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Bendpak 4-Post Stability

MAYOR28

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Brand new 4-Post owner here. I have some questions about the stability of the lifts, with and without load.

I know that this question has been asked and asked again, and yes, I used the Search tool. I have discovered that about 60%-70% never bolt down their 4-Post lifts. However, I am not very happy with the wobbliness of my lift (even with a car on it).

At full extension (without a car) the top of the columns can sway about +/- 7". With a car this is reduces to +/- 4". :shocking::wtf::shocking:

My next idea, before renting a rotary hammer, is to take the plywood out from under the posts to see if that is affecting the stability. ( I did this for set up purposes, so I wouldn't scratch up the floor.)

I am a little worried that bolting the lift down will not solve all of these issues, as there seems to be a massive amount of play between the crossbeams and the inner columns (the guide-blocks look like they should be shimmed?).

Has anyone else experienced this?


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LX-Markham

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Mine sways, but not THAT much. Maybe an 1"? It feels like it's swaying a lot, but if I had to measure it I know it's not as much as it feels. (mine is bolted down)

7" seems like something is way out of whack.
 

Viper98912

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GA
I don't have a bendpak, but do have a 4 post. I share your concerns, and while I don't try to REALLY rock it, when I do rock it to check, at max it's only like 1". 4" is a lot...
 
OP
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MAYOR28

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Mine sways, but not THAT much. Maybe an 1"? It feels like it's swaying a lot, but if I had to measure it I know it's not as much as it feels. (mine is bolted down)

7" seems like something is way out of whack.

Yours sways about an inch when bolted down? That seems much more reasonable.

I am tempted to post a video so people can see the sway, Bendpak wasn't all that helpful, they just told me to make sure I did the leveling procedure......
 

pbon

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My HD-9XW is not bolted down and is on a wood floor, not concrete. It swayed noticeably when not loaded, but that was before I leveled it so the locks engage at the same time. I do have 2 bridge jacks and they may add to the stability by adding weight and tying the runners together in 2 more places. With a car on it, I have zero concerns about the stability.
 

akdiesel

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Wasilla, AK
I too have the HD-9XW not bolted down for the reason is I relocate mine once in a while. I actually have mine on 6” risers to clear a skid steer parted under it. We also had a large earthquake back in November with a small car stored in the full height position and the bottom pads did not shift on the floor. I am sure the car and the runways were moving around but I was not in there to witness it.
 

SJW

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Thousand Oaks, CA
Did you ask the installer to come back out and check to see why there's so much swaying? That sounds like a lot for a 4-post lift.
 

pbon

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I am going to guess the OP put the lift together himself and gas not fully installed it by leveling it as set forth in the instructions do all the locks engage at the same time.
 
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MAYOR28

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I am going to guess the OP put the lift together himself and gas not fully installed it by leveling it as set forth in the instructions do all the locks engage at the same time.
Yes, I did it myself. And yes, I leveled per the instructions, I used a laser level to get the runway corners all within about 1/16" of each other.

However, I know one cable stretched a little on the first few lifts as the one lock does not click at the same time now, but that is the cable, not the ladder.




...
 

pbon

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Make sure the ladders are level as well as the corners of the lift since engaging the locks seem to add stability.
 
OP
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MAYOR28

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Make sure the ladders are level as well as the corners of the lift since engaging the locks seem to add stability.

The ladders are level, all the locks clicked in unison when the lift was empty, therefore, I believe I need to adjust the cable a few more times. Right?
 

SJW

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I think a video of the sway might help us understand better.

Also, you mentioned in your first post that there was a lot of play between the crossbeams and the inner columns; could you get some video of where they come together?

Finally, what lift model do you have?
 
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MAYOR28

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I think a video of the sway might help us understand better.

Also, you mentioned in your first post that there was a lot of play between the crossbeams and the inner columns; could you get some video of where they come together?

Finally, what lift model do you have?

I talked with Bendpak this morning. I am going to send them a video, and if I can, I will upload it here.

Lift is an HD9XW. Normal width, extra tall.

..
 

NitroShark

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Greenville, SC
Cables are diffidently not adjusted correctly per your Video. You should hear all safely ladders "click" in unison.

Adjust accordingly and report back!

..and get rid of the Plywood.
 
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MAYOR28

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Cables are diffidently not adjusted correctly per your Video. You should hear all safely ladders "click" in unison.

Adjust accordingly and report back!

..and get rid of the Plywood.
Will do.

