Supporting trailer for axle swap

[69bullet]

My new single axle arrived and im gearing up for the swap out.

The one thing other posts dont show is how you supported the trailer safely to remove the axle and work under the trailer.

[overlander63]

A jackstand under the frame rail just behind the axle.

[mimiandrews]

What Overlander63 said, only I used several jack stands--two located as he said, two more under the frame rails near the rear, two more under the A-frame at the front.

I was working alone, and I'm getting chicken in my old age.

[gdanderson]

I used four concrete blocks at four locations about 1/3 the distance from the front and the back of the trailer. I placed two blocks on the floor centered under the rail with two more blocks stacked on top of the two on the floor in the opposite direction. Then I placed a wood 4" X 4" on top of the four stacked blocks that spread out the load across the concrete blocks. I have jack stands but didn't like the look of that setup. Not enough surface contact area at the trailer for me. I put the block system at the locations to balance the weight of the trailer evenly, 1/3, 1/3, 1/3. Also it kept the blocking away from the work area. The blocks are inexpensive at $0.99/ea., so for $16 and time I had a very stable way to work under the trailer. After I finished I put the blocks out at the street with a "free" sign on then and they were gone in an hour. Pictures are of the axle replacement and not specificity of the blocking system.

Greg Anderson
Wisconsin

[cwf]

Hee is a method used in many construction sites !

Source:
http://www.cert-la.com/cribbing.pdf

Cribbing is essential in many extrication operations. Its most common use is to stabilize objects. Wood selected for cribbing should be solid, straight and free of major flaws such as large knots or splits. Cribbing surfaces should be
free of any paint or finish because this can make the wood slippery, especially when it is wet. Cribbing can be made out of pieces of timber found in the debris and cut to size. Pieces of 2X2 (5 cm X 5 cm) and 4X4 (10 cm X 10 cm) as well as wedges cut in this size timber are very useful.
Cribbing involves multiple pieces of wood laid on the side and crossed. It spreads the load well and has many load transfer surfaces. It also has lateral stability depending on the ratio of width to height. The height should not be more than three times the width. (Note: pieces should not be more than two feet (60 cm) long.)
The overhang at corners should be no less than 4 inches.
4X4 crib capacity = 24,000 lb. (10,886 kg).
6X6 crib capacity = 60,000 lb. (27,215.5 kg).
Note: using 3 pieces per layer as in 3X3 (7.5 cm X 7.5 cm) crosstie will double the capacity.

[Sodbust]

FYI,,, and a warning.. Concrete blocks can shatter under load. Had it happen with me on a non A$ project.. Using wood boards across the top and bottoms help but if the stress is uneven they can fail..

Hate to hear your A$ did you in..

Sodbust

[69bullet]

Thank you everyone. I do have the auto safety stands, and i know that they are there only for additional safety. I know even though the stands can hold the weight, it only takes a certain shift and large object falls off of the stands.

I already had in my mind the blocks and 2x6's or 4x4s across them, You confirmed this would be the wiser way to support the vehicle. Off to home depot for a parts run.

Pictures to follow.

[kscherzi]

I echo the safety concerns over concrete blocks. They are brittle and prone to sudden shatter. Concrete blocks are meant to be in conjunction with steel rebar and filed with concrete. If you must, do not lay them flat but holes up, and only place them on a solid surface, not gravel or dirt. I'd also not recommended climbing under the trailer if only supported by concrete blocks.

[NavyCorpsman]

What do you call Batman and Robin after they get crushed?

Flatman and Ribbon.

[PaulnGina]

Originally Posted by cwf

Hee is a method used in many construction sites !

Source:
http://www.cert-la.com/cribbing.pdf

Cribbing is essential in many extrication operations. Its most common use is to stabilize objects. Wood selected for cribbing should be solid, straight and free of major flaws such as large knots or splits. Cribbing surfaces should be
free of any paint or finish because this can make the wood slippery, especially when it is wet. Cribbing can be made out of pieces of timber found in the debris and cut to size. Pieces of 2X2 (5 cm X 5 cm) and 4X4 (10 cm X 10 cm) as well as wedges cut in this size timber are very useful.
Cribbing involves multiple pieces of wood laid on the side and crossed. It spreads the load well and has many load transfer surfaces. It also has lateral stability depending on the ratio of width to height. The height should not be more than three times the width. (Note: pieces should not be more than two feet (60 cm) long.)
The overhang at corners should be no less than 4 inches.
4X4 crib capacity = 24,000 lb. (10,886 kg).
6X6 crib capacity = 60,000 lb. (27,215.5 kg).
Note: using 3 pieces per layer as in 3X3 (7.5 cm X 7.5 cm) crosstie will double the capacity.

I have used this exact cribbing method to support our 1987 Avion 34W. It is very stable and made me feel very comfortable when I needed to crawl under the trailer.

No concrete blocks!!!!

[Action]

I don't have issues with masonary to support a heavy object. I just won't go under same object if supported by masonary. And don't support objects I care about with masonary.

>>>>>>>>>>>>>>>Action

[NevadaGeo]

Originally Posted by Action

I don't have issues with masonary to support a heavy object. I just won't go under same object if supported by masonary. And don't support objects I care about with masonary.

>>>>>>>>>>>>>>>Action

Think of the CMU ( concrete masonry unit) as a weak, brittle shell to put concrete into. If you strike an empty block shell with a hammer, it will shatter. The shell is the weakest part of a masonry building, the strength comes from the concrete grout that is placed inside the masonry wall. That will be heavy, but fill the CMU with concrete, then it will be much safer for a support block. Heavy, but safer. Make the concrete nice and wet, put it in the block, rod or stir the concrete a couple times while the block is sucking the water out of the concrete. That also sucks some of the cement into the block, making the concrete bond to the block. When grouting a masonry wall I have to make the crew vibrate the concrete twice to make the solid bond, per code. (Don't feel bad, I've had Architects that didn't know the empty block is worthless for strength too.)

[cwf]

I had solid CONCRETE blocks that worked pretty well as 'furniture' when I was a batchelor.. lo many years forgotten... till this post. They were really heavy, too. But I NEVER used them to support anything I would crawl under.

We use the 'cinder blocks' customarily referred to as 'concrete/masonry' blocks for buildings.. you carefully drop them over rebar then pour concrete inside.. to fill it up.. That is fairly strong...but, I have seen the result of putting those in the way of hurricanes... doesn't work too good.