Rein BMW Cooling System Parts & Accessories for BMW X Series E53 (2000-2006)

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The cooling system is arguably the weakest point in numerous BMWs. If you drive an aging BMW or plan on taking your car to the track like we do, we recommend beefing up your cooling system before going to the track. Generally, the main components in your cooling system that are prone to failure include the following: expansion tank, factory hoses, water pump, thermostat, fan (especially if your vehicle comes factory with a clutch fan), and radiator. Factory BMW expansion tanks are plastic and prone to either breaking off at connection points or combusting. As factory rubber hoses age they either crack or break over time - we offer silicone cooling hose upgrades for most applications to avoid future failures. If you have an older vehicle, your water pump likely comes from the factory with a plastic impeller - we offer upgraded water pumps with metal impellers that are far more reliable. Newer model BMWs utilize electric water pumps - BMW spent millions of dollars engineering these water pumps, but they fail so often that we recommend replacing at 60,000 mile service intervals to avoid being stranded on the side of the road. In terms of thermostats, we offer various upgraded thermostats for racing applications. If your BMW utilizes a clutch fan from the factory, we have several options available in terms of universal electric fans - we recommend replacing these to avoid sending brittle plastic fan blades through your hood. For radiators, we recommend swapping out your radiator for one that does not use plastic connection points like your factory radiator.

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Heater Inlet Pipe
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T#:594330
Part#: 11531705210
In Stock
$ 40.99 USD
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This is the plastic heater inlet pipe that connects the cylinder head to the heater inlet on cars with the M52 or M54 engine.The plastic on this hose becomes brittle over time and eventually leads to failure.
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Rein Coolant Expansion Tank - E46, E53, E83
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T#:402141
Part#: 17117573781
In Stock
$ 76.39 USD
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$ 76.39 USD
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Includes cap and level sensor
OEM Rein Lower Radiator Hose - E53 X5 3.0i 2000-2006
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T#:362444
Part#: 11537508688
Ships in 1 Business Day
$ 35.99 USD
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This lower radiator cooling hose connects the passenger's side bottom of the radiator to the thermostat housing on X5 3.0i with the M54 engine.

This item fits the following BMWs:
2000-2006  E53 BMW  X5 3.0i M54
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Water Pipe
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T#:594365
Part#: 11537502000
In Stock
$ 40.09

This product was last offered at the strikethrough price on
01-10-2026

$ 39.99 USD
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$ 39.99 USD
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Water pipes are essential for proper cooling. If they are cracked, they are going to need to be replaced as soon as possible to avoid overheating your engine. This water pipe runs from the back of the water pump housing to the expansion tank hose. Includes all required seals, needed for the install.
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Rein Lower Radiator Hose - E53 X5 N62 4.4L 4.8L
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T#:362530
Part#: 17127509963
Ships in 3 Business Days
$ 51.38

This product was last offered at the strikethrough price on
04-15-2026

$ 43.99 USD
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$ 43.99 USD
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Replace your cracked or leaking radiator hose to prevent further leaks and potentially catastrophic failure.

Fits the following BMWs:
2003+ E53 BMW X5 N62 4.4L 4.8L

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OEM Rein Expansion Tank Hose - E53 X5 M62 4.4L 4.6L
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T#:363439
Part#: 11537505950
Ships in 1 Business Day
$ 27.99 USD
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Replace your cracked or leaking radiator hose to prevent further leaks and potentially catastrophic failure.

This item fits the following BMWs: 
2000-2003 E53 BMW X5 4.4i 4.6is

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OEM Rein Lower Radiator Hose - E53 X5 M62 4.4L 4.6L
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T#:375370
Part#: 11537500750
Ships in 3 Business Days
$ 33.99 USD
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Replace your cracked or leaking radiator hose to prevent further leaks and potentially catastrophic failure.

This item fits the following BMWs: 
2000-2003 E53 BMW X5 4.4i 4.6is

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OEM Rein Thermostat Coolant Hose - E53 M62
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T#:20210
Part#: 11537500752
Ships in 3 Business Days
$ 21.99 USD
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Over time, coolant hoses begin to get brittle and are susceptible to cracking and splitting. Replace your cracked or leaking coolant hose to prevent further leaks and potentially catastrophic failure.

