Genuine GM 12556078 Heater Core Inlet Pipe Assembly
Product Overview
The Genuine GM 12556078 is an OEM Heater Core Inlet Pipe or Coolant Hose Assembly. This precision-molded component is a critical part of your vehicle's heating and cooling system, responsible for directing hot engine coolant from the engine into the heater core located inside the dashboard. A properly functioning heater hose is essential for effective cabin heating, defrosting, and overall climate control comfort. Cracks, dry rot, or leaks in this assembly will lead to coolant loss, inadequate cabin heat, potential engine overheating, and interior damage from leaking coolant.
This genuine GM part is engineered to the exact shape, length, and diameter required for your vehicle, guaranteeing a perfect fit, reliable sealing, and long-term durability to restore your climate control system's performance.
Detailed Applications
| Year | Make | Model | Configuration | Positions | Application Notes |
| 2020 | Chevrolet | Express 2500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2020 | Chevrolet | Express 3500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2020 | Chevrolet | Express 4500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2020 | Chevrolet | Express Cargo (Mexico) | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2020 | Chevrolet | Express Pasajeros (Mexico) | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2020 | GMC | Savana 2500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2020 | GMC | Savana 3500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2020 | GMC | Savana 4500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2019 | Chevrolet | Express 2500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2019 | Chevrolet | Express 3500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2019 | Chevrolet | Express 4500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2019 | Chevrolet | Express Cargo (Mexico) | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2019 | Chevrolet | Express Pasajeros (Mexico) | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2019 | Chevrolet | Silverado 2500 HD | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2019 | Chevrolet | Silverado 3500 HD | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2019 | Chevrolet | Suburban | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2019 | Chevrolet | Suburban 3500 HD | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2019 | GMC | Savana 2500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2019 | GMC | Savana 3500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2019 | GMC | Savana 4500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2019 | GMC | Sierra 2500 HD | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2019 | GMC | Sierra 3500 HD | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2018 | Chevrolet | Express 2500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2018 | Chevrolet | Express 3500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2018 | Chevrolet | Express 4500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2018 | Chevrolet | Express Cargo (Mexico) | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2018 | Chevrolet | Express Pasajeros (Mexico) | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2018 | Chevrolet | Silverado 2500 HD | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2018 | Chevrolet | Silverado 3500 (Mexico) | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2018 | Chevrolet | Silverado 3500 HD | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2018 | Chevrolet | Suburban | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2018 | Chevrolet | Suburban 3500 HD | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2018 | GMC | Savana 2500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2018 | GMC | Savana 3500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2018 | GMC | Savana 4500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2018 | GMC | Sierra 2500 HD | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2018 | GMC | Sierra 3500 HD | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2017 | Chevrolet | Express 2500 | V8 294 4.8L | Left | wo/Ceramic Coating |
| 2017 | Chevrolet | Express 2500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2017 | Chevrolet | Express 3500 | V8 294 4.8L | Left | wo/Ceramic Coating |
| 2017 | Chevrolet | Express 3500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2017 | Chevrolet | Express 4500 | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2017 | Chevrolet | Express Cargo (Mexico) | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
| 2017 | Chevrolet | Express Pasajeros (Mexico) | V8 364 6.0L (5967cc) | Left | wo/Ceramic Coating |
Key Features & Benefits
Genuine GM OEM Quality & Fit: Manufactured to General Motors' strict specifications, ensuring an exact replacement that matches the original part's routing, connections, and material properties for a hassle-free installation.
Precision Molded Construction: Made from high-quality, heat-resistant rubber compound that is molded into the specific shape required for your vehicle's engine layout, eliminating stress points and ensuring optimal coolant flow.
Integrated Design for Reliability: Often includes necessary molded bends, pre-installed clamps, or connection fittings, reducing the chance of installation error and preventing future leaks compared to universal hose solutions.
Restores Heating System Performance: Directly addresses failures that cause a lack of heat in the cabin, ensuring reliable defrosting and passenger comfort in cold weather.
Technical Specifications
| Specification Category | Details |
| Part Name | Pipe/Hose Assembly, Heater Inlet |
| Manufacturer | Genuine General Motors (GM) |
| Part Number | 12556078 |
| Condition | New |
| Replaces/Supersedes | This is the current GM part number for this application. |
| Material | Molded Rubber/EPDM |
Vehicle Fitment & Compatibility
This heater hose assembly is designed for a range of popular GM full-size trucks and SUVs equipped with 5.3L and 6.0L Vortec V8 engines.
