Please help me understand the Rear Sway Bar argument

I second this. I live in Castle Rock. Home to the I25 bed bounce. I saw no difference in bounce after install.

 

You can see the bed bounce in the side mirrors. The bed is flexing up and down at the back of the cab.

All the mentioned suspension changes will help with it, but none of them cause the frame to stop bending so much at that point. I love my tundra, but yes it is a horrible design flaw. Mitigating the effects are a great start!

Forgot to say too, yes other trucks have this problem, not all. Watch a 2004 superduty on the highway and a 2019 superduty on the highway, the 04 frame flexes all over the place, the new ones are much more rigid

 

The rear sway bar can be had for less than $200 and installs in the amount of time it takes to drink a beer. Buy it, install it, run it. If you don’t like it, you can sell it in a day for barely less than you paid for it. Problem Solved

 

I bought a 2014 Limited double cab in May of ‘19 and after driving it for a few months decided that I wanted to improve the ride quality. Like you and many others on here, I too have experienced body roll as well as bed bounce and have been looking at options to improve this. Here are things I have done and some thoughts to go with them:


TRD Rear Sway Bar – of everything I have done this is by far the most noticeable improvement. To be clear, it will absolutely improve how your truck corners by reducing body roll but it may worsen bed bounce slightly. To quantify it, I would guess 80-90% improvement in body roll and maybe a 5% worsening in bed bounce – I have no actual data for this, it is just how it feels for me. For ~$250 this is the best bang for your buck option and well worth the small sacrifice in bed bounce (if any).

Coachbuilder +1 shackles w/ poly. bush. – I did this before the rear sway bar and found it to be a minimal upgrade to both body roll and bed bounce. It might just be a placebo effect but it seemed like it help a little (10%?). For ~$300 it might be worth the effort…

18” wheel – I went from the stock 20” Michelin’s to a set of 18” TRD takeoffs I found on Craigslist. My tire choice was the Nokian Rotiiva AT Plus LT275/65-R18. Maybe another slight improvement, say ~10%. Just enough to think you’re doing something right but not quiet sure if you’re being honest. If anything, I think a P rated tire would help the most. Not worth thinking about till your current tires are worn out.

Bilstein 6112/5100 – Did the rears first and felt an improvement after a few days as it seems they needed a break in period. Better than the wheels and shackles, maybe a 15% improvement, but still not significant like the RSB.. I’m not happy with the 6112’s BUT I haven’t given them a fair shot yet. To be honest, they’ve only been on there 2 days so they still might need time to break in. That said, my first thought is that they are much stiffer than the common black shocks that come on many stock Tundras. And if you're curious, the front coilovers are set to the lowest setting (.75” lift I believe) and I just got an alignment after I did the install.. Like I said, it needs time, but I am a little worried that this may have been the wrong move. So far, definitely not worth the money..


That was a lot longer than I thought it was going to be but there seems to be a lot of misleading information out there – or biased opinions anyway. Hopefully that is honest/objective and will help you make a decision.

 

Unfortunately your not going to get a consistent answer. One mans rough ride is another mans smooth ride. I have done nothing to my Tundra. Stock 4600 bilstiens no sway bar and I think the truck rides great. It doesn't jump around over rough road surfaces seems to stay planted like it should. I don't even think there is that much body roll in corners. I am not sure how fast some folks think you should take a corner in a truck but at the speeds I go the tundra does as good as any other stock truck I owned.

 

I’m in the same boat where I don’t want to lift my truck but would like to help the bed bounce. There are a lot of threads on this and I have concluded that the Coachbuilder +1 shackles with poly bushings seem to help the most. Since I don’t want the lift, I ordered just the bushings. Still waiting on them to ship. I can let you know the difference once I install them. I also have front and rear TRD sway bars. I did notice it’s stiffer when driving over gutters and other typical large street bumps as the daily driver. But not enough to dislike the ride. I prefer to have them to have a flatter ride on corners.

 

I have don't have bed bounce even running BFGs at 50 psi. I have followed F150s with bed bouncing like crazy. Fact is a bed designed to haul a load is going to bounce when not loaded. Load the bed or buy a Caddy if you don't like bed bounce.

 

OP, perhaps someone near you owns a Tundra that is set up a bit different than yours? Maybe there's someone near you that would take you on a ride or let you drive their truck for a short time? After six years, the stock shocks are probably at the end of life as mentioned by others. They don't last forever and cannot be rebuilt.

 

Was the 200lbs your experience or are you guessing. I added 400-500lbs of cultured stone boxes for my fireplace and it made no difference to the bounce on I-25 here in Denver.

 

It’s a pick-up truck , not a Porsche, I say just slow down . But to each his own

 

Both. I had 200ish lbs of sand tubes between the tailgate and cargo divider behind the rear wheel.

I live in a place that doesn't use segmented roads though, so what we do have is minimal. I recall living in the Midwest the highways were much worse.

 

Lots of good info regarding Rear Sway Bar.
marking it for a potential future mod.

 

after reading some of the front/rear sway bar threads, something doesn't make sense to me.

the real TRD models (not the added TRD package) come with rear sway bar from the factory and the SR5 or limited don't come with rear sway bar.

