Passenger slide extended 6-8" while driving

[DVerstra]

While driving through a hilly area with a lot of curves in the road, our passenger side front slide worked its way out. I looked in my mirror and it was out about 8". I found a pullout and placed the transmission in Park. Then I brought the slideout in. The entire slide was out not just one corner. It is a hydraulic slide. The valves and reservoir tank are under the front stairway with access through the step. I checked the reservoir and the fluid is correct on the short dipstick. What are the possible causes? I'm thinking of either a valve that is allowing the fluid to bypass or a cylinder issue.

[Frank McElroy]

Yes, you have a leaking valve.  Likely a small amount of debris is keeping it from fully seating.  When bringing in the slide hold the slide in button for a few seconds until you hear a pitch tone change from the pump.  This might clear the debris from the valve seat.  This file might help you if don't already have it.  (If you click on the title "HWH Hydraulic Flow Diagrams" you will get an option to download 9 individual files.  The last one is a diagram of the valve locations for the slides.)

 

[Jdw12345]

It is also possible that you have a small hydraulic leak in that slide system, I found I had a leak at the pump last summer and I had a hydraulic pressure regulator for my rear slide on the passenger side go bad, As stated above by Frank, it could be a bit of debris in the system check valve or it could be a bad check valve too.

 Here’s a picture of what failed on mine.

 

 

Edited February 9, 2023 by Jdw12345

[Ivylog]

Because there’s a synchronizing cylinder in the system it’s actually a good idea to not immediately let up on the switch when the slide stops moving… not going to hurt anything and it may move the debris from the valve.

[Tom Cherry]

DITTO on all the comments.  I knew the "TIP" to always hold the slide button in for a second or so.  As a matter of protocol and habit, when I retract the slides, I quickly hit all the buttons one more time.  YES, the rear electrics are not an issue  BUT, the front ones (Lippert Hydraulic) have the balance cylinder or the sync valve. 

We use our MH more than most.....we have spent over almost 1.75 years out (nights) and we average about 2.5 nights per stay plus we have been on 62 separate trips and each trip we packed at home and extended/retracted the slides....as well as coming home. 

So....on trips, our slides have been out and in some 248 times....then add in 124 in and out when packing.....almost 400 cycles.  We have had ONE instance where a slide drifted.  It was in storage about 5 years ago and it drifted out maybe 4 - 6 inches.  I did the on and off and purge trick....whatever was in there.....went away....as we used it for three very long trips since then.

My logic would be to do as Frank says. Exercise the slides and make sure you hold the button in and hear the pitch change....not for 5 seconds....but OK....IT IS OK type of count....  Then keep doing that....Mine never, ever drifted while driving...

Good Luck. 

[DVerstra]

Thanks for the help on this. I don't see any leaks. I'll try the "purge" idea and see if the problem goes away on the next drive.

[Mike H]

Last June right after we returned from Death Valley the synchronizing cylinder for the driver side slide blew a seal.  I wasn't paying attention while trying to retract it and the slide tried to come in crooked and ended up getting bound up part way in.  couldn't extend it back out or move it at all.  It sat in our driveway and took almost 2 months before I finally got help to get it straight and back in.  Lazydays pulled all 3 of the hyd cyl's out so I could get them rebuilt and reinstalled.  Because nothing was labeled on the pump wiring or solenoids, that slowed the trouble shooting process.  I ended up making a chart identifying what each solenoid was for and stapled it to the bottom of the step access cover.  Next step I plan on labeling all of the wiring.  You'll notice that when the slides are extending the cylinders are retracting.  I just thank GOD this didn't happen while we were camping out in Death Valley !  BTW, it cost $110/cyl to have them rebuilt but the Lazydays bill was just under the 5 figure mark!  Fortunately they didn't have to remove the slide but did have to repair the damage to it.

Edited February 10, 2023 by Mike H

[dennis.mcdonaugh]

Your coach should have come with two slide locks to keep that from happening if the hydraulics fail.

Ours came in crooked a couple years ago and I ended up replacing all the hoses and having the synchronizing cylinder and front and rear rams rebuilt.  I also relocated the sync cylinder to a more accessible location in the basement overhead.  Luckily, the slide didn't get stuck, it just jammed up the inside facia trim around the slide box. While I was reading all the literature about replacing the hoses and rams, I found a short blurb that said you shouldn't reverse the direction of travel without fully extending or retracting the slide.  I never knew that.

Edited February 11, 2023 by dennis.mcdonaugh

[Mike H]

3 hours ago, dennis.mcdonaugh said:

Your coach should have come with two slide locks to keep that from happening if the hydraulics fail.

Ours came in crooked a couple years ago and I ended up replacing all the hoses and having the synchronizing cylinder and front and rear rams rebuilt.  I also relocated the sync cylinder to a more accessible location in the basement overhead.  Luckily, the slide didn't get stuck, it just jammed up the inside facia trim around the slide box. While I was reading all the literature about replacing the hoses and rams, I found a short blurb that said you shouldn't reverse the direction of travel without fully extending or retracting the slide.  I never knew that.

I've heard that as well but don't really understand why and I know I have been guilty of that in the past.  After we got it all repaired and took a Fall trip up north I noticed Hyd fluid on our driveway when we got back home and had to have all of the passenger side slide cylinders rebuilt.  Luckily nothing was damaged that time other than my wallet again.

[DVerstra]

10 hours ago, dennis.mcdonaugh said:

Your coach should have come with two slide locks to keep that from happening if the hydraulics fail.

Coach did not come with slide locks that I know of other than the Driver side front slide has a lock mechanism. I don't see a way to insert a slidelock on the passenger side. The passenger side slide is within an inch of the ceiling when closed and has an accordian style cover on the side.

[DVerstra]

Quote from Frank McElroy

"Yes, you have a leaking valve.  Likely a small amount of debris is keeping it from fully seating.  When bringing in the slide hold the slide in button for a few seconds until you hear a pitch tone change from the pump.  This might clear the debris from the valve seat. "

I used this method when closing the slides. Woohoo! It appears to have worked. No problem with slide extending during trip North from Florida.

Thanks Frank and others for this TIP