RV moves forward when retracting leveling jacks

[cvd]

When I retract the levelers (via All Retract button), my 2025 Europa slides forward 2 - 3 inches. As the levelers start to retract, but still under load, the foot pads shutter and slide forward. Doesn't seem to matter if the ground is level or not, cement or gravel. I generally use Auto Level to put levelers down.

I've not seen this on other coaches, which had HWH hydraulic extend and spring controlled retract, no Auto Level.

1) Why does a vertical retraction cause a forward movement? 2) Seems like a lot off stress on those leveling jacks, which were designed to handle up/down pressure, not forward/backward. Anyone had problems with jack stress (bending or weld cracks)?

 

[Bob K4TAX]

First I'd say the levelers or jacks, one or more, are not perpenducular to the frame. Thus when extended will push the frame back 2" and when being retracted allow the frame to move forward 2".

Why are chocks NOT under the wheels? That is the purpose of chocks. Living dangerous my friend.

Bob

 

[png31]

When we took delivery, Demartini made a point of demonstrating this and explaining it was normal. It seems the amount of movement varies on the type of surface and how far the jacks are extended. If you watch the system operate, all four don’t operate simultaneously, but in pairs. There is enough distance between the pairs that the geometry change results in enough of an increase in distance between the jack pairs that they slide. I have not seen any problems resulting from this behavior.

 

[Judge64]

You are saying the wheels are actually moving 2 or 3 inches with the parking brake engaged or just the chassis appears to be moving forward when retracting the jacks?

 

[NXR]

Does Auto Level raise any of the fires off the ground? If it's the same LCI system used on the Georgetown it's always better to use Manual Leveling to keep from raising the coach too high off the ground.

Auto Level can only raise the coach during leveling, never lower part of the coach to get more level.

Ray

 

[cvd]

You are saying the wheels are actually moving 2 or 3 inches with the parking brake engaged or just the chassis appears to be moving forward when retracting the jacks?

As the levelers retract and the chassis is starting to lower to ride height, the leveler footpad slides forward 2 - 3 inches. There still pressure on the footpad, so the "forward slide" is a shutter.

I haven't watched the tires, but I can't imagine the rear tires turning with the brake still applied.

 

[Judge64]

As the levelers retract and the chassis is starting to lower to ride height, the leveler footpad slides forward 2 - 3 inches. There still pressure on the footpad, so the "forward slide" is a shutter.

I haven't watched the tires, but I can't imagine the rear tires turning with the brake still applied.

Gotcha.... then I would think that is normal based on what png31 said.

 

[cvd]

When we took delivery, Demartini made a point of demonstrating this and explaining it was normal. It seems the amount of movement varies on the type of surface and how far the jacks are extended. If you watch the system operate, all four don’t operate simultaneously, but in pairs. There is enough distance between the pairs that the geometry change results in enough of an increase in distance between the jack pairs that they slide. I have not seen any problems resulting from this behavior.

Yes, the Demartini rep told me the same thing; but I had the impression he dreamed up the answer when I asked the question. He wasn't bad, but he wasn't the regular customer service turnover guy (finance rep I think).

I'm not seeing responses from folks w older Dynamax's saying this is common. Makes me wonder if something is out of alignment with the lever attachment to the frame on our 2025 coaches.

 

[malmz]

2024 Europa camping on different areas and we have never had this issue. Auto level is not the best, if it is not near flat I do it manually to use ensure the wheels stay planted. I also use plastic ramps and jack pads at times and still have not moved forward at all. I would check that the jacks are perpendicular as well.

 

[Twinboat]

Look at your suspension geometry. The axle supports are hinged in the front so that as you lift the chassis it moves in an arc draging the tires foward. With little weight on them, it's not noticed.

Now when lowering the chassis, the tires and axle have to move back to the original position, but have weight on them and they can't roll.

If you can air up the suspension first, that would help, or release the parking brake while just not letting it move with gentle brake pressure.
Not sure if either is possable.

 

[bclemens]

This is normal, but with jack pads, most people don't notice it.

The fact is...even if the jacks are perfectly perpendicular to the frame....as SOON as you lift one pair, they have to move to stay perpendicular. It's just geometry. If the front goes up (as an example), the jack pad MUST move forward for the cylinder to stay perpendicular to the frame. Also, if you dump the air bags before leveling, you're automatically changing the angles, as the frame itself is not perpendicular to the ground (even when flat).

It may have more to do with the amount of pivot on the foot itself.

