"Porpoising" - How to Tame the Rocking Camper

How fast are you driving when it gets bad?
Maybe you just need to slow down some.

What are you using to haul your camper? Some details about your truck would probably be helpful.

do you have air bags? more info about your truck certainly would help in trying to help you

Yup, without some details on your truck and its suspension it is hard to offer any educated advice.

I have my camper on dually, but even with the big capacity, I had some porpoising while having about 300 lb of waste water in my rear tanks.
Meaning COG plays big role here as well, so did you weight your truck empty and with camper to estimate COG?

First, tighten the tiedowns to correct tension. Overtightening causes extra stress on the mount locations on the Truck Camper.

Usually, porpoising is an out of balance condition. Better shocks should help. I’m assuming you have stock shocks.

But, there are things you can do before spending money. Try adjusting the Timbrens softer or slightly harder. Finally, try adjusting the tire pressure while staying high enough to support the weight you are carrying on your Tundra. The first place I’d look is probably front tire pressure since I’m assuming you are already at max pressure on the rear.

Whoa... let's consider what porpoising really is.

It is the frame of the truck flexing at or near the cab/bed location. All the weight of the camper in the bed causes to frame to flex when that weight is set into motion.

Struts are meant to dampen the movement relative to the cab. It doesn't stop the initial porpoising, it just tries to end the flexing sooner than without the struts. Previously, I had my 1181 on a 2004 F350 CC dually and my struts were effective as designed. It is too bad your camper is not meant to have struts.

Unfortunately, there is not much else you can do. For example, tightening the tie downs does not improve the frame flexing since it is the bed movement that is the problem. You will remain frustrated...

...unless you have the means to replace your truck. The Ford Aluminum Super Dutys used some of the weight savings to make the frame members fully boxed (square cross section) vs older open frame members on Fords and frames still found on most other brands (C cross section). The new frames are rated to be 24 times stiffer.

On my new 2019 F350 CC dually, I have ditched the struts and porpoising is virtually non-existent. It is a whole new driving experience for me since I don't have to watch so vigilantly for road anomalies.

Rick

Edited for spelling :(

When I first bought my Host Everest in 2012, and put it on an ‘01 F350 dually with Michelin 19.5s, I had air bags, Rancho 9000s, and upper stable loads; and it did porpoise. When I added the lower stable loads with all three wedges engaged, it became almost non-existant, just when we hid a dip in the road or big bump. Unfortunately it now rides like a tank. I had the opportunity to ride recently in a friends new RAM 3500 hauling a Host Cascade and that was like riding in a Cadillac.

I do t understand how a camper could porpoise unless the truck suspension is super overloaded, you're hauling a 10' + camper on a shortbed or you're just seeing the overhead part flex and think you're feeling it not just seeing it.

Lance 650? Doesn't take a lot of truck to haul it. What truck is it in and what is done to the rear suspension?

And feeling some weight transfer back n forth once when you hit a big dip or bump in the highway is not porpoising.