Icon Suspension - Very rough ride

2016 TRD OR DC SB, Stage 2 Icon, Total Chaos UCA's

I'm having a hard time accepting the ride since lifting my truck. I've been searching for about a week and haven't really hit a similar situation. So I'm posting for input / advice.

I bought the truck new, never been off road. @ 22,500 miles, I installed an Icon Stage 2 suspension and Total Chaos UCA's. Truck was aligned afterwards. I had the driver's side CV axle vibration and I fixed that using the East Coast Gear Supply bushing. That problem was gone and the truck rode great. About 2,000 miles later on the new suspension, I started to notice that the rear of the truck felt like it was shaking driving down the highway.

This shaking happens on highways, back roads, and city streets at all speeds. I feel it in the lower seat back and the (empty) passenger seat shakes pretty bad. It seems like it is coming from the rear of the truck like the axle is jumping up and down really fast.

I had the alignment done again and it is still doing it. Yesterday, I installed the stock tires and no change. I installed a diff drop, no change. I installed a carrier bearing drop, no change.

In my mind, it seems like the rear axle is jumping up and down very fast, excited by minor bumps in the road. Sometimes it is hardly noticeable and other times it is unbearable. I hear no weird sounds coming from the suspension. U-bolt torque has been verified.

The front seems tight and rides really good. I just can't accept that my ride quality is the same as everyone else that loves this setup.

So far, I am sure it is not related to the following:

-alignment
-aftermarket tires / wheels
-carrier bearing drop
-diff drop
-u-bolt torque

I want to try different leaf springs (Alcan) but that's alot of money for it not to change anything. Could the rear shocks be the culprit?


Need some help here. Not sure what to do

 

take a pic of your shocks, so we can see the pre-load .. that's probably your problem

 

If you mean the front shocks, the right side is at the factory setting and the left has been turned 6 rounds to correct for the lean. Would you think the front shock settings could affect the ride in the rear? I am open to all suggestions, but I am sure my coils aren't cranked too high.

 

UPDATE: New Bilstein 5100 rear shocks going on tomorrow. Probably got my hopes up for nothing. As for now, drink beer and hope for minimal hurricane destruction.

 

curious if the new rear shocks fixed your issue.

 

Put a gopro or video recording instrument under your truck and see what the rear axle is doing when it feels bouncy, post the video here.

 

You do realize that ICON shocks are rebuildable/re valveable right? If the preload on the front isn't the issue(it probably is) then you can revalve the rear shocks. Call whoever you bought them from to get them revalved.

Putting new shocks on is a waste of money and likely won't solve anything. Post a picture of the front suspension.

 

I have had this problem in my older toyota trucks and it was usually a bad ujoint. Only some of mine made noise. If the new billys didnt help, them go hit up all your zerks and see if anything changes.

And I know you dropped the CB but did you check it for too much play?

 

Was the overload leaf removed when the AAL was installed? If not, that'll make for a pretty rough rear ride.

 

How much higher than your stock height did you adjust the Icons up?

 

What pressure do you have the tires set at?

 

89psi perhaps on one rear tire? haha

I bought a land cruiser once, had 70 psi in each of the 31" tires. Unbelievable!!

 

I have been out of internet range for a while. Wow! Thanks for all the interest in helping.
1. the new shocks are not long enough at full droop. I didn't install them since I knew they would be damaged soon after.
2. U joints have all been greased and carrier bearing support is tight.
3. I don't think the front preload is the culprit because the passenger side is at the stock height (I never turned it at all), and the driver's side has been turned 6 rounds to correct for some of the taco lean.
4. The overload springs are not installed.
5. Tire pressure is set at 32 psi @ 80 degrees. I have swapped back and fourth from my new E load rated tires to the stock tires and the truck still shakes.

Thanks again for all the help.

 

ANOTHER reason WHY ....

I love the looks of a lift but am reluctant to add one

 

Did

Did you end up figuring this out?? I've got 5100s, OME 888s, Dakars, and LR UCA and am running 185/75/17 on TRD Pro wheels. My rear end hops a bit as well, but it's seemed to settle down as the leaf springs break in (Dakars seem to run stiff at first, and I suspect this has been the culprit for me). Very curious if you ever found the root of the problem.

 

I quit looking into the source of the problem, always wondering if it was related to the new frame design. I sold the truck. NOT BECAUSE OF THIS PROBLEM. I just needed more room and a bigger truck.

 

thanks man!