I am a little stumped... I am hoping some of yall that have more knowledge on the subject than I, have some info that might help me troubleshoot this. From what I gather from searching for this issue, there are others that have had similar issues. But I don't recall seeing a definitive answer on the root cause. If we can figure this one out, hopefully it will help others when/if they have this issue. I will try to be as descriptive as possible for any future people who may read this trying to solve a similar problem (sorry if its a bit long winded)!
My 2019 with 36,000 miles (maybe 300 off road miles mostly beaches), it seems like the shocks are stuck at full stiffness, and got slowly worse over time. Since it's no longer in warranty, I am trying see if I can determine the problem versus just dropping it off at the dealer and letting them run up the bill.
I remember the ride being incredibly smooth when the truck was new, and aiming for potholes just to grin at how good the suspension was. When the truck had about 6k miles, I put Eibachs and +3HD Deavers on, the suspension was notably more stiff, but I don't recall it riding like a dump truck. Almost 30k miles later, getting tired of the harshness during on road use, I put the stock/OEM front springs back on, and replaced the leaf springs with +2SD Deavers. While the suspension softened up a little, it is pretty apparent its no where as smooth as it was when new. Small pot holes and speed bumps that I would have barely noticed when new, now jar the hell out of the truck.
In hindsight, I guess its a little like putting a frog in boiling water vs slowly heating it up. Its obvious to me now that a majority of the harshness of the ride I was getting annoyed with may not have been related to the Eibachs and HD Deavers.
From what I understand, the common areas for the system to fail and cause full stiffness would be the VDM module, wiring harness, solenoids, or the shocks themselves.
1) With Forscan, I checked for any DTCs, none.
2) Ran the ride height recalibration, no difference (tried several times).
3) Reset the VDM with the factory as built config values, no difference.
4) Re-ran the ride height recalibration after resetting the config values, no difference.
5) No matter the mode I put the truck in, sport, normal, baja, the suspension feels the same. I recall there being a pretty noticeable change when the truck was new.
After the ride height recalibration, front ride height sensors read 0mm +- 1mm, rear values read 0mm (no sensors on rear).
I am not sure if this is expected, when monitoring the live data from the VDM with forscan while on flat level pavement, I notice that no matter the mode I put the truck in, values always stay about the same. About 1.6 +- 0.05 amps, and 50% +- 5% duty cycle.
I don't think its the wiring harness, the resistance that the VDM is measuring according to Forscan is 5 ohms to each shock. Ran the self test in forscan for the VDM. No DTCs. If I unplug a shock, it will throw an error.
I don't hear any noticeable humming/noises coming from the solenoids. But I don't know how to rule these out as the cause.
I understand that at 36k miles I am kind of close to the specification for rebuilding the shocks, but then you have people on this forum reporting like 75k miles and barely noticing a difference, and if they do, its a softer ride, not a more harsh ride...
I am kind of at a loss to further narrow down the cause of the harsh ride.
