So I've waited some time before writing this review. I installed the springs to test them out for a couple months under normal driving before we planned on towing our 5th wheel.

I installed these on my 2020 SRW 3500 Sierra Denali. I tow a 42' Jayco eagle 5th wheel which has a dry hitch weight of 2,420lbs and dry weight of 12,830lbs. Obviously loaded weights are more, and the truck was more than fine pulling our trailer as is, however I felt it could use a little help out back to stiffen things up a bit, and with the rear dropping about 3" when loaded. I choose these to try as an alternative to air bags. I had tried Timbrens on a previous truck and hated them. Way too stiff and very harsh unloaded over dips and bumps, way to stiff while loaded. I had air bags on a previous truck and although they were great, I had to air them up every time I towed. Wanted something that I could just hook up and go.

Install was very straight forward. Instructions were decent. I will say, pay attention to the direction you install the springs as you can 180 them.

Driving unloaded. Overall I'm pleased with them. Most of the time you don't know that they are there. You can feel them touch slightly over large bumps and large dips in the road. When they engage in these situations, it isn't harsh by any means. Night and day better than the Timbrens I had in the past. I think my biggest gripe with these, is that you can hear them rattle some over bumps and dips when you have the windows down. Windows up, you cannot hear it. I will say that now I've towed my trailer with them, the noise level has gone WAY down. I don't know if they have "settled" in some now that they have had load on them. Could be that outside temps are lower now that it's fall, I don't know.

Loaded. Very happy with them. Rear of the truck sits about 1.25" higher loaded now. I will have to lower the front of my trailer some. It was slightly nose high before I installed these, and I did notice some bucking now that I believe is related to the trailer being nose-high. The truck feels way more planted over bumps and dips. Honestly feels much like having air bags. Just way more solid and stable. They made quite a difference.

Pros: Easy install. Not a complicated system, just hook up and go. No rubber or lines to worry about going bad with age and while on the road. Helps level the truck some. Good ride quality unloaded. Minimal weight added to the vehicle. Maintenance free. More cost effective than air bags, especially when comparing to an on board air setup.

Cons: Some noise unloaded over bumps. I feel like some pads/insulators could have been included in the design much like the factory leaf pack to avoid this. May try to come up with something, but like mentioned above, after I've had load on them, then noise seems "almost" gone, will have to keep monitoring. No adjustability with this kit in terms of rear height or stiffness. 3218536

I have a 2021 F-350 Tremor and originally there were issues of fitment that were apparently some subtleties from the non-Tremor editions where the curvature of the factory helper spring did not match the curvature of the Hellwig helper springs. I contacted Hellwig and as well as etrailer to inform them of the issues. Although etrailer was more than willing to step in and provide a refund, I was actually able to work directly with Kevin at Hellwig and through some detailed photos of the issue and some collaboration on the phone, they actually manufactured a set of helper springs that fit perfectly! Thank you Kevin at Hellwig and etrailer for both of your exemplary customer service!! 3469120

They worked great while pulling a 40' gooseneck trailer. 3373287

Helper springs are doing the job, I did torque U bolts to spec, however the helper springs are sliding sideways a bit and not staying in the same position as stock springs 3620037

This is without a doubt the best modification for truck bed campers. Installed it on my F350 Dually with out removing the wheels. Took less than an hour. Handling and sway control was incredible. Does not affect unloaded handling. 3239542

Great product from HellWig, easy install on my 2016 Ford F-350 dually and helps carry my Lance truck camper very well.
Hats off to Fred E. & etrailer for getting the order together and shipping fast. 3509949

Good product. Made strong, simple and easy installation. 3527217

product is what was expected.
Lakysha very helpful over the phone and received product when she said I would.
My second product order from e-trailer and will not be my last
EXCELLENT customer service 3456054

Fast service. 3592052

Mostly ,not enough lift. My toy hauler is heavy and my f250 still squats 3388211

Outstanding product and an easy add on. With my heavy truck camper this made all the difference. No more Porpoising or head bobbing on bumps and really levels out the camper. I use much less airbag pressure now and the suspension is more active. This also fixed the loud squeaking I was experiencing on one side. It's incredible what a difference! No need now for expensive major leaf spring work. 3318121

Your company runs a tight ship thank you very much 3497856

As usual, etrailer does a fantastic job! 3395952

They work amazing 3380301

Very easy install, will update after miles and weight are added on. 3252457

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