I've swapped-out my D4's a couple of times. The last time I removed the front inner guards to get easier access to the top nuts and air lines but the extra time to R&R the liners made it not worthwhile. The rears are easy enough with the liners in place.
If you want firmer shocks than D3s then get D4s although I don't know if D4s are available except through LR. I replaced my D4 orginals with D3s ex LR and when those wore out I fitted D3 Delphi ex UK although I feel that their valving isn't as good as the LR D3s were.
MY21.5 L405 D350 Vogue SE with 19s. Produce LLAMS for LR/RR, Jeep GC/Dodge Ram
VK2HFG and APRS W1 digi, RTK base station using LoRa
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