Jack Location

[Jdrobone]

Howdy Folks,

Newbie here. I have worked on my own "stuff" for years now and I plan on doing my own brakes and repacking the bearings. I see a lot of warnings about where NOT to put a jack but nothing definitive on where you should place the jack. - I'm thinking a 4x4 block with a bottle jack on the frame, one forward of the 1st tandem wheel and one aft of the second tandem wheel. Does this sound right?

Jerry

[H. John Kohl]

I use one six ton bottle jack forward of first tandem. I do have to jack twice to get the wheels off the ground so I use two (three ton jack stands) one fore and one aft of the tandems. I make sure the bottle jack screw post is centered on the I beam.

Also when jacking a side I have the trailer hooked to the truck. I would not put lateral force on the front landing legs.

Welcome to the forum.

[8.1al]

John,
I'm always open to new ideas. Does placing the jack forward of the axles rather than behind work better?

Charlie

[Art-n-Marge]

Jdrobone - You have the right idea regarding the jack points per side, one in front of the tandems, the other behind the tandems. For safety sake you should consider 3 ton or higher "jack stands" versus the bottle jack. I jack up either side of the tandem starting with IN FRONT of the tandem wheels. I then use 3 ton adjustable jack stands for support on top 4x4 blocks - I don't trust hydraulic jacks for long time support since they just might creep down (you can ask how I know). Then I can keep the bottle jack available for other movements or adjustment after the rig is jacked up.

8.1al - I think it's preferable to jack up in front first so the weight of the rig stays on the wheels versus the weaker landing gear. Then jack up the rear. Using the TV is a good idea, too, unless you need the TV to make store runs.

[KTManiac]

At the Fall Rally, I watched a couple of different Dexter(axle) techs do wet bolt and brake jobs. They both required the owners to hook up the 5er to the TV, extended the landing gear to "almost" touching the ground, and used a 20 ton hydraulic bottle jack on blocks on the frame behind the rear axle. Then they placed an additional mechanical support jack under the frame for safety.

Of course, the Lippert(frame) guys might have something to say about that, but, to me, this seems to be the best way to lift the wheels off of the ground for any purpose. Personally, I think it is not a good idea to jack up the frame in front of the axles. I think that it hangs too much weight on that side of the frame behind that point. Jacking up the frame behind the axles shares more of the load between it, the pin box, and opposite side wheels, instead of hanging the weight out behind a jack in front of the axles. Draw out a quick sketch and you can visualize the difference a little better. You get a better 3 point distribution of the weight by placing the lifting jack behind the rear axle.

I have lifted one tire barely off of the ground by using a floor jack (with wood "pad") under the U-bolts of one axle. The Dexter guys would cry FOUL, but the Lippert guys probably say thats OK!

I think that is why you will never get a straight answer to the "Where should I jack up my trailer" question. They each want you to lift your unit with the "other guys" component.

If I want to lift both wheels on one side, I will do as the Dexter guys do. It seems safe and reliable to me.

[Tom S.]

I don't have the 'luxury' of being able to hook up the TV because it sticks out into the road. Instead, I securely chock the tires on the opposite side, both front and rear, plus the spreader type in between, and then put a 20 ton in front and behind the axles on the side I am raising. The jacks are adjusted to be within an inch of the frame before raising, and then raised equally - that is a few pumps on one, then a few on the other.

[H. John Kohl]

quote:Originally posted by 8.1al

John,
I'm always open to new ideas. Does placing the jack forward of the axles rather than behind work better?

Charlie

[s]For me the front of the axle is the center point of the trailer. So I feel it spreads the weight more on the frame.[/s] After further discussion on this topic it seems behind the rear spring hanger is better. Thanks - KTManiac.

[s]Either front or rear will raise the trailer and probably is not that much different.
[/s]
I like the idea of two jacks but do not carry that much weight.

Definitely use jack stands to support the trailer before you start working on it. SAFETY FIRST.

[TLightning]

I place the bottle jack in front of the forward spring hanger (that's where the manual says to put it), and raise the forward wheel, do that wheel. Then move to the rear and place the jack aft of the aft spring hanger, raise that wheel and do it. Then do it the same way on the other side.

FWIW, I never jack the trailer without it being hooked to the truck.

[KTManiac]

quote:Originally posted by H. John Kohl

...... For me the front of the axle is the center point of the trailer. So I feel it spreads the weight more on the frame......

By jacking behind the rear axle, it places the center of gravity of the trailer more to the center of the triangle of the pin, opposite tires, and the jack. This makes it an inherently more stable configuration than having the CoG closer to the one leg(jack to opposite wheels) of the triangle.



Disclaimer:
This sketch is not to scale, nor do I know where the actual CoG is. It is solely to be a visual aid to my reasoning for jacking behind the axles.

Ideally, I think the best place would be on the frame at the center of the axles, but the equalizer and leaf springs does not allow that.

That is just my take on it. Other methods will work fine. No matter how much it is discussed, if you ask 10 different people what the best way is, you will get 10 different "best way" answers on how to do it.

Take mine for instance!

[Tom S.]

Nice sketch - it gets your point across!

[H. John Kohl]

KTManiac,
Makes sense. Thanks.

[Exnavydiver]

Having done 3 wetbolt upgrades on 3 different rigs for 3 different people I found the last by far the easiest and I think the safest. We jacked behind the rear wheel with a 12 ton hydraulic. Once we got the wheels off the rig (one side at a time) we lowered the rig back to level thus removing the tilt and stress on the opposite side. We changed Dave Clark's brakes to the self adjusting units, then did the wet bolt upgrade. We used the safety stands next to the hydraulics when we lowered the rig. Once we finished the installs we just jacked the rig back up just high enough to get wheels back on. This way we minimized the time it was up and leaning to one side...Dave

[helmick]

Exnavydiver
Thats just the way Dexter did mine at the rally.

KTManiac
I like your sketch.

Ron

[jackel1959]

Any of the methods discussed here will work fine if done with the proper equipment and attention to the task at hand. For what it's worth, here is what Lippert says on the subject: Jacking the Trailer

Lots of other good/nice to know info in the "LIP Sheets" under the "Support" tab on the Lippert website: Lippert Home
Jack

[Jdrobone]

Thanks to all who posted a reply. I think I got the gist of it anyway. Good call on leaving the tow vehicle hooked up, I can see where it could "save" the landing gear
Jerry