DT's reason for going to hydraulics over electrics ?

Diesel-Gypsy · 03-20-2007, 02:53 PM

I am trying to gather the reasons why DoubleTree opted for Hydraulic slide actuators & levelers in 2005 to present models.
The original models from 2003 & 2004 were completely electric as far as I can tell.

Looking at the specs for each model / floorplan the weights haven't changed significantly.
Why was the change made. Did everybody with the electric set-ups have warranty issues?
Were the electrics not strong enough to handle the loads?

I'm sure there are many owners here who can shed light on my search for the "real" reason.

Thanks in advance

Rick

jack_diane_freedom · 03-20-2007, 03:21 PM

And once you know these 'real reasons' what will happen? Other than you will maybe sleep better, or not.

rdunk · 03-20-2007, 03:28 PM

I don't know the "real" reason, but based upon my experiences, I was glad they made the change before I bought. Certainly hydraulics is not a new technology, but, it is often a much better way to quickly move things that are heavy, like slides, and like raising and lowering a fifthwheel.

I never had an RV with electric, but have watched other RV'ers when setting-up, and when taking-down, use the electric functions. It sure seems that things move in and out, and up and down, very slowly. With the hydraulics, those same things move very quickly.

As for the "reason", it will likely fall into either the category of product improvement/customer satisfaction, or improvement to the business model "bottom line". Whichever, IMHO, it was a change for the better, even with some of the hyd. problems some of us experienced, which were covered by factory warranty.

Diesel-Gypsy · 03-20-2007, 03:54 PM

Jack and Diane, yes I will sleep better...

I will also be in a slightly better informed position on deciding to buy a used 04 or 05 model.

A quick check of my sig.shows my present RV choice.
I am trying to settle on a used purchase decision, that's all...
I have electric slides on my Carriage, and the main slides are 13' & 14', they are slow....I guess, but no problems ..ever.

I hope whoever reads this post will understand a little better my motivation for the thread.

Thanks all,

Rick

RustyJC · 03-20-2007, 04:20 PM

We've owned 3 5th wheels, all with electromechanical (rack and pinion) slideouts and front jacks. The only problem we've ever had was a broken gear in one slideout gear reduction box of our 2004 MS RE3, and DT replaced the entire gear drive assembly including the electric motor under warranty. That's the only time our 2004 has been back to the shop since we purchased it.

Given the problems I see posted regarding the Lippert hydraulics, I'm glad that we don't have them.

JM2CW....

Rusty

rverdlm · 03-21-2007, 08:53 AM

This is our 3rd full time 5th wheel trailer. When we bought our first one I had the same concern that you seem to have. Some companies said "we will never use hydraulics because they are unreliable". Well, we bought one with hydraulics anyway because we liked the trailer and I thought the issue was a wash. It turned out to be a good trailer, but I did have one problem with the slide. We had an end seal fail on the ram. This caused some oil to leak, but the slide still worked fine. Four years later we were again in the market for a new trailer. Now the company that said never was using hydraulics and the company that made our first trailer had gone to electro-mechanical. We bought the trailer with electro-mecanical. Over the next 4 years we did have problems with this system. Bad motor and later a broken gear box. These failures put you in a bad position because the slides won't move. Both these trailers had mechanical landing gear jacks and stab jacks. While in Newfoundland the landing gear jacks seized and I had to use a bottle jack and blocks to finally get the trailer back on the truck and I was unable to unhook for several days until I was in a place where I could repair it. Dealer support and/or parts were not available in Newfoundland. Now I have full hydraulics from Lippert and I think this is the best system we've had. That does not mean it will never fail, but the effort and time required to set up this trailer is significantly improved. FWIW Teton has gone to Lippert hydraulics and they consider it to be one of their most significant improvements ever. In summary, both systems work, but neither is fool proof and IMHO should not be a deciding factor in a purchase.

Burgener_chris · 03-21-2007, 10:29 AM

The question has a simple answer, weight. These large slide outs are heavy, electric slide-out motors produce, at best, 900# of thrust. In this application the hydraulic system can produce 3000# of thrust. For many years the manufacturers compensated the lack of power by using gearboxes that were very slow. Have you ever had to look at the landing gear to see if it was actually moving when you pushed the button because it was moving so slow?

Gunship Guy · 03-21-2007, 11:15 AM

Quote:

Originally Posted by RustyJC

Given the problems I see posted regarding the Lippert hydraulics, I'm glad that we don't have them.

JM2CW....

Rusty

If you do some research on trailers using gear-driven slides versus hydraulic slides you will see the benefit of using hydraulics.

Given the problems I've seen in various forums regarding gear-driven slides I'm glad I don't have them.

No problems with the Lippert hydraulics on my trailer. Very happy with it.

RustyJC · 03-21-2007, 11:53 AM

Quote:

Originally Posted by Gunship Guy

If you do some research on trailers using gear-driven slides versus hydraulic slides you will see the benefit of using hydraulics.

Given the problems I've seen in various forums regarding gear-driven slides I'm glad I don't have them.

No problems with the Lippert hydraulics on my trailer. Very happy with it.

Actually, I'm a moderator on one of the RV forums, primarily in the TT and 5th wheel sections. As such, I have more than a passing familiarity with the technical discussions regarding 5th wheels. I stand by my statement.