OEM Rein Upper Radiator Hose - E53 X5 M62 4.4L 4.6L
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T#:379731
Part#: 11537500746
In Stock at Vendor
$ 64.99 USD
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$ 64.99 USD
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Replace your cracked or leaking radiator hose to prevent further leaks and potentially catastrophic failure.

This item fits the following BMWs: 
2000-2003 E53 BMW X5 4.4i 4.6is

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OEM Rein Upper Radiator Hose - E53 X5 N62 4.4L 4.8L
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T#:362526
Part#: 17127526856
Ships in 1 Business Day
$ 83.99 USD
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$ 83.99 USD
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Replace your cracked or leaking radiator hose to prevent further leaks and potentially catastrophic failure.

Fits the following BMWs:
2003+ E53 BMW X5 N62 4.4L 4.8L

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OEM Rein Expansion Tank Hose - E53 X5 N62
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T#:379752
Part#: 17127509965
Ships in 3 Business Days
$ 34.99 USD
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This is one of the hoses exiting from the bottom of the expansion tank on your BMW. Over time, coolant hoses begin to get brittle and are susceptible to cracking and splitting. Replace your cracked or leaking coolant hose to prevent further leaks and potentially catastrophic failure.
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Coolant Expansion Tank
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T#:591949
Part#: 17107514964
Ships in 3 Business Days
$ 80.99 USD
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$ 80.99 USD
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Includes bleeder screw


Thermostat With Housing
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T#:582356
Part#: 11537509227
Ships in 3 Business Days
$ 89.99 USD
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$ 89.99 USD
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Stop leaks before they start with this new Thermostat With Housing from Rein.
Expansion Tank
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T#:592015
Part#: 17137501959
Ships in 2 Business Days
$ 74.99 USD
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$ 74.99 USD
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Includes vent screw and leveling switch
Automatic Transmission Thermostat
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T#:13661147
Part#: 17111437362
Ships on Jun 22, 2026
$ 43.77 USD
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This unit controls the temperature of your automatic transmission fluid

Rein Expansion Tank Hose - E53
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T#:375755
Part#: 11537500735
Back Ordered
$ 22.99 USD
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Hose running from the expansion tank. Made in Germany.

OEM Rein Upper Radiator Hose - E53 X5 3.0i 2000-2006
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T#:6979
Part#: 11537500733
Special Order: No Guaranteed ETA
$ 39.69

This product was last offered at the strikethrough price on
05-15-2026

$ 37.99 USD
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$ 37.99 USD
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This upper radiator cooling hose connects the drivers side top of the radiator to the thermostat housing on X5 3.0i with the M54 engine.

