Exmark 135-2307 Hydro Service Kit Quest QZS Radius E S X Series ZT-2200-ZT-2800 Premium Oil

What It Is

The Exmark 135-2307 Hydro Service Kit is an OEM maintenance kit for Exmark Quest, QZS, Radius, E, S, and X Series zero-turn mowers equipped with ZT-2200 or ZT-2800 hydrostatic transmissions. It includes premium 20W-50 oil, filters, and seals needed to service both drive pumps.

Fitment & Compatibility

Check your model: This kit fits Exmark Quest, QZS, Radius, E, S, and X Series mowers with Hydro-Gear ZT-2200 or ZT-2800 transmissions only. Confirm your transmission model by looking at the metal tag on the pump body. Does not fit ZT-3100, ZT-3400, or older ZT series. Deck size (42", 48", 50", 52", 60") is not a factor—only transmission model matters. OEM part, not aftermarket. If you have a Toro, Scag, or other brand with the same transmission, this kit is not cross-compatible—Exmark uses a specific oil blend.

Key Things to Know

• Installation difficulty: Moderate. Requires draining old oil, removing filters, and bleeding air from the system. A service manual or YouTube walkthrough is recommended for first-timers.
• Oil volume: Kit contains enough oil for two ZT-2200 or ZT-2800 pumps (roughly 76 oz total). Do not overfill—check level with transmission in neutral and engine off.
• Common gotcha: The kit includes new o-rings for the filter heads. Replace them every time to prevent leaks. Do not reuse old o-rings.
• Service interval: Exmark recommends this service every 400 hours or annually, whichever comes first. Skipping it can cause premature pump wear.

Should You Buy It

If you own an Exmark zero-turn with ZT-2200/2800 transmissions and want to keep it running reliably, this kit is a no-brainer. It’s priced competitively compared to buying oil and filters separately, and it’s exactly what Exmark specs. Not for other brands or transmission models—stick with OEM for warranty and performance.