Why not jack trailer under the spring plates?

[opnspaces]

For years people have asked where to place the jack in order to jack up a travel trailer. And people always say do not put the jack under the spring pack. This has bothered me for years because it doesn't make sense to me. Now I'm not an engineer by any means. But could somebody please explain why under the spring pack is bad? I mean look at the pictures below. In an under slung axle the entire weight of the trailer looks to be on two very small u-bolts. Am I wrong? It seems that the u-bolts are holding the weight. If the thin u-bolts are holding the weight.and the spring is on a thin perch welded under the axle; How is jacking at that point going to be a problem?


And in a travel trailer with over slung axles putting a block, or even a floor jack under the axle seems like it would be okay. The axle tube is thick enough to hold the trailer in the air with the u-bolts on top. Are we saying the tube is thinner on the opposite side of the axle tube?

[Grit_dog]

Alan_Hepburn wrote:

msmith1.wa wrote:
Dexter recommends trailers not be jacked up by the axle.

I have done it many times and will continue.

Have any of you looked at the jacking instructions for your truck. GM and Ford owner's manuals show placing the provided jack under the axle tube. I didn't check Ram's instructions.

There is a world of difference between the axle tubes on a truck and the axle tube on a trailer...

But they still won’t crush under the static load of being raised off the ground gently.

Just like many mfgs warnings, capacities and required/recommended procedures, they are in place to hopefully stupid proof something and result in less financial loss due to claims and the bad publicity that comes with it even if the individual id10t who is making the claim was in the wrong.
Or in other words, most everything that is sold to the public that has any risk of anything going wrong will come with instructions and caveats to attempt to limit risk and liability by all users, even those who are largely or completely ignorant as to what they are doing.
Has to be dumbed down to the least common denominator on the IQ scale…

[Alan_Hepburn]

msmith1.wa wrote:
Dexter recommends trailers not be jacked up by the axle.

I have done it many times and will continue.

Have any of you looked at the jacking instructions for your truck. GM and Ford owner's manuals show placing the provided jack under the axle tube. I didn't check Ram's instructions.

There is a world of difference between the axle tubes on a truck and the axle tube on a trailer...

[valhalla360]

Chum lee wrote:

Dutch_12078 wrote:

Chum lee wrote:
Ever see leveling Jack's attached to the suspension? That should tell you something.

Chum lee

Leveling jacks would not stabilize the RV if they were attached to the suspension. The RV would bounce and rock the same as it does with no jacks or stabilizers.

Thank you! That is EXACTLY my point which you have somehow missed. When you (or any other human) crawls under an +-18,000 lb. vehicle, . . . it should be stabilized CORRECTLY AND SECURELY. If not, if/when something unexpected happens, . . . . . your body (or parts of it) becomes the stabilizer.

Chum lee

Yeah, it tells you they are bypassing the suspension because the trailer would still bounce around if you attached the to the axles. This has nothing to do with jacking a tire up.

Yes, you should make sure it stable before going under but you have provided no evidence it's better to do that with a very tall (inherently unstable) jack vs down low on the spring perch.

Of course, if we are talking changing the tires, you shouldn't be under the trailer.

[Cummins12V98]

larry barnhart wrote:
I made a trailer aid for our Alfa ideal. Jacked that tire high into the wheel well and the other tire was still on the ground. Chevman

Add a block under it if needed.

[larry_barnhart]

I made a trailer aid for our Alfa ideal. Jacked that tire high into the wheel well and the other tire was still on the ground. Chevman

[msmith1_wa]

Dexter recommends trailers not be jacked up by the axle.

I have done it many times and will continue.

Have any of you looked at the jacking instructions for your truck. GM and Ford owner's manuals show placing the provided jack under the axle tube. I didn't check Ram's instructions.

[nickthehunter]

I have a jack, not sure why I need to "open their eyes to the many benefits of using a TrailerAid Plus"?
My jack seems to work just fine, has many other uses, takes up less space; and is not a one trick pony.

[Cummins12V98]

People need to open their eyes to the many benefits of using a TrailerAid Plus.

[Dutch_12078]

Chum lee wrote:

Dutch_12078 wrote:

Chum lee wrote:
Ever see leveling Jack's attached to the suspension? That should tell you something.

Chum lee

Leveling jacks would not stabilize the RV if they were attached to the suspension. The RV would bounce and rock the same as it does with no jacks or stabilizers.

Thank you! That is EXACTLY my point which you have somehow missed. When you (or any other human) crawls under an +-18,000 lb. vehicle, . . . it should be stabilized CORRECTLY AND SECURELY. If not, if/when something unexpected happens, . . . . . your body (or parts of it) becomes the stabilizer.

Chum lee

If you need to crawl under the RV, the unit should be stabilized with jack stands or cribbing regardless of the jacking point. Depending on a jack alone is neither CORRECT OR SECURE.

[Chum_lee]

Dutch_12078 wrote:

Chum lee wrote:
Ever see leveling Jack's attached to the suspension? That should tell you something.

Chum lee

Leveling jacks would not stabilize the RV if they were attached to the suspension. The RV would bounce and rock the same as it does with no jacks or stabilizers.

Thank you! That is EXACTLY my point which you have somehow missed. When you (or any other human) crawls under an +-18,000 lb. vehicle, . . . it should be stabilized CORRECTLY AND SECURELY. If not, if/when something unexpected happens, . . . . . your body (or parts of it) becomes the stabilizer.

Chum lee

[Grit_dog]

I predict this thread will reach at least 6 pages…. But my odds are pretty good considering how ridiculous the seemingly on topic responses are getting. Lol

[Dutch_12078]

Chum lee wrote:
Ever see leveling Jack's attached to the suspension? That should tell you something.

Chum lee

Leveling jacks would not stabilize the RV if they were attached to the suspension. The RV would bounce and rock the same as it does with no jacks or stabilizers.

[Chum_lee]

Ever see leveling Jack's attached to the suspension? That should tell you something.

Chum lee

[fj12ryder]

valhalla360 wrote:

red31 wrote:
I find the frame easier to access than what is behind a wheel.

But twice as high, so more likely to have the jack tip over.

My thought would be who carries a jack tall enough to reach the frame? Or the necessary cribbing to make it work? Plus you'd have to jack the frame up quite a ways to get the wheel off the ground.