F150 porpoising under Travel Lite 625SL

la2jax wrote:
Hello,
I have just purchased a 2015 F150 (20K miles) and put on a 2017 Travel Lite 625SL (1,300 lbs).
We are getting surges frequently and every few miles there is some good bouncing. A few times we had to slow considerably to reduce excessive porpoising.
Dave

You don't mention which model F150 you have (GVWR + Max Cargo Weight). Ford data sheets (depending on the model) show a cargo capacity range from 1486# to 2558# (and everything in between). You'll either be well within the cargo capacity or close to overloaded. I'm not a weight cop but you need to find out where you're at on the charts for the full, proper fix.

That said -- is it truly "porpoising" or more of a bucking? Does the front end (rear end) rock up and down back and forth or does it feel like the bed and cab are fighting each other? One is caused by excessive frame flex while the other can be (generally) solved with shocks. Google "camper bucking porpoising" and you'll see endless discussion and possible fixes. Some acceptable - some, not so much!

Assuming you have one of the higher GVRW F150's and your camper CG is within acceptable range, I'd try a new set of Bilstein 4600's on all four corners (or Rancho 9000's). Top notch shocks are the first thing you can do to clean up a crappy ride.

I'll let others chime in here as I'm sure there will be no end to the suggestions and scolding about weight. :@

Tires and quite possibly too little tongue weight.

When I owned my half ton I installed Hellwig helper springs and c rated tires that did the trick.

What tires an shocks are you running?

I up graded to 'E' tires @ 80 psi and blistein shocks.

See my profile, I had a Travel-lite 800