Primary Compatible Vehicle Applications Include:
| Model | Model Years | Body Style | Notes |
| Chevrolet Silverado 1500 | 2007-2013 | Pickup Truck | With specific engine (e.g., 5.3L V8) |
| GMC Sierra 1500 | 2007-2013 | Pickup Truck | With specific engine (e.g., 5.3L V8) |
| Chevrolet Tahoe | 2007-2014 | SUV | |
| GMC Yukon | 2007-2014 | SUV | |
| Chevrolet Suburban | 2007-2014 | SUV | |
| GMC Yukon XL | 2007-2014 | SUV |
Critical Fitment Note: Cooling system components are highly specific to engine and model year. Always verify fitment using your vehicle's 17-character VIN number before purchase. This part may not fit all trim levels or engine variations within the listed model years.
Installation & Symptoms of Failure
Common Symptoms of a Failing Heater Inlet Hose:
Loss of Cabin Heat: The blower works, but only cool air comes from the vents.
Visible Coolant Leaks: Puddles of orange, green, or red coolant (depending on type) under the front passenger side of the vehicle or steam/smell from the engine bay.
Low Coolant Warning: Frequent need to top up the coolant reservoir with no other obvious leak source.
Swelling, Cracking, or Soft Spots: Visible deterioration upon inspection of the hose.
Installation Advisory:
Replacement involves draining or capturing engine coolant from the system. Exercise caution as the cooling system can be hot and under pressure. Professional installation is recommended to ensure proper bleeding of air from the system after replacement, which is crucial to prevent overheating and restore full heat output.
Frequently Asked Questions
Q: Is this the upper or lower heater hose?
A: The 12556078 is typically the inlet hose that carries hot coolant to the heater core. The return hose (outlet from the heater core) is usually a different part number. Consult a diagram or your VIN for the complete set.
Q: Why choose this molded GM hose over a cheaper universal cut-to-length hose?
A: A universal hose requires precise cutting and may not have the exact bends, which can cause kinking (restricting flow) or stress on connections leading to premature failure. The OEM molded hose ensures perfect fit, optimal flow, and long-term reliability.
Q: My 2010 Chevy Tahoe has no heat. Could this be the problem?
A: A failed or leaking heater inlet hose is a common cause of no heat. However, other issues like a stuck thermostat, clogged heater core, or air in the system can cause similar symptoms. Inspecting this hose for leaks or damage is a good first step in diagnosis.
Call to Actio
Restore your vehicle's heating and cooling system integrity with a genuine, direct-fit GM hose assembly.
Contact us today for competitive pricing, availability, and to perform a definitive VIN-based fitment check for part 12556078. Ensure a reliable repair with OEM quality.
Why Partner with NINGBO JIATIAN AUTOMOBILE PIPE CO., LTD.?
As a specialized factory with extensive experience in automotive piping, we offer distinct advantages to our global clients:
OEM Expertise: We focus on producing high-quality replacement parts that meet original equipment specifications.
Competitive Factory Pricing: Benefit from direct manufacturing costs without intermediary markups.
Complete Quality Control: We maintain full control over our production line, from raw material sourcing to final packaging.
Global Export Support: Experienced in handling international logistics, documentation, and shipping for B2B orders.
Flexible Order Quantities: We cater to both large-volume orders and smaller trial orders to build new business relationships.
Frequently Asked Questions (FAQ)
Q1: Are you a factory or a trading company?
A: We are a manufacturing factory (NINGBO JIATIAN AUTOMOBILE PIPE CO., LTD.) with IATF 16949 certification. This means we produce the parts ourselves, ensuring quality control and competitive pricing.
Q2: Do you offer samples for quality verification?
A: Yes, we encourage potential partners to test our product quality. Samples are available for a modest cost. Contact us to arrange a sample order.
Q3: What is your Minimum Order Quantity (MOQ)?
A: We offer flexible MOQs to support new business. For this standard OE part, the MOQ can be as low as 50 pieces. Custom parts may have different requirements.
Q4: What is your typical lead time for production and shipment?
A: For this specific part, we can often ship sample or small orders within 7-10 days. For larger production runs, the standard lead time is 30-35 days after order confirmation and deposit receipt.
