Jack Stand Safety
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Joined: Aug 2013
Posts: 97
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From: Indiana
Jack Stand Safety
Doing a clutch repair.
I'm putting my C4 tires up on 16x12x8 cement blocks. Safe or no?
Jack stands alone feel dangerous... even tho I have 6 ton jack stands. Somehow the wheels touching solid surface helps me feel safer underneath that car. Plus the jack locations seem really close to the center of weight balance to trust them alone.
thoughts?
I'm putting my C4 tires up on 16x12x8 cement blocks. Safe or no?
Jack stands alone feel dangerous... even tho I have 6 ton jack stands. Somehow the wheels touching solid surface helps me feel safer underneath that car. Plus the jack locations seem really close to the center of weight balance to trust them alone.
thoughts?
Safety Car
Joined: Sep 2010
Posts: 3,752
Likes: 190
From: Indiana PA
Extra insurance never hurts, however, if the car is properly supported by the jack stands in the correct locations. The car isn't going anywhere.
DO NOT EVER TRUST CEMENT BLOCKS TO HOLD THE WEIGHT OF A CAR.
WOOD ONLY!!
If you do happen to use cement block as "supplemental" support, make sure they are on end (tire on the holes, NOT the flat) the strength of the block is on the hole side not the flat side. They are for walls...
DO NOT EVER TRUST CEMENT BLOCKS TO HOLD THE WEIGHT OF A CAR.
WOOD ONLY!!
If you do happen to use cement block as "supplemental" support, make sure they are on end (tire on the holes, NOT the flat) the strength of the block is on the hole side not the flat side. They are for walls...
Burning Brakes
Joined: May 2010
Posts: 941
Likes: 10
Having been a professional Fire Chief for 32 years, now retired, I have see two people crushed dead using Jack Stands that failed. I will never use Jack Stands. I use 6x6" wood cribbing, cross stacked. Its safe, its not going anywhere. Never use concrete blocks as they two can fail.
8Valve
8Valve
Safety Car
Joined: Aug 2009
Posts: 3,751
Likes: 276
From: Melbourne, Victoria, Australia
Do not trust jack stands especially the ones with the upright welded on a steel plate, how good can those Chineese weld 
Cement can break easilly so i would recommend a large wood block instead of concrete.
I have pulled a car from jack stands they can tip over quite easilly, I always put one of my wheels under the car to be sure.
Buy the jack stands with side angle brackets for extra support and tipping resistance. 
Cement can break easilly so i would recommend a large wood block instead of concrete.
I have pulled a car from jack stands they can tip over quite easilly, I always put one of my wheels under the car to be sure.
Buy the jack stands with side angle brackets for extra support and tipping resistance.
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Brett Foote
Race Director
Joined: Apr 2002
Posts: 10,036
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From: Anaheim CA
I had a jack stand break. Spot welds came apart. Fortunately it was on an asphalt driveway and the legs dug into the asphalt and didn't split completely apart. I borrowed the set, so it wasn't me who picked the junk pieces.
I have four 6"x6"x10" pieces of lumber that I have used for many years. In retrospect I should have made them about 3" longer.
I have four 6"x6"x10" pieces of lumber that I have used for many years. In retrospect I should have made them about 3" longer.
Team Owner
Joined: Aug 2008
Posts: 32,992
Likes: 6,523
From: Rochester NY
St. Jude Donor '09 thru '26
I would not use cement blocks under any circumstances
I always use two separate systems. Usually it's jack stands, and wood. I have some oak blocking we used to use for rerailing freight cars, 4" x 8" x30". Alternately, I have a whole bunch of 4 x 4 wood in 1 foot lengths. I'll put 3 side by side, then 3 more on top going 90 degrees to the first, then alternate each layer until it's high enough.
Bottom line is don't rely on just one type. Jack stands are fine if you have a back-up system which will take over. And before getting under, shove the car back and forth in each direction to be sure it's steady on whatever you use.
I have known SEVERAL people who either were killed themself, or lost relatives, by vehicles falling. I'm not normally "fussy" but this is one area where I believe in being obsessive.
"OVERKILL IS BETTER THAN BEING 'UNDERKILL' "
I always use two separate systems. Usually it's jack stands, and wood. I have some oak blocking we used to use for rerailing freight cars, 4" x 8" x30". Alternately, I have a whole bunch of 4 x 4 wood in 1 foot lengths. I'll put 3 side by side, then 3 more on top going 90 degrees to the first, then alternate each layer until it's high enough.
Bottom line is don't rely on just one type. Jack stands are fine if you have a back-up system which will take over. And before getting under, shove the car back and forth in each direction to be sure it's steady on whatever you use.
I have known SEVERAL people who either were killed themself, or lost relatives, by vehicles falling. I'm not normally "fussy" but this is one area where I believe in being obsessive.
"OVERKILL IS BETTER THAN BEING 'UNDERKILL' "
Tech Contributor
Joined: Aug 2006
Posts: 9,933
Likes: 103
From: Peoria Arizona.. Resident Gold Cylon
In short you have a death wish but you are wise to ask the question. Blocks can fracture and break. Heavy blocks of wood, Jack stands and dont forget the wheel chock. Sometime if space available I leave the floor jack as support as well as yet another back up. Never use concrete blocks.
