Tundra/Tab 400 bouncing while towing

Tundra57

I have a Toyota Tundra TV. 2010. Also a Tab 400 2019.

Since i had the truck, it has a common issue where on roads that have rapid horizontal undulations, the truck magnifies them to where it is annoying. Some mods were made to the model to reduce this. Keeping the tires rotated and balanced well helps greatly.

On my long trips down South, there are stretches of I81 where the roads gave these lateral cracks close together. When towing this sets up a resonance and my Tundra/Tab have this vertical see- sawing. It is worse above 60mph even at 40mph its annoying. Some air in my airbags helps, but too much makes it worse. (I usually run 20psi, but 15 seems optimum when bouncing). I just changed the Bilstein rear shocks, which were not bad, just in case, but no difference. Also tried the rubber mounted tow hitch ball, which i think makes it worse.

Anyone know of anything which fits between the TV and Tab to damp this?

In England I had a damper which was a wide spring bar with a friction joint which was bolted to the TV and the bar rested on a u channel on the Trailer. The friction joint (horizontal) damped sideways swerving and the spring bar resisted the vertical flexing motion.

I just would like the vertical damping.

Haven't seen anything. An equalising hitch would be overkill i think.

ChrisFix

@Tundra57
A WDH might actually be the exact thing you need for this. While it may seem on paper like overkill for your rig, many people report a smoother more well mannered tow after adding one to their rigs.
The Fastway E2 seems like the one that best fits our T@Bs:
https://tab-rv.vanillacommunity.com/discussion/8518/fastway-e2-wdh-installation

Another item you might want to look at are the Gen-Y Torsion hitches. I'm using this one:
https://genyhitch.com/product/the-glyder-torsion-flex-hitch/
It's a properly designed (and built) version of the rubber mounted hitch ball you may have already tried. A bit spendy, but truly built to tank-like standards. But for what you're describing, my bet is a WDH would help you out more than the torsion hitch, although the torsion hitch is specifically damping/isolating just the vertical motion you mention.

Denny16

If the Tundra has light duty springs, this will make the vertical sea sawing worse.
I had a similar issue going over rough roads, lots of them where I live, and with 400+ lols balanced on the rear of the tuck, it would bounce up and down some.  I changed out my rear springs and shocks for the Jeep MaxTow progressive springs, that have more resistance when compressed, and will better control a up and down bouncing motion when loaded down.  

Also try just throwing some weight in the back of the truck  bed, I had to do this with my Dakota truck, which was bouncy when empty.  I also swapped out the Dakota stock shocks for Monroe Load Lever shocks, and this helped also.
cheers

Bayliss

@Tundra57, have you considered trying a hitch tightener?  They are inexpensive, so it might be worth a try.  I am not exactly clear on the vertical movement you are describing (sounds like the bounce you would get with really bad shocks, but you have changed those.)  Maybe the coupler has enough play around the hitch ball, which is causing the up-and-down movement?  I have a 2007 Tundra and there is a little bit of play in that connection (although I only notice it when stopping or pulling away from a stop, and it is slight), so I am planning on giving a hitch tightener a try.

Deb55

We use a weight distribution hitch and sway bars when towing the 400 with our F150. We bought them when we were towing with a Highlander and just continued to use them. Even so, on some roads, it does get annoyingly "washboardy."

AirBoss

@Tundra57
Like @Denny16, I swapped out all four shocks for Bilstein shocks designed for heavy-duty SUV's and replaced rear coils with Moogs.  Made a world of difference, but then they were due to be replaced anyway.

I have to say a WDH and/or Torsion hitch are far less expensive and likely will go a long way to solve your issue. May go the Torsion hitch route myself. No much in the way of porposing anymore but it's noticeable from time to time. 

Good luck...keep us posted on your choice. 

Tundra57

My truck has rear leaf springs, i wouldn't say they are light duty tho. I have not tried the add a leaf just to see if it helps. Im inclined to try an equalising hitch or maybe the tosion hitch. @ChrisFix, what makes you think the WDH would be better than the torsion hitch?

Tundra57

Anyone tried an air shocker hitch?

ChrisFix

Tundra57 said:

My truck has rear leaf springs, i wouldn't say they are light duty tho. I have not tried the add a leaf just to see if it helps. Im inclined to try an equalising hitch or maybe the tosion hitch. @ChrisFix, what makes you think the WDH would be better than the torsion hitch?

@Tundra57
Because it creates more of a unified motion between TV and Trailer...possibly damping the porpoising...whereas the Gen-Y Glyder I *think* helps more with smoothing out the abrupt bouncing like a pothole or action that affects each axle separately.  

