Towing issue!

[Jcooksey]

We have a 2016 Sandpiper fifth wheel 38’, 2008 F350 diesel

Recently replaced tires and rims on truck (20” rims, little aggressive tread) and replaced tires on 5th wheel (14 ply)

Added a back sway bar for stability and still getting a sway with the trailer. We do not have air bags... wondering if anyone has suggestions on why it would be so loose? Steering is a little loose in the truck also. Do we need front stabilizers for truck? Any help is appreciated!

[007matman]

If you're steering is loose I'd check your tie rod ends. Jack up the truck by the front axle and grab the wheel at 9 and 3. Give it a good push on one side and a pull on the other. Any movement? Tie rod ends.. the inners are a little more difficult to see and you may need a second person to do this. You're looking for any movement in the tie rod end knuckle. Plenty of YouTube videos out there on how to check for this.

If you have an '08 I bet they need replacing (if it hasn't been done recently). I have an '07 and did mine last year (approx 145k on the clock at that time.

These trucks are a PITA to work on. If you're not into that, I'd take it to a shop to have it done. TRE'S are pretty easy but you could have other items that need replacing too.

[TitanMike]

Originally Posted by Jcooksey

Recently replaced tires and rims on truck (20” rims, little aggressive tread) and replaced tires on 5th wheel (14 ply)

Define "Agressive". The more "void" (space between tread elements) you have in a tire the more "squirm" a tire will have. Depending on the vehicle it can have a very noticable and undesirable effect on towing.

Also, aggressive tread styles wear far faster than standard highway type tread.

[Cowracer]

Originally Posted by Jcooksey

We have a 2016 Sandpiper fifth wheel 38’, 2008 F350 diesel

Recently replaced tires and rims on truck (20” rims, little aggressive tread) and replaced tires on 5th wheel (14 ply)

Added a back sway bar for stability and still getting a sway with the trailer. We do not have air bags... wondering if anyone has suggestions on why it would be so loose? Steering is a little loose in the truck also. Do we need front stabilizers for truck? Any help is appreciated!

Read up on "Ford Memory Steer". Seems Fords are notorious (including my Excursion) for having zero "center return" action when they get some wear in the ball joints. Bad news is, improperly installed new ball joints will also screw up steering.

What happens is: If you dial the wheel over to the left a little, and take your hands off, it stays over to the left. Like the steering is really stiff. Then you turn a little to the right and it stays to the right.

It's not really "swaying" you are feeling, but the effects of memory steer.
tim

P.s. If you steering box is 'loose' or worn, that make the effect even greater.