This item fits the following BMWs:
2000-2006 E53 BMW X5 3.0i M54
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Rein Coolant Bleeder Screw CHW1575 - Priced Each
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T#:591955
Part#: 17111712788
In Stock
$ 4.99 USD
Free Shipping on orders $49 and up
Coolant Bleeder Screw is a critical component for maintaining your BMW’s cooling system. Designed to release trapped air from the coolant lines, this screw ensures efficient coolant flow and prevents overheating. Specifically engineered for BMW models, it enhances the overall performance and longevity of your engine by maintaining proper temperature regulation. Comes with O-Ring.
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Rein Cooling O-Ring - E53, E60, E63, E64, E65, E66, E70
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T#:362446
Part#: 11531710048
In Stock
$ 4.07 USD
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Seals the rear of the water transfer pipe to the block
OEM Rein Expansion Tank Cap - BMW E32 E34 E36 E38 E39 E46 & More ...
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T#:340541
Part#: 17111742231
In Stock
$ 17.99 USD
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This radiator expansion tank cap is used most BMW's from 1991-2006. It is a common failure item. When this item fails, it cannot hold pressure which results in your BMW overheating. If you are overhauling your coolant system, now is the time to consider preventative replacing this cap. It is also referred to as the coolant reservoir cap.
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Expansion Tank Mounting Plate
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T#:591946
Part#: 17101439110
Ships in 3 Business Days
$ 80.99 USD
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$ 80.99 USD
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BMW Radiator Hose Kit - 11537500750
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Rein - Corporate Logo
T#:46753499
Part#: CHK0030R
Ships in 3 Business Days
$ 50.99 USD
Free Shipping on orders $49 and up
Keep your cooling system sealed, strong, and ready for anything with this Rein radiator hose kit—your all-in-one fix for cracked, leaking, or worn factory hoses. Years of heat, pressure, and age can cause rubber to weaken, split, or swell, setting the stage for coolant leaks and potential overheating. Rein hoses are engineered to meet or exceed OEM standards, built from premium, heat-resistant materials that can take on extreme temperatures and system pressures without faltering. Each hose features factory-correct bends, fittings, and diameters for an exact, hassle-free installation—no cutting or forcing required. Whether you’re tackling a full cooling system refresh or chasing down a small coolant leak, this Rein kit provides everything needed to restore confidence and performance under the hood. Why choose this Rein radiator hose kit: Factory-level precision – Direct-fit replacements that deliver OEM-quality reliability. Built to last – Resists cracking, swelling, and chemical damage from daily heat cycling. Confidence restored – Prevents coolant loss, overheating, and on-road breakdowns. All-in-one upgrade – Includes upper and lower hoses for a complete system refresh. If keeping your BMW’s cooling system running tight and trouble-free is the goal, Rein brings the dependable quality and fitment you can count on—engineered to perform just like factory, mile after mile.
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OEM Rein Cylinder Head To Expansion Tank Coolant Hose - E53 X5 N62 4....
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T#:379756
Part#: 17127509967
Ships in 3 Business Days
$ 38.99 USD
Free Shipping on orders $49 and up

Replace your cracked or leaking radiator hose to prevent further leaks and potentially catastrophic failure.

Fits the following BMWs:
2003+ E53 BMW X5 N62 4.4L 4.8L

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BMW Expansion Tank With Cap - 17107514964
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T#:46616026
Part#: EPK0025
Ships in 3 Business Days
$ 74.99 USD
Free Shipping on orders $49 and up
The coolant expansion tank provides a place for excess coolant to flow as temperatures rise and fall. Because it’s exposed to constant heat cycles and pressure changes, it can eventually crack, split, or suffer damage to its nipples or mounting points. Keeping coolant properly contained within the system is essential, so if your tank shows signs of wear or damage, replacement is necessary. This direct-fit replacement installs easily and delivers the same heating and cooling performance as the factory unit. When replacing the tank, be sure to have additional coolant on hand. ECS Tuning carries a full range of vehicle-specific coolants designed to meet OEM specifications. Most German vehicles require specialized formulas—using the correct coolant will help prevent corrosion and ensure long-term reliability.
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Rein - Thermostat Assembly 82C - X5 M62, X5 N62
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T#:34080721
Part#: 17107559966
Ships in 3 Business Days
$ 51.99

This product was last offered at the strikethrough price on
04-28-2026

$ 48.99 USD
Free Shipping on orders $49 and up
$ 48.99 USD
Free Shipping on orders $49 and up

Thermostat Assembly 82C is a high-quality, precision-engineered component designed to regulate the engine's cooling system effectively. Manufactured to meet or exceed OEM specifications, this thermostat helps ensure optimal engine performance by maintaining the ideal operating temperature. Available from Turner Motorsport, this part offers superior durability and reliability for a wide range of vehicle models.

  • Designed for precise temperature control
  • Maintains engine at the optimal 82°C (180°F) temperature
  • Helps prevent overheating and improves fuel efficiency
  • Direct fit replacement for hassle-free installation
  • Manufactured from high-quality materials for long-lasting performance

Upgrade your vehicle's cooling system with this essential Thermostat Assembly 82C, ensuring smooth engine operation under various driving conditions.