Last edited by Goldcylon; Aug 29, 2013 at 09:09 AM.
Intermediate
Joined: May 2013
Posts: 30
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From: Melbourne Victoria
In short you have a death wish but you are wise to ask the question. Blocks can fracture and break. Heavy blocks of wood, Jack stands and dont forget the wheel chock. Sometime if space avaiable I leave the floor jack as support as well as yet another back up. Never use concrete blocks.
Tech Contributor
Joined: Aug 2006
Posts: 9,933
Likes: 103
From: Peoria Arizona.. Resident Gold Cylon
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Seriously? A "death wish"?? Come on now...I think that we're being a little dramatic here. Let's not be alarmists, shall we? 
The OP is using jack stands...which if they are of any kind of decent quality and positioned correctly, is very, VERY safe. In addition to the jack stands, he has placed concrete blocks (in their strong direction) under the tires as a "back up". I really don't thing that the OP is seeking death, here.
While I agree with the other posters that it's possible for concrete blocks to fracture and fail, it is not likely and in their capacity as back-ups...incredibly unlikely. Although there are safer "Back-ups", I think that the OP will get through this job alive.
My best practices are:
*Use good stands
*Set the car on them properly
*SHAKE the car aggressively as a test
*Use the wheels as a "back-up"
The OP is using jack stands...which if they are of any kind of decent quality and positioned correctly, is very, VERY safe. In addition to the jack stands, he has placed concrete blocks (in their strong direction) under the tires as a "back up". I really don't thing that the OP is seeking death, here.
While I agree with the other posters that it's possible for concrete blocks to fracture and fail, it is not likely and in their capacity as back-ups...incredibly unlikely. Although there are safer "Back-ups", I think that the OP will get through this job alive.
My best practices are:
*Use good stands
*Set the car on them properly
*SHAKE the car aggressively as a test
*Use the wheels as a "back-up"
Racer
Joined: May 2008
Posts: 430
Likes: 1
From: Austin Texas
Then, you see something like this, and really, really wonder how smart some people are:
http://www.google.com/imgres?sa=X&bi...18&tx=65&ty=84
Jim G
http://www.google.com/imgres?sa=X&bi...18&tx=65&ty=84
Jim G
Melting Slicks
Joined: Feb 2008
Posts: 2,384
Likes: 56
From: West Chester PA
St. Jude Donor '09 thru '25
only time I use jack stands anymore is if I have to pull wheels. Under the car, race ramps.
Tech Contributor
Joined: Aug 2006
Posts: 9,933
Likes: 103
From: Peoria Arizona.. Resident Gold Cylon
Seriously? A "death wish"?? Come on now...I think that we're being a little dramatic here. Let's not be alarmists, shall we?
The OP is using jack stands...which if they are of any kind of decent quality and positioned correctly, is very, VERY safe. In addition to the jack stands, he has placed concrete blocks (in their strong direction) under the tires as a "back up". I really don't thing that the OP is seeking death, here.
While I agree with the other posters that it's possible for concrete blocks to fracture and fail, it is not likely and in their capacity as back-ups...incredibly unlikely. Although there are safer "Back-ups", I think that the OP will get through this job alive.
My best practices are:
*Use good stands
*Set the car on them properly
*SHAKE the car aggressively as a test
*Use the wheels as a "back-up"
The OP is using jack stands...which if they are of any kind of decent quality and positioned correctly, is very, VERY safe. In addition to the jack stands, he has placed concrete blocks (in their strong direction) under the tires as a "back up". I really don't thing that the OP is seeking death, here.
While I agree with the other posters that it's possible for concrete blocks to fracture and fail, it is not likely and in their capacity as back-ups...incredibly unlikely. Although there are safer "Back-ups", I think that the OP will get through this job alive.
My best practices are:
*Use good stands
*Set the car on them properly
*SHAKE the car aggressively as a test
*Use the wheels as a "back-up"
Last edited by Goldcylon; Aug 29, 2013 at 12:29 PM.
Tech Contributor
Joined: Aug 2006
Posts: 9,933
Likes: 103
From: Peoria Arizona.. Resident Gold Cylon
Then, you see something like this, and really, really wonder how smart some people are:
http://www.google.com/imgres?sa=X&bi...18&tx=65&ty=84
Jim G
http://www.google.com/imgres?sa=X&bi...18&tx=65&ty=84
Jim G
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
You see the jack stand tilted over and shifted the weight to the blocks and they exploded, luckly one side held long enough for me to pull him out from under the car. My friend broke his pelvis pretty dramatic No? I suggested wood blocks and Jack stands for that purpose. Insert rolley eyes I guess
The back-ups shouldn't even matter, b/c the car shouldn't leave the stands in the first place. It can happen however (your friend proved that), so a back up isn't bad. Having a less-than-ideal BACK-UP is hardly a "death wish" however, and that was my point. The OP is obviously safety conscious, using two systems to support the car, and asking for opinions too. "Death wish"? No.