I have a 39 ft trailrunner with 2 slide outs. I am seeing conflicting information. This trailer is leveled on blocks at a seasonal site where the slides stay out for 4.5 months. I have read that these slides should be supported and I am also reading not to support them as they are made to be out and be flexible to move with the trailer as it fluctuates. If supported it then maynot properly move and cause the slide to not move properly as it would then not be straight. Does anyone know which is correct?


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I too have read both sides of this. If the trailer is on solid ground (cement pad) and supported by blocks I can't see the trailer flexing due to ground movement unless the pad begins to sink into the ground. It may flex from the frame between the positions of the blocks with movement within the trailer or wind, but I can't say for sure. What I can say for sure is the Mrs. and I along with our two dogs, and two grandkids visiting every day, sleeping on the jackknife bed that it hasn't affected the performance of our slide a bit. We were camping in my daughter's driveway for 5 months while doing house searching. We just did another 3 months in her driveway recently and during all this time no effect to the slide operation. As a matter of fact, I have kept the slide extended approximately 95% of the time the 3 years we've owned it. So, I will stay with not supporting it.


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You may have noticed that Heartland doesn't suggest extra supports under the slide rooms. As far as I know, no manufacturer does. Probably the only people suggesting they're needed are the people selling them.


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I agree with no supports. My first 5th wheel a Cedar Creek, my 2012 Landmark no support. Never an issue..

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Best thing I've heard for any RV that's semi permanent is to support the RV via block/crib under the frame and get tires off the ground. If not, you'll still have movement of some sort. Supports under slides is like a tri-pod under a king pin on a 5th wheel w/ 6pt level up. Not needed.