Radflo makes a direct-fit remote reservoir shock kit for Black Series HQ Series caravans. Installation is a straightforward bolt-on job if you're comfortable working under a suspended caravan — but reservoir mounting and hose routing require careful attention to avoid clearance issues.
What You'll Need
Tools: Floor jack and jack stands, 19mm/22mm/24mm spanners, torque wrench (0–200 Nm), drill with metal bit, Loctite 243, braided hose sleeve, zip ties and P-clamps.
Parts (Radflo kit typically includes): 2× remote reservoir shock absorbers, 2× remote reservoirs (pre-charged with nitrogen), 2× braided reservoir hoses, mounting hardware. Note: reservoir mounting brackets are not typically included.
Step 1: Support the Caravan Correctly
You need the caravan fully unsupported at the suspension — wheels hanging free. Support the chassis, not the axle. On HQ12/15/17/19, use the main chassis rails immediately forward and aft of the suspension crossmember. Never work under a caravan supported only by a floor jack.
Step 2: Remove the Old Shock Absorbers
Lower mounting: locate the 22mm bolt through the bottom clevis, hold clevis with spanner while removing the nut, tap the bolt out with a soft mallet if seized.
Upper mounting: support the shock as you remove the through-bolt — it will drop once released. Set aside old shocks as spares.
Step 3: Check Radflo Shock Length
Verify eye-to-eye length at full compression and full droop matches your OEM shocks. Radflo shocks for HQ Series are typically within 5mm of OEM — confirm before proceeding. Contact Radflo with your model and year if there's a discrepancy.
Step 4: Install the New Shocks
- Insert shock body into upper mount. Start bolt by hand; do not torque yet.
- Align lower clevis with lower shock mount. Insert bolt by hand.
- Route the reservoir hose toward the chassis BEFORE torquing.
- Torque lower bolt first (typically 90–110 Nm for M14 hardware), then upper. Apply Loctite 243 before final torque.
Step 5: Mount the Remote Reservoir
The reservoir must be fixed to the chassis (not the suspension arm), clear of tyre arc at full articulation, protected from direct rock strike, and within the natural hose length arc.
Most installers mount to the inner face of the main chassis rail, forward of the suspension crossmember, using a fabricated or purchased reservoir mount clamp. Use 3mm mild steel plate minimum if fabricating.
Step 6: Route and Secure the Hose
Key rules: no sharp bends (minimum 100mm bend radius), no contact with moving parts (cycle suspension manually to check), no contact with hot components, secure every 300–400mm with P-clamps or zip ties. Add braided protective sleeving where the hose runs near the chassis rail.
Step 7: Final Check
Reservoirs come pre-charged at the correct nitrogen pressure for typical caravan use (usually 150–200 psi). Do not adjust unless Radflo specifies otherwise. Torque all bolts to spec, cycle suspension manually, confirm reservoir is secure, then do a slow test drive before returning to highway speeds.
Radflo remote reservoir shocks for Black Series HQ Series available at RV Parts Giant.