The wife and I just bought a used 2008 travel trailer. The seller told us to use the slide supports that he bought for the slideouts. I thought I read somewhere not to use them. We are fairly new to all this so your advice would be appreciated.
I wouldn’t use them unless your specific trailer manufacturer’s manual says to. Most slide-outs are designed to support themselves when fully extended, and aftermarket supports can actually cause damage if the trailer settles or shifts while the support remains in place. Level and stabilize the trailer itself, then extend the slides according to the manufacturer’s instructions.