Tractor Trailer sway

[Luke D]

Have a 2015 Thor ACE 30.1. Just got home from a 6600 mile cross country trip. I have New Shocks, bigger sway bar, all new tires an alignment. Just curious is there are fix to the tractor Trailer suck in then push when they go buy? I thought about Summo Rubber suspension but it’s more annoying than a major issue. Any thoughts?

Thanks

Luke

[Bob Denman]

I've got SumoSprings at all four corners, and they really help a lot!

[Luke D]

Originally Posted by Bob Denman

I've got SumoSprings at all four corners, and they really help a lot!

Thanks Bob, I’ve heard nothing but good about them. Most likely my next move

Thanks be safe

[16ACE27]

Originally Posted by Luke D

Have a 2015 Thor ACE 30.1. Just got home from a 6600 mile cross country trip. I have New Shocks, bigger sway bar, all new tires an alignment. Just curious is there are fix to the tractor Trailer suck in then push when they go buy? I thought about Summo Rubber suspension but it’s more annoying than a major issue. Any thoughts?

Thanks

Luke

Have you installed a steering stabilizer?
Have you had the alignment and tire pressures checked?
Have you heard of the CHF?

[Luke D]

Originally Posted by 16ACE27

Have you installed a steering stabilizer?

Have you had the alignment and tire pressures checked?

Have you heard of the CHF?

Have new tires, front 95 PSI rears 100 Psi, have a steering stabilizer also. Front end alignment with new tires
Luke

[Jimbo56]

Originally Posted by Luke D

Have new tires, front 95 PSI rears 100 Psi, have a steering stabilizer also. Front end alignment with new tires
Luke

You say you have a bigger sway bar. Did you do front & rear? The CHF (cheap handling fix) involves changing the holes used in both front & rear OE sway bars therefore stiffening the suspension and eliminating some of the body roll.

I don’t know if your “bigger sway bars” have that adjustment.

My WB is a bit shorter than yours and probably lighter. But with the CHF, alignment, front wheel balance, and steering stabilizer I can cruise down the highway with one hand w/o side suck when passing or being passed by a semi.

[Luke D]

Originally Posted by Jimbo56

You say you have a bigger sway bar. Did you do front & rear? The CHF (cheap handling fix) involves changing the holes used in both front & rear OE sway bars therefore stiffening the suspension and eliminating some of the body roll.



I don’t know if your “bigger sway bars” have that adjustment.



My WB is a bit shorter than yours and probably lighter. But with the CHF, alignment, front wheel balance, and steering stabilizer I can cruise down the highway with one hand w/o side suck when passing or being passed by a semi.

motorhome is in my driveway. The larger sway bars where installed by a previous owner. I’ll check locations and fit. I did notice when changing oil yesterday that my front shocks look wore. Maybe part of issue.

Thanks
Luke

[Bob Denman]

Please keep in mind that you can't eliminate the sway: you can only reduce it to a manageable level.

[paulwadley]

Like Bob, I installed Sumo Springs and it did make a big difference. It makes it not so bad now. They were easy to install myself.


Paul

[Beau388]

Originally Posted by Luke D

Have new tires, front 95 PSI rears 100 Psi, have a steering stabilizer also. Front end alignment with new tires
Luke

My coach uses the 18,000 lb chassis like yours. Thor MC recommends 82 psi all around, but after weighing the coach I have settled on 75 psi in the front and 85 on the rear.

As for coach movement when passing: the bow wave from both vehicles pushes the two vehicles apart when approaching; the venturi effect sucks the two vehicles together when the vehicles are side-by-side. This causes the inexperienced driver to correct to the left as the truck's nose approaches and to steer to the right as the truck passes. The only way I have found to lessen this effect is to increase the front wheel caster.. Stiffer anti-roll bars or Sumo springs lessen the sway and make the coach feel more stable, but do not correct the basic movement.

[Mousemate]

Rear Track Bar
Took all the tail wag from passing trucks and ETC....should have done it years ago.....

[halfprice]

Originally Posted by Mousemate

Rear Track Bar

Took all the tail wag from passing trucks and ETC....should have done it years ago.....

Yep what mouse said!!

Rear track bar was the best suspension mod I did. Front sumos also helped

Most after market sway bars only have 1 hole so chf can't be done

Reduce tire pressure. You're way to high. I'm at max weight and run 80-82 on all tires

Jerry

[Luke D]

Originally Posted by Beau388

My coach uses the 18,000 lb chassis like yours. Thor MC recommends 82 psi all around, but after weighing the coach I have settled on 75 psi in the front and 85 on the rear.

As for coach movement when passing: the bow wave from both vehicles pushes the two vehicles apart when approaching; the venturi effect sucks the two vehicles together when the vehicles are side-by-side. This causes the inexperienced driver to correct to the left as the truck's nose approaches and to steer to the right as the truck passes. The only way I have found to lessen this effect is to increase the front wheel caster.. Stiffer anti-roll bars or Sumo springs lessen the sway and make the coach feel more stable, but do not correct the basic movement.

Thanks

[Luke D]

Originally Posted by halfprice

Yep what mouse said!!

Rear track bar was the best suspension mod I did. Front sumos also helped

Most after market sway bars only have 1 hole so chf can't be done

Reduce tire pressure. You're way to high. I'm at max weight and run 80-82 on all tires

Jerry

Thanks Jerry
The installer set the PSI. Probably is too high. But after 6800 miles my inner and outer threads show some wear. Not much. With the alignment done I suspected tire roll which is an under inflated trait. Had alignment re checked today spot on. Most likely shocks weak. Looking at summo front end.

[Lt Keefer]

Front sumos helped my coach's handling a bunch. So did weighing the coach and setting the tires to match the weight. I was going to do a rear track bar, but the sway is now minimal so I stopped adding mods to the chassis.