EQ Systems SM 30 Hydraulic Cylinder | Part 1135EQ | 30" Stroke | 5" SM Commercial Series

Replace a leaking, pressure-losing, or non-holding SM series 30" stroke hydraulic cylinder in your EQ Systems tube-in-tube jack with the EQ Systems SM 30 Cylinder (Part 1135EQ). The cylinder is the working part inside the 5" square outer tube — outer tube, brackets and foot stay on the trailer; only the cylinder gets swapped. Extended-reach option for chassis needing extra stroke. Available at The RV Surplus.

Fitment critical: Verify cylinder configuration before ordering. Call EQ Systems at 800-846-9659.

⭐ 30" Stroke SM Series Replacement — 25,000 lbs

• Fits SM series tube-in-tube jacks — heavy-duty commercial (25,000 lbs per jack)
• 30" stroke, 3.5" cylinder bore — extended reach
• For jacks with a 5" square outer tube 38¼" long

⭐ Identifying the Right Cylinder

Cylinders are identified by the outer tube of the jack, not by the bracket. Jacks of the same size can carry different brackets and still take the same cylinder. Measure the square dimension of the outer tube and its length:

• 5" square × 24" long = 16" stroke (Part 1573)
• 5" square × 28" long = 20" stroke (Part 1104)
• 5" square × 32" long = 24" stroke (Part 1407)
• 5" square × 38¼" long = 30" stroke SM (this cylinder, 1135)
• 5" square × 43¾" long = 36" stroke (Part 1406)
• 5" square × 75⅞" long = 60" stroke (Part 2891)

⭐ Check Your Fittings — NPTF vs SAE

Older cylinders were built with NPTF fittings; current production uses SAE. Quick check:

• SAE: no threads exposed between the cylinder body and the hex
• NPTF: threads exposed between the cylinder body and the hex

This cylinder has shipped with both types over its life. If your jack has NPTF fittings, call EQ Systems at 800-846-9659 before ordering so the correct replacement fittings go out with the cylinder.

Documents

• Hydraulic Cylinder Identification for Tube-in-Tube Jacks (PDF)
• EQ Systems Hydraulic Jack Options, Commercial Range (PDF)
• Required Maintenance Items for EQ Hydraulic Jacks & Slide Systems (PDF)

Other Cylinders

• SM 16 Cylinder (1573EQ) — 16" stroke, 5" tube
• SM 20 Cylinder (1104) — 20" stroke, 5" tube
• AM 24 Cylinder (1179EQ) — smaller AM series (4" tube)
• CT 20 Cylinder (1178) — CT series

90-Day Warranty

Backed by EQ Systems' 90-day replacement part warranty. Check documentation for full terms.

Specifications

• Brand: EQ Systems
• Model: SM 30 Cylinder
• SKU: 1135EQ
• Jack Series: SM tube-in-tube (heavy-duty commercial)
• Stroke: 30" (extended reach)
• Cylinder Bore: 3.5"
• Fits Outer Tube: 5" square × 38¼" long
• Jack Capacity: 25,000 lbs
• Fittings: NPTF or SAE (verify before ordering)
• Warranty: 90-day replacement part warranty