I was expecting the opposite since TRD trucks are supposedly doing more "off-roading" and no need for rear sway bar... and regular (non TRD) trucks are expected to do less off-road (more city & towing) and better to have rear sway bar ...

Maybe @Rex Kramer knows what's going on?

 

Toyota Racing Development

I have always considered racing to include sharp handling & cornering at speed, and anti-roll bars (sway-bars) are required if you want sharp handling & cornering at speed. Pavement is where most 'racing' occurs, and I prefer to keep my vehicles on the road - off roading is a foreign concept to me. Marketing & packaging are concepts I am familiar with... Toyota often sends mixed messages with their marketing & packaging, perhaps to expand their reach into the market.

 

Good info @Rex Kramer

Forgot the R in TRD is for Racing ...

I thought TRD package meant off-road package since my car has a big TRD OFF ROAD sticker on the side.

So I have a off-road Racing package. In my case, since I don't have a real TRD truck, the off-road package removed my rear sway bar. lol
I guess it kind of makes sense.

I'll keep that in mind next time I go to the grocery store. maybe I can find a little gravel road somewhere in the neighborhood.

 

The contrary I believe. Most Tundras don't come with a rear sway bar only a front. I added the rear to mine, and changed the front to the stiffer one. I like the feel of the stiffer suspension, and minimal role in curves. I don't go rock crawling, I do go off the road in loose sand and dirt, not mud bogs.

 

i added both front and rear red trd sway bars and my trd pro went from boat to planted....but doing so made it more bouncy/jittery on some roads...then i added rear shackles and BAM!!!! best ride going. its like combining a mustang and a cadillac into one ride... just like magic. TOYOTA TUMUSTCAD TRD PRO
here is my video...

 

Poly bushing from CoachBuilder actually eliminated / reduced the bed bounce for me without shackles.

 

So you press out the bushing on the spring end and replace it with a solid poly piece, no pressing back in? I'm looking for anyway to reduce the bounce that was introduced by adding the rear sway bar, beyond adding weight to the bed.

 

Exactly - new poly bushings slide right in. The factory bushing can be a b!tch to get out though... lots of threads on this topic.

 

No pressing back in. Each poly bushing is two halves and sleeve.

 

Good thread here:
https://www.tundras.com/threads/installed-coachbuilder-shackles.66757/

 

Thanks, not worried about that so much. I'll get a press and I have a sawzall if it comes to that. I just didn't want to to deal with pressing back in, but don't have to!

 

Your tunny is fairly new so pressing out the OEM bushing shouldn't be a total beyatch.

 

You got a newer truck so shouldn’t be too difficult with the right tools. Mine came out fairly easy with a ball joint press in one piece. After that it’s easy as pie.

 

A little old post, but I think you are refering to the TRD Sport package that actually comes with Rear Sway Bar, 20" rims, and On road tuned suspension.

 

The rear sway bar argument is simple.
Just like a front sway bar, it reduces body roll and improves handling in non-straight line driving.
A sway bar is intended to equalize weight distribution across both sides of the truck. This helps stabilize the chassis in turns and reduces weight loading on the outside tires (and improves contact patch of inside tires) in a turn.
There are 2 scenarios in straight line driving that have different outcomes depending on sway bars.
Scenario 1: Truck traveling in straight line hits speed bump, both L & R side are loading equal, axle travels up and there is no impact to ride quality from sway bar. struts + springs absorb all energy.
Outcome is the same as no sway bar.
Scenario 2: Truck traveling in straight line hits pot hole on R side, axle is loaded unevenly, R side travels upward, sway bar transfers upward motion to L side and creates L to also lift-up slightly.
This action with a sway bar is loading and unloading each side until a balance is reached and the shocks mitigate the motion. This outcome is different between sway bars and no sway bars and can be interpreted as jarring or bed-bounce. Others have mentioned bed-bounce being different and it is, but not everyone is familiar with the dynamics of how leaf spring suspensions function. Being in automotive, everyone "feels" and 'interprets" things differently. Hence why quantifying things is important, and numerical data is king.

 

maybe there are different models or package options. mine says TRD 4x4 OFF ROAD on it and came with 18" rim and no rear sway bar. I am sure it has a front sway bar but if I understand it correctly the real TRD models have a thicker front sway bar and also come with rear sway bar. Mine has an optional TRD off-road package but is not a full TRD model.

 

When you say "full TRD model" are you referring to a Sport or a Pro? 90% sure the only trim that has the rear sway bar as standard feature is the TRD Sport. Because the Pro is advertised as the most off road capable trim it doesn't come with a rear sway bar.

 

didn't know there are 2 TRD models. Based on what you are saying it sounds like TRD PRO doesn't have the rear sway bar but TRD sports does.

my truck is not a TRD PRO and I'm sure is not TRD Sport either because it didn't come with the rear sway bar.
it has the optional TRD off-road package because I have seen trucks that say TRD PRO on them and not many of them ... Mine just says TRD 4x4 OFF ROAD.
Maybe I should buy some tape and stamp "PRO" on it. J/K