 

[cvd]

Sounds like it's to be expected. Thanks for the feeback.

BTW- could be the reason I'm noticing this on the new coach (and not on prior coaches), is I now have Firefly/phone based controls and can watch things more closely.

 

[M_I_A]

When I retract the levelers (via All Retract button), my 2025 Europa slides forward 2 - 3 inches. As the levelers start to retract, but still under load, the foot pads shutter and slide forward. Doesn't seem to matter if the ground is level or not, cement or gravel. I generally use Auto Level to put levelers down.

I've not seen this on other coaches, which had HWH hydraulic extend and spring controlled retract, no Auto Level.

1) Why does a vertical retraction cause a forward movement? 2) Seems like a lot off stress on those leveling jacks, which were designed to handle up/down pressure, not forward/backward. Anyone had problems with jack stress (bending or weld cracks)?

Before leveling, do you deflate the rear suspension?

 

[cvd]

Not usually. Only deflate rear bags when spot is significantly higher in back.

 

[M_I_A]

Not usually. Only deflate rear bags when spot is significantly higher in back.

Try this: With coach level, parking brake on and foot off the service brake, dump the rear air and have someone observe if the coach lurches forward. I think it will. My theory is that when you level the coach with the air bags inflated, over a couple days air will leak out and put forward "push" on the coach leaving friction of the jacks on the ground to hold the coach back. As the jacks are retracted the "push" force overcomes the jack friction and the coach rolls forward. For this reason I always dump the rear air before leveling.

 

[hitchn2go]

Try this: With coach level, parking brake on and foot off the service brake, dump the rear air and have someone observe if the coach lurches forward. I think it will. My theory is that when you level the coach with the air bags inflated, over a couple days air will leak out and put forward "push" on the coach leaving friction of the jacks on the ground to hold the coach back. As the jacks are retracted the "push" force overcomes the jack friction and the coach rolls forward. For this reason I always dump the rear air before leveling.

This is the best theory I’ve heard— and I think your fix may work.

I (like others) only dumped my air bags to assist in hitching. BUT this makes sense in that dumping airbags prior to lowering jacks puts coach in the same orientation as when getting ready to raise the jacks after sitting a while. I have just lived with the annoyance for years and just considered it as a by-product of cooling tires, etc.

Thanks for taking time to post !!

 

[KRedburn]

I have a 2018 DX3 37TS. The shudder from the jack pads is normal as the suspension takes on the vehicle load as the jacks are raised... When using auto level always check that all 6 tires are touching ground, especially the rears because that is your park brake. The fronts should never be off ground due to the chassis will be stressing your house roof seals. Even though the chassis is "rigid" doesn't mean it doesn't sage when not supported by the suspension. If auto level brings the tires off ground use the manual adjusting and a torpedo level to lower the chassis as needed to set the coach level. If you cannot acheive level the put blocks under the tires.

 

[M_I_A]

"The shudder from the jack pads is normal as the suspension takes on the vehicle load as the jacks are raised...". I want to comment that "normal" in this regard, in my opinion, should not infer OK. I am not an engineer but I think these jacks are designed for axial (vertical) loads and not transverse (horizontal) loads. A transverse load on our leveling jacks causing a shudder should not be considered normal. Dumping air before leveling is the only solution I've come up so far to prevent jack skip. Snap pads seem to make things worse because they create a lot of friction.

 

[png31]

While some here have expressed concerns about damage from “shudder”, have there been any reports of actual damage. The EQ jacks and their attachment appear stout, and I would expect are engineered to repeatedly withstand the loads encountered supporting a 15+ ton vehicle subjected wind and people moving inside.

 

[Curly50]

When I retract the levelers (via All Retract button), my 2025 Europa slides forward 2 - 3 inches. As the levelers start to retract, but still under load, the foot pads shutter and slide forward. Doesn't seem to matter if the ground is level or not, cement or gravel. I generally use Auto Level to put levelers down.

I've not seen this on other coaches, which had HWH hydraulic extend and spring controlled retract, no Auto Level.

1) Why does a vertical retraction cause a forward movement? 2) Seems like a lot off stress on those leveling jacks, which were designed to handle up/down pressure, not forward/backward. Anyone had problems with jack stress (bending or weld cracks)?

I just picked up my 2025 Europa 34SS and after the dealer setup the coach, I'm closing it up to drive home and mine lurched forward just as you stated. This issue a more common than here and there. My Tiffin Phaeton never did any lurching in the 15 years I owned it.