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Impact of falling off a jack

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Old 11-04-2007, 08:20 PM
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jlb532
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Default Impact of falling off a jack

Swapping my winter wheels on with my new hydraulic jack...didn't realize the sensitivity of the release valve.

Started with the front passenger tire, swapped the winter wheel...went to lower and turned the release valve of the jack too quickly. Car came crashing down.

I had the wheel on, and I figure the car does have springs up there...but nonetheless it sounded pretty loud.

I didn't think much of it, and went on to replace the other 3 wheels...CAREFULLY releasing the jack each time.

After finishing, I took the car out for a spin and find it's now pulling to the right.

My question to the board is: Could such an impact (dropping the car from the height of a jack (wheel an inch off the ground)) be enough to throw off the alignment, or even worse to have bent a control arm or spring? My concern is that the impact would be much more than simply hitting a pothole, as while the wheel was only 1" up, as you know-the frame of the car needs to be elevated about 5 inches more than that (since the wheels droop when the car lifts).

I tried a different tire arrangement too and still get the same pull, so I have ruled out a "bad" tire.

Car did not pull before this, with the summer tires. So I either did something to it, or it's a property of the narrower winter tires.

What do you think?
Old 11-04-2007, 08:34 PM
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jumper5836
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I doubt dropping to quickly from the jack would cause a problem, unless the jack slipped and you fell on it with something other then the jack point.

I know when I put my narrow tires on, I feel like it is loose in the back, mucg easier to get the tail out. But it feels a bit more stable in the roads with ruts.
It doesn't pull to any side though, not unless the road causes it.
Old 11-04-2007, 08:35 PM
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Riad
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I'm guessing you knocked the car out of alignment... not hard to do.
Old 11-04-2007, 08:37 PM
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ArneeA
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If you think about it, it's like catching some air and dropping that weight of the car on the same side. That could ruin the alignment. Check your tie rods if they were bent.
Old 11-04-2007, 11:12 PM
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Tool Pants
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Check it with your summer tires back on.
Old 11-05-2007, 01:01 AM
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Patrick
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If dropping from 1" on the jack would knock the car out of alignment, mine would never be aligned. Hell, hitting the gators at the track is more traumatic. I agree with Jeff's suggestion.
Old 11-05-2007, 02:57 AM
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Tippy
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I highly doubt that would knock the alignment out.
Old 11-05-2007, 09:03 AM
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drmarkp
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Mmm - but he had the wheel on so where's the solid to solid contact? I'm with Patrick.
Old 11-05-2007, 09:10 AM
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LVDell
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interpreted now as you say mark and I see that he in fact had the wheel bolted back on. initially it can be interpreted as he was solid to solid. obviously not the case. Concur as well.

dropping the car off the jack though isn't going to cause an alignment problem. There is something else at play here. Tire pressure, properly threaded and torqued bolts, etc.
Old 11-05-2007, 09:22 AM
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Barn996
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I just don't think you'd knock out alignment that easy. Driving on any road surface today would create more of an alignment issue than your description of falling off a jack. Your suspension would soak it up IMO.
Old 11-05-2007, 10:05 AM
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jlb532
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Thanks for the input guys, it's very puzzling. My initial reaction was that it shouldn't be a big deal, as roads present potholes, railroad tracks, etc on a daily basis. On the other hand, this "type" of impact isn't quite the norm...as while the wheel (with tire on) may have only been an inch up...the FRAME must be elevated 5-6 inches in order to get the wheel to clear the ground.

So it's more of an impact than just a "wheel bounce"...how much more is the question.

I know the only way I'll be able to tell for sure is go swap all the summer wheels back on...but with my spacers and all that crap, wheel changes are not all that quick...and I'm tempted to just wait it out until spring.

I can live with this pull for now IF I know it's only attributed to these winter tires...but given that my having swapped the winter tires arrangement (front to back-they're directional) did not cure the problem...I'm a little concerned.

Uggghhh.
Old 11-05-2007, 10:43 AM
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pl
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i don't think there's much demage if the wheel is already bolted on.
but it doesn't hurt to check the alignment, after all, u swapped wheels.
on the side note, i found the jake comes with the car is very easy to use, when i swapping my winter tires last weekend.
Old 11-05-2007, 09:32 PM
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C4CRNA
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Was the wheel fully tightened up before the fall? I would try retorking that wheel. It could be slightly off the bolt.
Old 11-05-2007, 11:17 PM
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nycebo
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Take it for an alignment if you feel that it's not driving true. Generally, I go in for one almost every year what with the bumpy northeastern roads.
Old 11-06-2007, 10:58 AM
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jlb532
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Wheel was on, but I didn't torque to spec until after it was lowered. I hesitate to take for an alignment now, because the summer wheels were very true...and I'd rather keep them that way.

Again, I can live with this pull...for the winter season...as long as I can be fairly confident that it's only attributed to the winter rubber/winter setup, and not a bent component resulting from that drop from the jack.

I guess I won't know for certain until the summer wheels are back on, but I was just trying gather thoughts as to whether such a drop probably did something, or whether what I'm observing is more likely due to the winter tires.


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