Rusty

Diesel-Gypsy · 03-21-2007, 02:52 PM

I appreciate the feedback so far...
It has sparked a new question: Do both systems on the MS's have manual over-ride?

I know my Carriage 5th. wheel has easy to access manual over-rides but it will only help if the electric motor has failed, not so much if the reduction gears are done...

If there is a manual system on both types of MS systems how useful are they?
If the hydraulic system is malfunctioning due to a leak, or air, or cylinder failure, how do you ove-ride that?

Rick

RustyJC · 03-21-2007, 03:13 PM

The MS electromechanical system is similar to your Carriage. The manual crank only works if the gearing is intact. After our gear failure, I picked up a couple of "come-alongs" to winch the slideout in if we had another failure. As is usually the case, if one has the tools, he never needs them - we haven't had any problems since that single gear failed.

Rusty

Hobo · 03-21-2007, 08:05 PM

With the hydraulic system you need a drill motor to drive the pump as a manual over ride. As with the gear box system this also has it faults. If it is a valve failed or the hydraulic pump motor is locked up your up the creek.

My last trailer with hydraulics had a handy hand pump like a hydraulic jack that could bring the slides in with no power and little 3elbow grease.

Rick

bstark · 03-22-2007, 12:21 AM

Although the "manual over-ride" of this system is only good if the system integrity other than the pump motor is still intact, I don't believe we are "up the creek" necessarily. I would depend on a couple of things like the ratchet strap type of load binders to pull in my slideouts. You could attach a strap at one end of the slideout and if the alignment rack is still intact, the slideout should come in parallel. The bedroom slideout could be brought in the same way by attaching a ratchet strap to framing under the bed once the mattress is lifted and cover boards removed.

I haven't looked closely but perhaps there is an access method to get to the ends of the alignment shaft (the shaft with the gears on it that mesh with the tracks under the slideout supports) and if so perhaps even a rachet handle could be used to turn that shaft and bring slides in or out??

As mentioned by previous poster; this is our second trailer with hydraulic system and have had no problems with either unit.

**wingnut60** · 03-22-2007, 11:07 PM

Since this is about hydraulic slide systems, thought I'd ask about a problem I am having. Just bought a used '05 36TK3 and everything has worked fine for the little amount of time I have had it. However, when trying to raise the bed, it doesn't work, and it appears the bed slide is trying to move--just a slight movement in/out depending on which way the button is pushed on the bed lift.
All the slides work fine, and the problem exists whether the bed is in or out.
It did work fine the first 2-3 times I used it just to see how it works.
From reading earlier posts, I have determined that the valves are all open fully to the stops, and there is plenty of fluid in the resevoir when all slides are in.

Any suggestions?

rverdlm · 03-23-2007, 08:49 AM

Get under your bed and see if everything is still OK. The arms that lift the bed will sometimes bend. Also the hydraulic ram screws will pull out of the floor. I posted on on Yahoo groups how I fixed mine and it's been great since. Here is that post;

We've had problems with our power lift king bed. I have not seen it
discussed so I don't think it's a big issue. However this is what
happened. The hydraulic cylinder pushed and after a few lifts the arms
that lift the bed turned into pretzels. Walnut Ridge said they'd seen
this before and the fix was to strengthen these arms, which they did.
Well that lasted about 2 lifts and the "U" channel that holds the ram
(it's held to the floor with 6 screws) ripped out of the floor. Now
for the good part! Yesterday I took everything apart and drilled more
holes into the "U" channel. It's now held to the floor with 16 bigger
and better screws. It seems to work very well. Only time will tell for
sure. While I had everything apart I removed all the springs and the
fabric that they held. BTW the fabric was tearing the bottom of our
Select Comfort mattress. I replaced the fabric with 2 pieces of luan.
Now the bed covers don't catch on those d__m springs. So far so good.
It seem like a big and easy improvement.

Hope this helps.

**wingnut60** · 03-23-2007, 04:59 PM

rverdlm--thank you for the response, I will inspect the arms as soon as I get back home.

Joe

Jimfla · 03-23-2007, 06:56 PM

I work on hyd. for a living I woulden't buy a trailer with hyd. slides wait til a hose brakes under bed or in unde belly , the reason they went to hyd is $ hyd. is less than half of th cost of elect. 8 electric motors instead of 1 just my opinion

PS. this came from an engineer at DT who is no longer there JIM

Diesel-Gypsy · 03-24-2007, 06:04 PM

Et....VOILA...the real reason.....!
I guess.

Rick

dave007 · 03-26-2007, 08:59 AM

I have had lots of work experience with hydraulics. The thing that first impressed me about the DT was the hydraulic slides. I think having 6 or 8 electric motors to go bad is more risky than one hydraulic. Just keep the oil level full and the fittings tight and you shouldn't have much trouble. I'm much more comfortable dealing with a little hydraulic fluid than tracking down electrical problems. Just my opinion....Dave

WildJohn · 03-29-2007, 10:01 AM

I also worked with hydraulics for a long time.. but on my own... and I had to pay the bills... just the hydraulic hose is enough to make multiple motors look pretty attractive... when you think of two hoses for each cylinder and the distance they are away from the pump... quite a bit of money. I doubt if the difference in price is the real reason myself...I personally like the hydraulics. If I were to change, it would to put the BigFoot leveling system on..