The Genie 1260900GT DEF Coolant Valve is a genuine OEM component designed for Genie GTH-series telehandlers equipped with the TCD3.6 T4F engine. Sourced directly through Genie's OEM supply chain, this valve is built to the exact specification required for proper DEF system operation on GTH-844, GTH-1056, GTH-1256, GTH-1044, GTH-1244, and GTH-1544 telehandlers. Cross-reference part number 1260900GT against your machine's parts manual to confirm fitment before ordering. This is the correct OEM part to restore full emissions and fluid management system function on affected machines.
Key Features
- OEM-Spec DEF System Integrity — Built to Genie's exact material and flow tolerances for the TCD3.6 T4F engine's DEF coolant circuit, ensuring the valve opens and closes at the correct thermal thresholds.
- Direct-Fit Replacement — Engineered to match the original valve's port sizing, connector configuration, and mounting interface for a straightforward swap with no rework.
- Broad GTH Telehandler Coverage — Fits six GTH-series models including the GTH-844, GTH-1056, GTH-1256, GTH-1044, GTH-1244, and GTH-1544.
- Emissions System Performance — A correctly functioning DEF coolant valve keeps the selective catalytic reduction (SCR) system operating within its designed temperature range, helping the machine maintain Tier 4 Final compliance under working loads.
- Regulatory Compliance Assurance — On Tier 4 Final machines, a failed or bypassed DEF system component can trigger fault codes, derate engine output, or prevent the machine from starting — making this valve a critical emissions and operability part.
The DEF coolant valve regulates the flow of engine coolant through the diesel exhaust fluid (DEF) heating circuit. On cold starts or in low-temperature conditions, engine coolant is routed through the DEF lines and tank to prevent the fluid from freezing and to bring it up to operating temperature quickly enough for the SCR aftertreatment system to function correctly. When this valve fails, DEF may not reach the required temperature in time, causing the SCR system to operate outside its effective range — which can result in increased NOx emissions, fault codes, engine derating, or an inability to restart the machine once it shuts down. Replacing a faulty valve with the correct OEM part restores proper thermal management to the DEF circuit and keeps the telehandler running within Tier 4 Final emissions standards.
Part Details
| Part Number | 1260900GT |
|---|---|
| Brand | Genie |
| Part Type | Genuine OEM |
| Description | DEF Coolant Valve, TCD3.6, T4F |
Compatibility & Fitment
| Name | Model |
|---|---|
| GTH-844 | GTH-844 |
| GTH-1056 | GTH-1056 |
| GTH-1256 | GTH-1256 |
| GTH-1044 | GTH-1044 |
| GTH-1244 | GTH-1244 |
| GTH-1544 | GTH-1544 |
Verify Before You Order
Fitment is machine-number and revision-specific; always confirm your model and serial number against the fitment list.
Why Buy From DHS Equipment
Every part is verified against the manufacturer's part number before it ships, so what you order is what arrives. We carry parts from leading OEM brands and our own DHS Quality Parts line of professional aftermarket components. Need help finding the right part? Our team is available to confirm compatibility whenever you need it. Orders are processed fast to keep your jobs on track. We don't just sell parts. We keep you jobsite ready.
Questions? Contact our team at [email protected] or 866-611-9369 — DHS Equipment is here to help you maintain peak performance.
