Overview
Hydro-Gear ZJ-GCEE-SB5A-1MXX is a genuine Hydro-Gear ZT-3100 hydrostatic transaxle. The ZT-3100 is Hydro-Gear's entry-level commercial-grade integrated transaxle.
Order by the full model number on the Hydro-Gear label (ZJ-GCEE-SB5A-1MXX). Hydro-Gear builds each model to an OEM specification and advises against substituting a different model, so match every character; zero-turns use a left and a right unit — check which side you need.
More on this series: Hydro-Gear ZT-3100 guide · Shop all ZT-3100 & ZT-3200 transaxles
Specifications
| Brand | Hydro-Gear (genuine) |
|---|---|
| Model / part number | ZJ-GCEE-SB5A-1MXX |
| Series | ZT-3100 |
| Type | Hydrostatic Transaxle |
| Pump / motor displacement | 10 cc pump, 16 cc motor (series spec) |
| Input speed | 3600 rpm max (no load), 1800 rpm min (series spec) |
| Output torque (up to) | 350 lb-ft (474 Nm) (series spec) |
| Speed (up to) | 9 mph (series spec) |
| Max machine weight | 1200 lb (544 kg) gross vehicle weight (series spec) |
| Axle | 1.0 in; tapered, 4-bolt or 5-bolt flange (series spec) |
| Unit weight | 32.5 lb (14.7 kg) (series spec) |
| Reduction | 20.69:1 (ZJ prefix, series spec) |
| Fluid | 20W50 engine oil (series spec) |
| Filter | External spin-on, Hydro-Gear 52114 |
Service notes
- Oil and filter: 20W50 engine oil and Hydro-Gear filter 52114. First change at 75–100 hours, then every 400 hours.
- Capacity is about 2 qt per transaxle (56.6–71.9 fl oz depending on configuration), excluding the expansion tank and hose.
- After installing, purge air from the system following Hydro-Gear's procedure: wheels off the ground, cycle forward/reverse 5–6 times with the bypass open, then 5–6 times closed, and top up the oil.
Shipping
- Free shipping (lower 48). Ships from distributor stock.
Frequently asked questions
Where do I find my Hydro-Gear model number?
On the Hydro-Gear label on the unit (on the transaxle). Current numbers look like ZH-JPBB-SF7B-2XLX. See how to find your Hydro-Gear part number.
Can I use a different model that looks the same?
Hydro-Gear strongly discourages using any model not originally specified by the mower maker; similar-looking units can differ internally. Order the exact number on your label.
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Hydro-Gear · ZJ-GCEE-SB5A-1MXX
Hydro-Gear ZJ-GCEE-SB5A-1MXX ZT-3100 Hydrostatic Transaxle
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