Fiat 500X Radiator: Specs, Fitment & Common Faults

On the 500X, a cracking plastic thermostat housing spigot is genuinely the single most common cause of coolant leaks.

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OEM Part Number: 52009105 (as quoted in catalogue listings — confirm via VIN) — aftermarket radiators Nissens 606447 / Valeo 701760

Accuracy note: Covers the Fiat 500X (2015-) as listed in the UK aftermarket catalogues. Radiators are sold by engine, gearbox and air-conditioning fitment, and one model usually has two or three different cores — a thicker core for diesels and automatics, a thinner one for small petrols — with different hose positions, so a radiator for the wrong engine will not connect up. The references below are UK aftermarket listings whose fitment lists name this generation, labelled by brand with the core size in mm; genuine numbers are those quoted against the listing. Check your engine code and whether the car has air conditioning against your VIN, and replace the coolant and bleed the system after fitting.

Radiators (aftermarket)	Nissens 606447 (620 x 389 x 16 mm, aluminium core with plastic tanks, fits 1.3 D Multijet 95, 1.4 MultiAir 136/140/163/170, 1.4 LPG and 1.6 D Multijet 114/120); Nissens 606445 (620 x 396 x 26 mm, aluminium core with plastic tanks, fits 1.6 D Multijet 130 and 2.0 D Multijet 4x4 136/140/150); Valeo 701760; Denso DRM09044 and DRM09045; NRF 59286 and 59290; Ava FT2468 and FT2466; Hella 8MK 366 304-691 and 8MK 366 312-541; Prasco FT060R002 and JE100R001
Core sizes & variants	The 1.4 MultiAir petrols and the smaller diesels (1.3 and 1.6 Multijet up to 120 PS) take the thinner 16 mm core (OE 52009105 / 51965899). The 1.6 Multijet 130 and all 2.0 Multijet 4x4 versions take the thicker 26 mm core (OE 51965905). Both are shared with the Jeep Renegade BU.
Genuine (OE) numbers quoted	52009105; 51965899; 51965905
Fitment notes	Both radiators are supplied with gaskets and seals and have 38.5 mm inlet and outlet connections. Match the engine code first, because the two cores are the same width and height and differ only in depth.

Accuracy note: genuinely worth knowing: radiator hose connection points and mounting brackets on the 500X can differ subtly between facelifted and pre-facelift versions of the same generation, even when the core itself is unchanged.

Confirmed: The Single Most Common Cause of Coolant Leaks Worth Knowing — Fiat 500X Radiator

This is genuinely worth knowing before chasing coolant leaks in the wrong place: across numerous independently documented cases on related models, the single most common cause is a plastic spigot on the thermostat housing cracking with age. A pink or white crusty residue building up around the housing is the first visible warning sign, appearing well before an active drip.

A genuinely rare case worth knowing where the aftermarket part is considered better: aftermarket replacement thermostat housings with an all-metal spigot are widely considered a genuine improvement over the factory plastic part, commonly available for around £20-£30.

It's also genuinely worth knowing a serious safety warning: this engine family is very prone to head gasket failure if run with low coolant, and this can happen before the overheat warning light illuminates. A bubbling sound heard from inside the car, particularly around the glovebox, has been reported as an early sign of a leaking thermostat housing.

Fiat 500X Radiator: The Part That Keeps Everything Else From Cooking

This isn't a part anyone gets excited about, but on the Fiat 500X, overlooked cooling problems are responsible for most serious engine failures that aren't simple wear-and-tear. Catching the early symptoms is about the cheapest insurance available against a major bill later.

Fiat 500X Radiator: Watch: Replacing It

🎬 Watch: 2018 Jeep Renegade 2.4L Radiator Replacement (sister (jeep renegade))

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500X and Renegade share the Small Wide platform and front end; 500X-only hits were fan videos

Before you buy: radiator size and design vary significantly by engine size, transmission type, and whether your car has air conditioning. Always confirm against your VIN before ordering.

Fiat 500X Radiator: What It Does

Keeping the Fiat 500X's engine temperature within safe limits comes down to the radiator's job of transferring heat from the coolant into the surrounding air. Automatic-gearbox versions often build in a second circuit for transmission fluid cooling too, which is exactly why fitting the wrong part number can cause two problems, not one.

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Fiat 500X Radiator: Faults, DIY Difficulty & Aftermarket Advice

These are the same regardless of make or model — see our full Radiator Guide for the three common failure modes, confirming fitment against your VIN, and OEM vs aftermarket guidance.

More Fiat Radiator

The same part, covered across other Fiat models.