since the floor was thin I cut the concrete, and poured 24" square columns set to level. Welded up a cage in the holes with two I beams on the top, poured the concrete. Welded 3/8 plate to the I beams then welded the posts to the plates, this worked great as I was able to get it exactly square. Only down side is the high side is the drive on side and need extended ramps to get low vehicles on it.

Codybear · May 14, 2015

Now that my lift arrived yesterday and I'm starting the install, I'm going to answer my own question. 2.5" adjustment is not possible without blocking (see below). 1.5" is probably the max I would go which works for me as my floor is 1.25" between the lowest and highest posts. Also, I put the ladder that had the longest length to the first hole in the lowest post and the shortest length in the highest post. By measuring the ladders before installation, I gained about 3/16" for the lowest corner.

The adjustment limitation is that the plastic slides are 2" thick and the lower set is about 1/8" off the base when the crossbar is all the way down. This means the ladder can be raised about about 2.125" off the base before the ladder comes out of the lower plastic slide which would be a disaster if it ever does. I think I would want a minimum of 1/2" of the ladder inserted into the lower slide, which means you can raise the ladder 1.625 inches off the base. So ignoring the instructions, I'd set the highest post's ladder 1/8" off the base (can never be touching the base). Raising the lowest post's ladder 1.625" gives a 1.5" difference between the highest and lowest posts.

If you want more, without modifying the base thickness or the cement, you would have to put a block under the low side crossbeam to prevent it from going all the way down to prevent the lower plastic slide from going below the bottom of the ladder. This is not ideal for low clearance cars.

Bendpak could add more flexibility by raising the lower slide a bit or ideally using a thicker lower slide. They should make it at least 4" thick (or double 2") which would give 2.5" adjustment with a 1" overlap on the ladder and the highest post ladder 1/2" above the base. Maybe ask Jeff for a custom crossbar (you only need to do the low side crossbar).

workhurts · May 14, 2015

Cody is definitely on the correct track. I ended up putting a piece of wood under the crossbeam as I didn't have enough adjustment to deal with the slope. Not ideal on low clearance cars but that can be dealt with easily with scraps of wood.

These lifts are definitely not very adjustable.

Measuring the ladders prior to install is very smart, I think. Also note that the cables from lift to lift are also going to be slightly different effecting adjust-ability. BendPak and others could really make them significantly more adjustable just by adjusting how they do the threads/bullets at the end of the cables.

Codybear · May 14, 2015

workhurts said:
Measuring the ladders prior to install is very smart, I think.

Now that I have crossbeams hoisted and because I didn't use a tape measure originally and just eyeballed them aligned side by side, I see that I only gained 1/8". But if I had randomly placed them and it was reversed, I could have lost 1/8" which would have made the lowest post's ladder 1/4" higher, relatively.

Even if the issue was not about the plastic slide, you will still have to deal with the threaded rod welded at the top and that will definitely limit you to no more than 2.5 inches of adjustment, possibly less.

TS53chey · Oct 10, 2019

Dakota,

How did you adjust the front ladder locks another 3"? Did you get the 3” by adjusting the cables or the locks? My ladder locks don’t start locking until 20” above the floor. I also have 6” of slope in my garage and want to set up my lift similar to yours. Thanks for your help.

Relax · Oct 11, 2019

Once you get the ladders sorted, your next challenge will be the cables. My cables were still too long on one end when the nut was bottomed out on top of the post cap, so I stacked flat washers with an ID large enough for the cable to ride up above the post cap and inside the washers, and was able to take up enough "slack" to get the runways closer to level while between locks.

RubiconJK01 · Jul 29, 2020

Hi All...

I've been following this thread for a while and read it over a few times to help decide on my leveling issues with my 4 post Advantage XLT. I have 3.5" inch difference in my floor between rear and front of lift and was told by the installer and by the mfg that this is just fine (although on the moderate side of slopes). Lift is not bolted down and mfg says it's design is better this way for their lift and should float; although they do provide holes in the base plate if you choose to do so against their recommendation. As installed two of the posts closest to the center of the 2 bay garage are leaning forward; front post more so then the rear. I attribute this to the sloped floor and how the posts are self leveling and floating due to them not being bolted down.

For my own reasons I decided to go with a leveling approach for the front two posts to cancel some of the difference and used Load Bearing Pads used in bridges to raise the front 2.5 inches, leaving me with only 1 inch of difference between front and rear posts. I glued the pads as they came in 1" increments and .5" for shipping to be reasonable. I then glued the top pad to the bottom of base plate. I did not glue to concrete floor to aid in float as the mfg recommends; although there is probably almost no float due to the rubber limiting that "scoot" that might have otherwise occurred.

This worked out great as now the runways are level. However my locks are slightly off between front and rear but Im more happy that the runaways are level so I am leaving it as is. I believe the level I recorded was when in operation but I have to double check that as I doubt they can be level on locks if the front posts are still off by 1 inch.

The issue I do have is I need to somehow compensate for the now 8 inch height to the top of the runway on driving on the lift. The 36" aluminum ramps are not long enough and create clearance issues for my car. Looking for suggestions on how to fix this issue.

If I use the original ramps with some sort of adjoining helper ramps, I need to support under those existing ramps with blocking.

If I use a new ramp altogether it have to be long enough to accommodate the 8" height and low approach angle for my car.

I have looked at all the Race Ramps offerings and nothing seems like it will be perfect but maybe the following will work.
MULTI-PURPOSE SHOP RAMPS - 7 DEGREE APPROACH ANGLE
4 inches high at top section which I can lay my existing ramps onto.

Not sure if any of their other offerings will help any better.

