Hyster S120 Lift Cylinder Rebuild in Ames, Iowa
If your Hyster S120 is drifting down at the top of the mast, leaking a slow puddle under the truck overnight, or just plain won’t lift a full load anymore, chances are you’re looking at a Hyster S120 lift cylinder rebuild. We see this on S120s that have been running two or three shifts a day at grain co-ops, distribution warehouses, and construction yards all over central Iowa. The bore wears, the seals harden, and eventually the cylinder can’t hold pressure under load.
We’ve rebuilt a lot of these lift cylinders on the bench here at 210 Freel Dr, and the pattern is pretty consistent: scoring on the barrel wall, a chewed-up rod seal, and a piston seal that’s lost its lip. A proper Hyster S120 lift cylinder rebuild means we’re not just swapping a seal kit and hoping — we’re checking bore diameter, rod straightness, and the condition of the gland before anything goes back together.
How We Do a Hyster S120 Lift Cylinder Rebuild
Every Hyster S120 lift cylinder rebuild we run through the shop follows the same basic sequence, whether the truck comes to us or we come to it:
- Pull the cylinder off the mast and drain the residual hydraulic fluid
- Disassemble the cylinder and inspect the bore for scoring, pitting, or out-of-round wear
- Hone or resurface the bore if it’s within tolerance — replace the barrel if it’s not
- Install new head seal, piston seal, U-seals, and wiper seal (sized to spec, not guessed at)
- Reassemble, reinstall on the mast, and bleed the system before it goes back to work
We stock common seal sizes for lift cylinders in this class — head seals, piston seals, U-seal sets, and wiper seals — so most Hyster S120 lift cylinder rebuild jobs don’t sit around waiting on parts from three states away. If you’re outside Ames, our hydraulic cylinder rebuild coverage across Iowa means we can usually get to your yard within a day or two for mileage plus the rebuild.
Common Failure Symptoms on the S120 Lift Cylinder
Most calls we get about a Hyster S120 lift cylinder rebuild start with one of these complaints:
- Slow drift down under load: usually the piston seal has lost its seal against the bore, letting fluid bypass internally.
- Visible leak at the rod: the rod seal or wiper seal has hardened or torn, letting fluid weep out past the gland.
- Jerky or hesitant lift: air in the system after a partial seal failure, or scoring in the bore causing uneven fluid flow.
- Won’t lift full rated capacity: internal bypass is severe enough that the cylinder can’t build or hold pressure.
- Loud bang or sudden drop: a blown seal that let go all at once — this is the point where we’re doing full disassembly, not just a top-up.
One thing we tell every customer up front: it’s really common for the other lift cylinder on a dual-cylinder S120 mast to blow out shortly after we rebuild the first one. The second cylinder has been running the same hours under the same load, and once one goes, the other is usually right behind it. We’ll flag this during inspection if we see early wear starting on the mate.
How Much Does a Hyster S120 Lift Cylinder Rebuild Cost
Pricing on a Hyster S120 lift cylinder rebuild depends on how bad the bore is and whether we’re rebuilding one cylinder or two. Rough ranges we typically see:
- Standard rebuild (seals, honing, reinstall, bleed): $600–$950 per cylinder
- If scoring is too deep to hone and the barrel needs replacing: add roughly $300–$800 depending on cylinder size and availability
- Shop mileage for jobs within 30–40 miles of Ames: typically $40–$75 round trip, folded into most quotes
- Lock cable or lock cylinder replacement done at the same time (common on masts with a locking feature): add $145–$300
We give a firm number after we’ve had the cylinder open on the bench — not before. Guessing on seal condition over the phone doesn’t do anyone favors. For a broader breakdown of what drives these numbers across cylinder types, our hydraulic cylinder rebuild cost guide covers the same logic we use here.
We also handle lift and tilt cylinders on other equipment beyond forklifts — if you’ve got an excavator boom cylinder acting up, our excavator cylinder rebuild work out of Boone follows the same bench process. And if the mast is fine but the drive train is what’s failing on your lift truck, take a look at our final drive rebuild service too.
If your S120 is dropping under load or leaking at the rod, don’t wait for it to fail on a full pallet. Call us at 515-292-2599 and we’ll walk through what a Hyster S120 lift cylinder rebuild will run for your specific truck, and get it scheduled at the bench or out at your yard.
Frequently Asked Questions
How long does a Hyster S120 lift cylinder rebuild take?
Most single-cylinder rebuilds take one to two days once the cylinder is on our bench, depending on whether the bore needs honing or a full barrel replacement. We’ll give you a firm timeline once we’ve inspected it.
Can you rebuild the cylinder on-site or does it have to come to your shop?
We usually pull the cylinder and take it back to 210 Freel Dr for the rebuild itself, since honing and precise seal work need bench conditions. Removal and reinstall can often happen at your location.
Why did my other lift cylinder fail right after you rebuilt the first one?
Dual lift cylinders on the S120 mast run the same hours under the same load. Once one shows internal wear, the other is often close behind — we’ll flag early signs during inspection so it’s not a surprise.
Is it cheaper to rebuild or replace the Hyster S120 lift cylinder?
Rebuilding is usually cheaper if the bore is within tolerance for honing. If scoring is too deep, a new cylinder can add $300–$800 to the job, and at that point replacement sometimes makes more sense — we’ll tell you honestly which way the numbers point.
Do you carry seal kits for the Hyster S120 lift cylinder in stock?
We stock common head seals, piston seals, U-seal sets, and wiper seals for lift cylinders in this size range, so most Hyster S120 lift cylinder rebuild jobs don’t get held up waiting on parts.
Written by Josiah Ragsdale, Ames Hydraulics