Tundra57

@ChrisFix. I see. Since the hitch is a ball and socket, damping the ball wont stop the trailer movement much. So i'll try the equalising hitch with damper just for its damping characteristics. Dont need its levelling ability.

ChrisFix

Tundra57 said:

@ChrisFix. I see. Since the hitch is a ball and socket, damping the ball wont stop the trailer movement much. So i'll try the equalising hitch with damper just for its damping characteristics. Dont need its levelling ability.

That's what I'm thinking as well. While you don't need the leveling ability that is the usual driver for using a WDH, it has the benefit of a more controlled ride, in addition to its anti-sway control.
I hope you find a solution that works great for you.
I've been so happy with my set up in regards to it's towing comfort. I have to believe with your truck's capability there is a setup that makes the T@B virtually disappear regarding towing it. 

Tundra57

@ChrisFix thanks. Im going to give it a shot lol. As long as the road is reasonably smooth, it tows great. :-).

Tundra57

Anyone tried the Anderson 3347 hitch? Its supposed to damp the vertical pitching motion.

Denny16

 Looks interesting, better than the rigid arm load lever hitches.
cheers

AirBoss

Does look interesting. At $600, it had better eliminate sway, eliminate porposing, and make me coffee in the AM! 

Tundra57

You would be surprised how expensive some of them are.

I am ordering one today, but like a lot of RV items, they are on backorder 3-4 weeks.

Its these newcomers fault lol.

AirBoss

No kidding!  Seems everything I want to order lately (Maxxair Deluxe now on back order) is flying off the shelf. 

Is it too late for me to open an RV sales and service center? Its like printing money right now. 

DenisP

@Denny16 @qhumberd I have not experienced any issues with porpoising while towing. It may be how my truck and 400 are loaded but not a problem I remember nor my DW remembers. I have a 2013 TRD 5.7l with Michelin Defender LTX tires and an ARE truck cap. I usually travel with near empty tanks and carry 2 six gal water tanks in the truck bed. Maybe it makes a difference? I have checked my tongue weight a few times with scale and fully loaded in the 450# range. 

I had a Reese round bar WDH when I first got my 400 but abandoned it after reading posts about possibly overloading the Tab’s 3500# axle when sharing the Tundra’s 6000+ weight. The WDH had a long receiver which allowed for an unobstructed access to the tailgate which I appreciated. I replaced the WDH receiver with : CURT 45260 Class 3 Trailer Hitch Ball Mount, Fits 2-Inch Receiver, 7,500 lbs, 1-Inch Hole, 2-In Drop, 3/4-Inch Rise https://www.amazon.com/dp/B0007M308U/ref=cm_sw_r_cp_tai_HQtkFb9HMC7RC. The extended 12.5” receiver maybe contributing to the lack of porpoising. 

Added: I also use a simple friction anti-sway bar. 

Tundra57

@DenisP do you have the double cab version? This is most susceptible. I did not try adding the extra bed weight tho, It could help. That will be on my list. Its only a particular type of road problem. Bumps and rough road are not a problem. Good advice on the reese overloading. Ill make sure not to try and share too kuch weight with the tab. Just want to see if the chain and rubber shockers will damp the movement as i travel this road regularly.

Lloyd

Tundra57, have you considered the ball height on your TV as a possible source of your bouncing? It would seem plausible that if your TV ball height was not matched to your T@B 400, a vertical oscillation could be introduced when towing over undulations. I don't know if there are any data or specs on tongue height for the T@B 400 and I don't recall ever seeing any. Anyway, just a thought.

DenisP

@Tundra57 I have a 2013 TRD Double cab 4x4 5.7l and ARE Z series Truck cap.  I also changed the Tab’s tires to Goodyear endurance tires and maintain 62 psi. I usual travel at 60 mph. I hope this info helps. 

Tundra57

@DenisP . That explains a lot. Toyota made some frame and bed connection changes aroubd 2012. I have cooper off road tires. They are only at 35psi.

I also had hankook tires, much less agressive they ran 55psi but the same problem.

So im not sure tires or pressures help. @Lloyd, I do run the tab and Tundra level.

Maybe i could try a non agressive road tire.

Ill see what the chain equaliser hitch does for me.

grsiepka

I've got a 2018 tundra platinum(crewmax with short 5.5ft bed) and Tab400. Truck is stock other than tires replaced with Nitto Ridge Grapplers on the 20" platinum wheels.

When I switched from the 4runner I kept my Fastway e2 WDH and adjusted it to fit the Tundra. I also use hitch tightener ubolt thing to prevent the hitch from wobbling around in the receiver.  To be honest I've only done a couple hundred miles so far with the Tundra but don't think I've experienced what you're describing. Maybe the WDH is preventing that?