350Z Rear Shocks, Springs and Mounts: Coupe vs Roadster

56210-CD026 -> K6210-CD02D; 56210-CD725 -> 56210-CD325; E6210-CF40B and E6210-CF40C are separate entries both replaced by E6B10-CF40C; 55020-AM820 -> 55020-AM82A; 55020-AM821 -> 55020-AM82B; 56217-AM000 -> 56217-AM001; 56218-AM000 -> 56218-AG000; 55323-AR000 -> 55323-AR00A. No Coupe-to-Roadster, standard-to-special-suspension, or 350Z-to-G35 supersession is claimed. AM001 and AG000 are application choices, not a claimed supersession chain.

The Z33 rear shock and coil spring are separate assemblies. First identify leakage or lost damping, a broken or sagged spring, shock-mount/bushing noise, or damaged spring seats. Then choose stock height versus lowering and match Coupe/Roadster, year, engine/trim, VIN, and installed tags. Replace shocks or springs in axle pairs. Inspect the bracket, upper/lower shock bushings, seal, distance tube, bump stop/cover, and upper/lower spring seats. Support the rear lower link during service, replace only parts the FSM marks non-reusable, and final-tighten applicable rubber-bushed fasteners under unladen condition with tires on level ground. Check alignment after ride-height changes.

Body-aware verified spring paths are H&R 53050 for Coupe and 53051 for Roadster. TEIN lists Coupe SKP26-C3B00/SKP26-S3B00 and Roadster SKP26-C3B00 with body-specific drop data. RS-R N133D explicitly leaves convertible fitment unconfirmed, so retain it as Coupe-only. KYB seller catalogs conflict between broad 344455 and later 349047 applications; require the current KYB VIN/application catalog before ordering. Bilstein B6 represents the standard-height performance category and B8 is shortened for lowering springs, but no exact Z33 Bilstein number is published without exact manufacturer application evidence. Eibach 6364.140 is omitted because manufacturer-discontinuation evidence conflicts with live seller carts.

US-market 350Z only: 2003-2008 Coupe and 2004-2008 Roadster. Every G35, 2009 Roadster, the separately cataloged *C/VQ35HR/ENTHUSIA/MT branch, other unverified special suspension, and true-rear-coilover conversion are excluded. The rear shock is not a strut and does not carry the separate coil spring. Match body, year/engine/trim, VIN and installed numbers; do not treat shared mounts or seller platform labels as complete-assembly interchange. Replace axle pairs, inspect the complete mount/seat stack, support the lower link safely, follow FSM non-reusable-part and final-tightening instructions, and check alignment after lowering. Seller inventory and prices are dated observations.

Supersede reviewed 24 unique research sources for this guide. 11 also appear above as a seller or official action and are not repeated here; 13 additional citations follow.

Research last verified 2026-07-27.

1. Nicoclub — service manualOpen source
2. Nissan Parts Deal — rear suspensionOpen source
3. Nissan Parts Deal — rear suspensionOpen source
4. Nissan Parts Deal — rear suspensionOpen source
5. Infiniti Parts Deal — rear suspensionOpen source
6. Infiniti Parts Deal — rear suspensionOpen source
7. Tein — us searchOpen source
8. Hrsprings — SuspensionOpen source
9. Hrsprings — technicalOpen source
10. KYB — catalogOpen source
11. KYB — excel gOpen source
12. Workshop bilstein — bilstein b6Open source
13. Workshop bilstein — bilstein b8Open source