Then there is the idea of something made from wood to accommodate the difference with the ramps.

Thanks in advance!!!
J

boatshoes · Jul 29, 2020

^^^ I think you're right on the money with the race ramps, and won't need the blocking because the race ramps have the space designed in. Based on the pictures it seems like that's exactly what they were designed for.

Garage2Narrow · Feb 24, 2021

I've had a BendPak HD-7W for a few years and want to bolt it to the floor now. Over the length of the lift, I have a drop of about 1.5".

I called BendPak and they said the shims they could sell me are approximately $1, and would provide 1/2" lift. If I wanted to shim more than that, the manual says you can shim up to two inches with "shim plates". I asked BendPak about that and they said that's the same as entire post base-plate, they cost $106 and are currently special order and will take 90 days to come in. He also told me they are 1mm think which is obviously wrong, they are about 1/4" think. So to shim two posts 1.5" this way I'd need 12 plates, for $1200? That seems insane.

I had this conversation today. Short of bringing the plate pattern to a welding shop to see what they can do, what are my options? I'm thinking of shimming the lower posts .5" - 1", then using the ladders to adjust the remaining .5-1".

RubiconJK01 · Feb 24, 2021

Garage2Narrow said:
I've had a BendPak HD-7W for a few years and want to bolt it to the floor now. Over the length of the lift, I have a drop of about 1.5".

I called BendPak and they said the shims they could sell me are approximately $1, and would provide 1/2" lift. If I wanted to shim more than that, the manual says you can shim up to two inches with "shim plates". I asked BendPak about that and they said that's the same as entire post base-plate, they cost $106 and are currently special order and will take 90 days to come in. He also told me they are 1mm think which is obviously wrong, they are about 1/4" think. So to shim two posts 1.5" this way I'd need 12 plates, for $1200? That seems insane.

I had this conversation today. Short of bringing the plate pattern to a welding shop to see what they can do, what are my options? I'm thinking of shimming the lower posts .5" - 1", then using the ladders to adjust the remaining .5-1".

https://vibrasystems.com/load-bearing-pad.html

These are what I used. In the end for raising my lift 2.5 inches I think I paid around 375.00 delivered. These are used in between the concrete and bridge trusses for shifting of weight so as not to crack the concrete structures. I felt this product was way better than the recommended horse stall mats or gym mats you can find just about anywhere. I glued them together to build up my height and then glued them to the base plate of the two front posts.

I used a combination of ...
BPXP-1-12-12 x 4 pcs
and
BPXP-.50-12-12 x 2 pcs

Garage2Narrow · Feb 24, 2021

https://vibrasystems.com/load-bearing-pad.html

These are what I used. In the end for raising my lift 2.5 inches I think I paid around 375.00 delivered.

Thanks, that's helpful. If I understand correctly, now the front crossbar and ramps will be ~1.5" off the front of the concrete - do you need to support the crossbar when that happens, and what did you do about ramps? Can you post a photo to help visualize?

Thanks!

RubiconJK01 · Feb 24, 2021

Garage2Narrow said:
Thanks, that's helpful. If I understand correctly, now the front crossbar and ramps will be ~1.5" off the front of the concrete - do you need to support the crossbar when that happens, and what did you do about ramps? Can you post a photo to help visualize?

Thanks!

Yes so the front crossbar and runways will obviously be that much higher based on what you did for adding height to the front two posts, or rear posts if its sloping that direction. Here in new england US, the garages are sloped to help with snow melt to the front of garage. So I raised my posts closest to garage door.

For ramps, the stock ramps will need to be supported by either the same product I mentioned above or something similar, maybe those more common horse \ gym mats or wood etc. I initially did the wood route since I had scraps. I was thinking of buying more of those load bearing pads but didn't want to spend the additional costs. Also I had a bigger issue where even if I supported my original ramps with any of the above options I was at too steep of a height for my lower clearance cars so I had to find longer ramps.

Now the issue for me at least, the longer ramps from my lift, Advantage Lift, would still be too short for my cars, so I went to the route of buying trailer ramps made from aluminum. in 7ft lengths so I have plenty of clearance and gradual slope onto the runways. If I just loaded SUVs on it then I would have never needed anything but the original ramps and some support as I mentioned.

Garage2Narrow · Feb 24, 2021

Makes sense, that's what I was expecting. I'm in New England as well, so its the same situation for me as well.

RubiconJK01 · Feb 24, 2021

Garage2Narrow said:
Makes sense, that's what I was expecting. I'm in New England as well, so its the same situation for me as well.

Here is some pics...

RubiconJK01 · Feb 24, 2021

Garage2Narrow said:
Makes sense, that's what I was expecting. I'm in New England as well, so its the same situation for me as well.

I got the 12x12 sizes from that site. If I were to get the next size up, which I originally wanted for a bit more coverage under the base plate, the shipping was ridiculously more since it was way more weight. So I opted to just match the base plate. However in doing so, if I ever wanted to bolt to my floor I am at the 4 corners of the holes I need to drill in the rubber, which might be an issue?, not sure. In any case I am not planning to bolt it as my mfg of lift says it was designed to be a floating lift and as such may move slightly if necessary. However I think with my rubber under there, its not moving much at all.

When I raise the car up you can see the rubber compressing which I believe is fine and vise versa when you bring the car all the way down the front comes up a hair since the rears are baring some weight. Either up or down those pads are hard as hell and seem like they are way stronger than they need to be.

logical · Feb 24, 2021

Composite fiberglass reinforced shims, trimmed steel ramps, Race Ramps trailer ramps

Sent from my SM-G960U using Tapatalk

4 post lift on a sloped garage floor...

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