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OEM Rein Coolant Hose - E53 X5
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T#:379748
Part#: 64218409064
Ships in 3 Business Days
$ 12.99 USD
Free Shipping on orders $49 and up
Over time, coolant hoses begin to get brittle and are susceptible to cracking and splitting. Replace your cracked or leaking coolant hose to prevent further leaks and potentially catastrophic failure.
Expansion Tank Hose
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T#:375341
Part#: 11531439123
Ships in 3 Business Days
$ 32.99 USD
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OEM Rein Expansion Tank Hose - E53 X5 N62 4.4L 4.8L
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T#:379797
Part#: 17127509966
Ships in 3 Business Days
$ 32.99 USD
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Replace your cracked or leaking radiator hose to prevent further leaks and potentially catastrophic failure.

Fits the following BMWs:
2003+ E53 BMW X5 N62 4.4L 4.8L

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OEM Rein Heater Coolant Hose - E53
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T#:12845
Part#: 64218409063
Ships in 3 Business Days
$ 10.99 USD
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Over time, coolant hoses begin to get brittle and are susceptible to cracking and splitting. Replace your cracked or leaking coolant hose to prevent further leaks and potentially catastrophic failure.
Expansion Tank With Cap
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T#:46616025
Part#: EPK0138
Ships in 3 Business Days
$ 71.99 USD
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The coolant expansion tank allows excess coolant to flow in and out as temperatures rise and fall. Over time, repeated exposure to extreme temperature changes can cause the tank to crack, split, or break. To keep your cooling system sealed and functioning properly, any tank showing signs of damage—such as cracks, broken nipples, or compromised mounting points—should be replaced.
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BMW Radiator Hose Kit - 17127509963
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Rein - Corporate Logo
T#:46719193
Part#: CHK0032P
Ships in 3 Business Days
$ 76.99 USD
Free Shipping on orders $49 and up
Keep your cooling system sealed, strong, and ready for anything with this Rein radiator hose kit—your all-in-one fix for cracked, leaking, or worn factory hoses. Years of heat, pressure, and age can cause rubber to weaken, split, or swell, setting the stage for coolant leaks and potential overheating. Rein hoses are engineered to meet or exceed OEM standards, built from premium, heat-resistant materials that can take on extreme temperatures and system pressures without faltering. Each hose features factory-correct bends, fittings, and diameters for an exact, hassle-free installation—no cutting or forcing required. Whether you’re tackling a full cooling system refresh or chasing down a small coolant leak, this Rein kit provides everything needed to restore confidence and performance under the hood. Why choose this Rein radiator hose kit: Factory-level precision – Direct-fit replacements that deliver OEM-quality reliability. Built to last – Resists cracking, swelling, and chemical damage from daily heat cycling. Confidence restored – Prevents coolant loss, overheating, and on-road breakdowns. All-in-one upgrade – Includes upper and lower hoses for a complete system refresh. If keeping your BMW’s cooling system running tight and trouble-free is the goal, Rein brings the dependable quality and fitment you can count on—engineered to perform just like factory, mile after mile.
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Rein Coolant Return Pipe - N62 N73
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T#:386411
Part#: 11511439976
Special Order: No Guaranteed ETA
$ 14.99 USD
Free Shipping on orders $49 and up
This is the coolant return pipe on the back of the water pump on the N62 and N73 engines used in the E53 X5, E60 545/550, E63 645/650, E65 745/750, E70 X5, and F02 750. This pipe connects the water pump to the valley pan and it's a compression fitting (no o-rings). Whenever the water pump or valley pan are replaced this tube should also be replaced. This is one area where you don't want to go back and re-do your work because of a leaking fitting! In German, Rein means Pure. In the automotive industry the Rein name has quickly come to represent quality. With fitments for some of the worldaEURtms finest automobiles including BMW and Mini and guaranteed OE quality, Rein is a name you can trust.
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Radiator Support Bracket
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T#:14122755
Part#: 17117514402
Special Order: No Guaranteed ETA
$ 8.99 USD
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Mounts to top of radiator bracket, 2 per vehicle.