Should I adjust the cable again under some load? Or completely unloaded?




...
 
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MAYOR28

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Always fully loaded.

Thanks! I will give it a shot tonight.

But I still don't really understand if that will eliminate the wobble. Since the lift is not resting on the cables when it is on the locks, how will this stop the instability?
 

SJW

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Just my 2 cents.

I don't think you need to adjust the cables. They are hitting the locks pretty close to the same time, from what I can hear in the video.

I would focus more on the floor. Remove the plywood and check to see if the floor is completely flat or not. The third video appears to me to show the plywood rocking on the floor.
 

66Caprice

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Stanwood, Washington
If you want it to be more stable then you need to bolt it down. Mine is not bolted down and yes it does wobble too. Your towers are exaggerating the wobble partly because they are extra tall. Get the plywood out of there. If you need something to help lift up an end to aid in leveling then use some steel. Hell when I have my cars fully lifted if I need to get into the car I climb a ladder and crawl right up on the runners and walk them.
 

firebirdparts

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There's no reason that any adjustment or leveling or whatever would affect the wobble. It wobbles because the legs move up and down, by design, and there's slop in there plus the engagement of the 'table' is not very tall. There is just not a lot of rigidity there, by design.

If you bolt it down it would make a huge difference.
 
OP
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MAYOR28

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Thank you all!

I have determined that I need to remove the plywood (which I have been struggling to figure out how to do), then move the lift a little bit further into the bay, then try everything out again.

I think I will bolt it down (it will just cost me $30 to rent + 1/2 day of drilling, so what is the loss?) once it is in its final resting place.
 

DPelletier

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Before you bolt it down, make sure the floor is level and shim if necessary.

Dave
 
OP
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MAYOR28

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I was able to move the lift this weekend (hopefully to its final resting place), it is much more stable off of the plywood, but not completely stable. I believe that the column baseplates are not flat, but bowed under the weld areas. That is creating the instability.

I guess I will be bolting it down. I am rather disappointed to say the least.....




Another question though:


Anyone have issues with the RJ45 reaching frame rails/unibody points? I was not able to reach the jack points on a 2009 Honda Civic with the jack (car too wide). This was also very disappointing. Anyone else have troubles like that? Am I doing wrong?

...
 

pbon

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May 14, 2017
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Yes, that is a problem with most cars. I don’t think they are intended to reach the rocker label factory jack points that exist on many imports. Rather they reach frame rails or subframes. I often ******** my front subframe, using wood on top of the jack as a pad.

I did recently buy extensions for the rj-45 arms. A welder could probably make them. They slide onto the existing arms but you cannot leave them in place full time because they would not retract into the jack and your wheels would hit them when you drove onto the runners. The ones I bought were about $300 for a pair.

http://www.sviinternational.com/

They probably reduce the jack capacity but I don’t lift 4500 lbs per jack with my 3000-4000 lb cars. They are 13” extensions but I think 8” would have been all I would ever need and 4” would have met my current needs.
 

ripnesscobra

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Aug 22, 2016
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MA
pbon, can you give us some more information about the 13” extension kit you bought for the Bendpak RJ45 from SVI?

I looked on their website but was only able to find a 10” extension kit for the Challenger RJ4.5 rolling jack (part number BH-7231-46).

Do they sell 4”, 8” and 13” extension kits for the Bendpak RJ45 or just the 13” like you have?

Is the 13” extension kit compatible with both the older Bendpak RJ45 and the newer Bendpak RJ4500?

Is the 13” the total extension (6.5” per side)?

Thank you.
 

pbon

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I looked up the details I have. SVI PN BH-7474-81 $302.50. It is a 9” extension per side, not 13” as I first wrote, but maybe the part is 13” long. I believe they can do different lengths. The 9” is more than I need for my BMW E36, E90 and E60 but maybe I will have a wider car in the future. I bought the old style rj-45 that Bendpak will still make for lower profile cars. I assume but do not know that these extensions will fit the new certified version as well, which I think has a slightly bigger frame but not thicker arms. You would have to double check.
 
OP
M

MAYOR28

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I guess I will have to look into those options. Seems rather crappy for a $1600 scissor jack......

At the very least I am going to buy some rubber pads (hockey pucks?) for on top of the jack's center cross-member so I don't have to use wood anymore.
 

pbon

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I would stick with wood unless the pads are low profile. I don’t think many of these scissor jacks are wide but there may be one model from another company that makes a jack that fits and is slightly wider. The arms have to retract into the body.
 
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