Order directly from our stock by selecting "Core exchange, order from our inventory" above.  Listed price includes $600 core deposit.

On cylinders with travel sensors attached, Top Hydraulics rebuilds the cylinders only, not the travel sensor(s). You are welcome to send us your cylinders with sensors attached, but the sensors do not get serviced.

Unfortunately, the seals in the hydraulic cylinders deteriorate with time, and the service life of the original seals can be less than ten years in warm climates. This decay is a chemical reaction that gets accelerated by high temperatures or by additives to the hydraulic fluid. Each cylinder has four static seals that seal the front and rear caps and the hydraulic line ports, plus a rod seal that seals the moving metal rod to the cylinder body, plus a piston seal that prevents internal leaks and transfers the hydraulic pressure from the pump into movement of the cylinder's piston.

Typically, you will see your hydraulic cylinders leaking first at the bottom, where you wouldn't expect it. The first thought will be that an o-ring on the hydraulic line must be defective. It is actually the first sign that all seals need to be replaced. Seal replacement is absolutely not a DIY job, because the cylinders are crimped together. It requires special machinery to disassemble and reassemble these cylinders, plus all four internal seals have special shapes and sizes. The internal seals are not available to the public. Only the port seals (sealing the hydraulic lines to the cylinder body) are standard o-rings, but they do not normally fail unless they get damaged upon hydraulic line installation.

Top Hydraulics manufactures its own internal seals for your Infiniti G37 hydraulic cylinders. They are a clear improvement over the original seals both in material and geometry. For example, the tiny flat rod seals get replaced with much larger cup seals, which will stay elastic much longer and are more forgiving towards scratches or impurities on the polished cylinder rods.

In the extremely rare cases that a cylinder shaft got rusty or damaged by a tool during a futile DIY repair attempt, Top Hydraulics can replace the shaft with a hardened stainless steel version from its own production (for a surcharge).

You send us the cylinder(s) you need to have upgraded, and we will turn them around in 1-3 days. Using the best seals available, far exceeding OEM quality, and making your old cylinders truly better than new OEM cylinders.