Hydro Gear Genuine 72750 Transaxle Service Kit for ZT2800 ZT3100 ZT3200 ZT3400

What It Is

This is a genuine Hydro-Gear service kit (part #72750) designed to rebuild the hydraulic pump and motor in ZT2800, ZT3100, ZT3200, and ZT3400 transaxles. It’s meant for zero-turn mowers that use these specific Hydro-Gear transmissions—common on commercial and high-end residential mowers.

Fitment & Compatibility

Before buying, confirm your mower’s transaxle model (ZT2800, ZT3100, ZT3200, or ZT3400) by checking the ID tag on the transmission housing. This kit fits Hydro-Gear OEM units only—it will not work with aftermarket or generic transaxles. Deck size and mower brand (e.g., John Deere, Cub Cadet, Scag, Toro) are irrelevant if the transmission model matches. Measure the transaxle housing length and bolt pattern if you’re unsure; the kit is specific to these ZT-series units. Do not use it on ZT-5400 or older ZT-2000 series.

Key Things to Know

• Quality: Genuine Hydro-Gear seals, gaskets, and thrust washers—OEM quality, not aftermarket. Expect a long rebuild life if installed correctly.
• Installation difficulty: Moderate to hard. Requires disassembling the transaxle, cleaning, and precise reassembly. You’ll need a bearing puller, seal driver, and torque wrench. Not a beginner job.
• Common gotchas: The kit does not include oil—you must buy Hydro-Gear 20W-50 or 15W-50 separately. Also, check for worn bearings or shafts before reassembly; the kit only replaces seals and gaskets, not internal wear parts.
• Cost vs. replacement: At $96, this kit is cheaper than a new transaxle ($300+), but only if the unit isn’t damaged internally.

Should You Buy It

Buy this if you have a ZT2800–ZT3400 transmission that’s leaking or losing power and you’re comfortable with a full teardown. Skip it if you’re not experienced with hydrostatic repairs or if the transaxle has metal shavings in the oil—that indicates internal damage beyond a seal kit.