BMW Coolant Hose Kit (7 Hoses) - 128i, 328i, 325i/xi, 330i/xi - N51 Engine, Automatic

If you're chasing a coolant leak, a soft heater hose, or a check-engine light tied to overheating on an E82 1 Series or E9x 3 Series BMW, this BMW coolant hose kit replaces every hose in the system at once instead of chasing one cracked section at a time. It's a direct-fit, 7-piece kit built for the N51 engine with automatic transmission, and it covers the exact routing BMW used from the water pump all the way to the expansion tank — so you're not stuck ordering three separate hoses over the next two winters as the rest of the rubber gives out.

Which BMWs This Fits

This kit is engineered specifically for BMW models equipped with the N51 engine and automatic transmission — that qualifier matters, since the hose routing and the transmission oil cooler line differ on manual cars and on the N52/N54 engines. Confirmed fitment:

• BMW 128i (2008-2013)
• BMW 325i (2006)
• BMW 325xi (2006)
• BMW 328i (2007-2011)
• BMW 328i Convertible (2012-2013)
• BMW 328i Coupe (2012-2013)
• BMW 328i xDrive (2009-2012)
• BMW 328i xDrive Coupe (2013)
• BMW 328xi (2007-2008)
• BMW 330i (2006)
• BMW 330xi (2006)

Before you buy, it's worth double-checking your own VIN or engine code against these years, since BMW ran overlapping engine options across the same model names during this era. If you're not sure which hoses your specific car needs, our request a part page is the fastest way to get a second opinion before you order.

What's In the Box — All 7 Hoses

This is a complete cooling circuit kit, not a single hose. You get:

• 1x Water Hose — Water Pump to Engine Inlet
• 1x Water Hose — Thermostat Housing to Water Pump
• 1x Water Hose — Cylinder Head to Thermostat Housing (heavy duty fitting)
• 1x Water Hose — Radiator to Auto Trans Oil Cooler
• 1x Upper Radiator Hose — Engine to Radiator
• 1x Lower Radiator Hose (with temperature sensor fitting)
• 1x Water Hose — Upper Radiator Hose to Expansion Tank / Vent Hose

These cross-reference to OE numbers 17127564480, 11537516414, and 11537545665, so if you're comparing against what's currently on the car, or against a dealer quote, that's what to match against.

Why Replace the Whole Set Instead of One Hose

Coolant hoses on these cars tend to age together — if one is cracked or weeping at a clamp, the rest are usually not far behind, since they've all been through the same heat cycles for the same number of years. That's really the case for a full BMW coolant hose kit rather than a one-off replacement: you do the job once, on your schedule, instead of pulling the intake manifold or fighting for access to the same spot again in six months.

The hoses themselves are molded from a heat-resistant, ozone-resistant rubber compound meant to hold up under the same underhood conditions as the original equipment, and they're built as direct replacements — same routing, same fittings, so there's no cutting, splicing, or improvising brackets. The lower radiator hose keeps the factory temperature sensor fitting, and the reinforced walls resist vacuum collapse under load, which is the failure mode that tends to show up as a hose that looks fine cold but pinches shut once the system's hot and the water pump is pulling against it.

None of this is exotic engineering — coolant hoses are a fairly simple part of how a car sheds engine heat — but simple parts still fail, and when they do, they tend to fail at the worst time. If you want the background on how these systems work end to end, Wikipedia's overview of the internal combustion engine cooling system is a decent, non-commercial explainer of what each hose in this kit is actually doing.

Specifications

• Item Type: Hose (coolant/water hose kit, 7 pieces)
• Condition: Brand New
• Material: Rubber
• Warranty: 2 Year Warranty
• Fitment Type: Direct Replacement
• Placement on Vehicle: Front, Rear, Left, Right
• OE/Reference Numbers: 17127564480, 11537516414, 11537545665
• Engine/Transmission Fitment: N51 engine, automatic transmission

Installation Notes

Because every hose is a direct replacement, installation is mostly a matter of draining the system, working through the routing one hose at a time, and torquing the clamps back to spec — most home mechanics comfortable with basic cooling system work can get through the full kit in an afternoon. That said, a couple of these hoses sit close to the intake and accessory brackets, so give yourself more time than you think you'll need the first time through, and have a catch pan ready since you'll be draining and refilling coolant. Always let the engine cool completely before opening the system.

Once it's installed, bleed the system properly and keep an eye on the temperature gauge over the first few drive cycles — that's true of any cooling system job, not just this one, and it's the easiest way to catch a loose clamp before it becomes a leak on the highway.

Warranty, Shipping, and Support

This kit carries a 2-year warranty against manufacturing defects, and full details are on our warranty page. If you're weighing this against another part, or just want to confirm compatibility one more time before checkout, our FAQ covers the questions we get most often about fitment and returns. For questions we haven't answered there, reach out through our contact page and a real person will get back to you.

Once your order ships, you can follow it on our order tracking page, and our shipping page has current timelines and policies. This hose kit lives in our cooling system parts collection alongside radiators, water pumps, and thermostats for other applications, and if you're working on more than one system on the same car, our full BMW parts collection is worth a browse while you're at it.

Bottom line: if your 1 Series or 3 Series N51 is due for cooling system work, this BMW coolant hose kit gets all seven hoses done in one order, with OE-matching fitment and a warranty behind it, so you're not back under the hood chasing the next hose that lets go.