Rear suspension product advice for towing

[MtBiker19]

Folks- I've towed my Airstream a few times this summer and would like to focus my efforts on upgrading the rear suspension.
The combination tows perfectly fine on the ball with a Shocker hitch. Its a 22ft trailer, Im guesssing around 4000lbs total (still need to find a CAT Scale) with a 400lb tongue weight (verfied with a B&W digital tongue scale). Its in the 10% range and I am still managing cargo and water payloads front to rear with the trailer. I still have some homework to truely nail down what my weights are so that I can get things balanced and within spec.
Every once in a while, I can get a little wiggle from the rear end. Its tough to tell if its wind related or simply a strange undulation in the road surface. That being said- when its time for new tires I plan on switching out the stock 20in Dunlop Grandtrek PT22 to Michelin Defender LTX M/S2 (which I assume would have a slighly stiffer sidewall). Not really sure that I want to jump to the E-Load Michelin Defender LTX Platinum.
Additionally- I would like to upgrade the rear suspension when I do my next service. This truck is my daily driver and I use it a lot for work travel in stop-and-go DC traffic. We very rarely take the truck off road or go exploring fire roads- as we always bring our pups and I dont need motion sick doggos. The truck has been on the beach in North Carolina, but when its being used as a truck- thats towing the Airstream. ...and Im not looking to add any addtional lift height.

I've narrowed it down to three options.
* Timbren Suspension Enhancement System - Rear Kit - TORSEQ3
or
*Dobinsons 0-2″ Lift Rear Coil Spring - C59-883V
*OME Coil Springs – Heavy Rear - OME3339

Thanks as always for the input.

 

[MSINAL]

You might be surprised how well rear airbags help with towing and heavy cargo loads. Our 2dr wrangler is ultra stable towing after i installed airbags. When not towing i deflate them to the minimum. Airbags are the best option for quick adjustments for levelling.
Additionally, offroad you can increase the height at rear axle if you high center.

 

[Bad1975]

I'd put coil spring lift/towing bags in first before swapping out to new springs. Is your trailer single or dual axle, single axle is harder to limit sway. Next step would be a weight distribution hitch setup for me.

 

[MtBiker19]

You might be surprised how well rear airbags help with towing and heavy cargo loads. Our 2dr wrangler is ultra stable towing after i installed airbags. When not towing i deflate them to the minimum. Airbags are the best option for quick adjustments for levelling.
Additionally, offroad you can increase the height at rear axle if you high center.

I've thought about air bags, but may have to give that a second look. What kit did you go with?

 

[MSINAL]

Folks- I've towed my Airstream a few times this summer and would like to focus my efforts on upgrading the rear suspension.
The combination tows perfectly fine on the ball with a Shocker hitch. Its a 22ft trailer, Im guesssing around 4000lbs total (still need to find a CAT Scale) with a 400lb tongue weight (verfied with a B&W digital tongue scale). Its in the 10% range and I am still managing cargo and water payloads front to rear with the trailer. I still have some homework to truely nail down what my weights are so that I can get things balanced and within spec.
Every once in a while, I can get a little wiggle from the rear end. Its tough to tell if its wind related or simply a strange undulation in the road surface. That being said- when its time for new tires I plan on switching out the stock 20in Dunlop Grandtrek PT22 to Michelin Defender LTX M/S2 (which I assume would have a slighly stiffer sidewall). Not really sure that I want to jump to the E-Load Michelin Defender LTX Platinum.
Additionally- I would like to upgrade the rear suspension when I do my next service. This truck is my daily driver and I use it a lot for work travel in stop-and-go DC traffic. We very rarely take the truck off road or go exploring fire roads- as we always bring our pups and I dont need motion sick doggos. The truck has been on the beach in North Carolina, but when its being used as a truck- thats towing the Airstream. ...and Im not looking to add any addtional lift height.

I've narrowed it down to three options.
* Timbren Suspension Enhancement System - Rear Kit - TORSEQ3
or
*Dobinsons 0-2″ Lift Rear Coil Spring - C59-883V
*OME Coil Springs – Heavy Rear - OME3339

Thanks as always for the input.

Do you increase LC tire pressures when towing? This helps as well. I run 33psi unloaded, and 39 towing. Im only towing half your weight however.

 

[MtBiker19]

I'd put coil spring lift/towing bags in first before swapping out to new springs. Is your trailer single or dual axle, single axle is harder to limit sway. Next step would be a weight distribution hitch setup for me.

The trailer is a single axle- and yes I do understand those are a little more lively than a dual axle. I've been really reluctant to go down the WDH path, becuse of additional equipment/steps and factoring backing up and really tight turning radius that I currently have. The trailer weighs less than the 5000lbs that Toyota calls out in the manual for requiring a WDH- and for sway- the manual says anything above 2500lbs should have sway control. I currently have a Curt True Course Trailer Sway Control, which essentially can hit the brakes faster than I can pinch the brake controller. And I've been on the fence regarding mechanical sway solutions including WDH. The truck sits near level with the trailer attached, and with a fairly low tongue weight, a majority of WDH's are overkill with their weight displacement ratings on the bars.
Basically- I currently have a serious case of paralysis through analysis.

 

[MSINAL]

I've thought about air bags, but may have to give that a second look. What kit did you go with?

Check out this thread. I dont have bags on LC yet, but will install soon.

Air Lift 1000 for the LC

Anyone running these or another alternative? Their site doesn't show a LC but they have them for the Taco and 4runner. This kit was common on FJs. https://www.airliftcompany.com/vehicles/toyota/4runner/2024/4-wheel-drive The reason I want these is so in case the Westcott collars make the...

www.landcruiserforum.com

 

[MtBiker19]

Do you increase LC tire pressures when towing? This helps as well. I run 33psi unloaded, and 39 towing. Im only towing half your weight however.

Yes sir. I do the same- and noticed that 5-6 additional PSI in the rear end helps.

 

[Blue Sky]

I've been looking at the Sumo Springs coil inserts as a potential option. I've been drawn to them because they are no maintenance and easy to install/remove depending on the load.
Only drawback is that I have heard they firm up when it gets below freezing. I would also consider this a light-light/moderate load correction option and your needs may exceed their capacity.

Would love to hear if anyone has experience with these?

Coil SumoSprings | SuperSprings International

Coil Spring Enhancement Made Simple Airless, progressive support that installs inside your factory coils. Find the Right Kit for You Download the Printable Gap Tool to Find the Right Coil SumoSprings for You Smarter than spacers. Simpler than airbags. Stronger support where it counts — right...

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