Oil Separation & Breather System for BMW Z Series E85/6 (2003-2008)

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Every car has a crankcase vent system that is supposed to suppress oil from making it into the intake ports and combustion chamber. A good functioning system will separate oil from the atmosphere and return it to the oil pan (or collect it in a catch can) while allowing the leftover vapors to burn in the combustion chamber or recirculate through the system. This has always been known as a PCV system (Positive Crankcase Ventilation) but BMW has several other names for it - oil separator, crankcase vent (CCV), and cyclonic separator. Failures in the system will allow raw oil to enter the intake and eventually into the engine itself which can have disastrous effects on engine performance and longevity. As emissions regulations on oil and gas venting have gotten more stringent the PCV systems have gotten more complex and failure prone. And because the CCV is intertwined with other systems you could experience rough running, loss of power, higher oil consumption, misfiring, stalling, or other annoying issues. There is no replacement interval for these so we recommend inspecting your crankcase vent system as part of your regular maintenance routines. Symptoms of a bad crankcase vent are: whitish or yellowish film on the underside of the oil cap, whistling/squealing noises (not caused by a belt), suction on the oil cap that makes it hard to unscrew, large amounts of white smoke from the exhaust, and excessive oil consumption.

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Turner Motorsport - Corporate Logo
T#:46203577
Part#: 058973LA02
In Stock
$ 101.99

This product was last offered at the strikethrough price on
06-24-2026

$ 78.99 USD
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$ 78.99 USD
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Due to weak plastic construction, the factory plastic crankcase ventilation breather hose is known to fail. After years of exposure to piping-hot engine bay temperatures and chemical-laden oil vapors, the corrugated plastic tubing can crack, crumble, or fail altogether.

We set out to bulletproof your N52 CCV system with a durable silicone breather hose, designed to provide a comprehensive upgrade and permanent replacement for the factory plastic hose. By replacing the flimsy, heat-hardened OEM plastic hose with a four-ply fluorosilicone hose, you'll experience peace of mind knowing your N52 is free from the inevitable return of oil leaks, vacuum leaks, and drivability concerns that would have been.

This breather hose is found at the front of the engine, and is used to connect the oil separator to the valve cover. It replaces OEM part number 11157522931.

Features:

Silicone construction ensures a durable replacement that is sure to outlast OE plastic
Designed as a direct replacement for the factory breather hose
Retains heating function and OE electrical connector
Design:

Four-ply wire-reinforced fluorosilicone hose is designed to resist degradation due to exposure to oil vapors
O-rings are pre-installed in OE connectors for a lasting seal
Includes pre-installed zinc-coated hose clamps for durability and corrosion resistance
Product Development:

Our Silicone CCV Hose Upgrade was designed, engineered, tested, and quality inspected by our Research and Development team in our Wadsworth, Ohio, facility. We strive for the highest level of precision and quality through leading-edge product development technology, including FARO laser scanning for reverse engineering and quality inspection, SolidWorks 3D CAD modelling, rapid prototyping utilizing our in-house 3D printer, and rigorous long-term product testing.

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Turner Motorsport - Corporate Logo
T#:2895
Part#: 11617533400-E85
Ships in 1 day
Sale - Save 5% $ 406.99

This product was last offered at the strikethrough price on
05-03-2026

$ 386.64 USD
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Sale - Save 5%
$ 406.99

This product was last offered at the strikethrough price on
05-03-2026

$ 386.64 USD
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This Crankcase Vent / Oil Separator Repair Kit includes the updated oil separator valve, oil dipstick guide tube and hoses. This kit fits E85 Z4 2.5i Z4 3.0i 2003-2005.

This item fits the following BMWs:
2003-2006 E85 BMW Z4 2.5i Z4 3.0i
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Turner Motorsport - Corporate Logo
T#:46203579
Part#: 058981LA02
In Stock
$ 101.99

This product was last offered at the strikethrough price on
06-14-2026

$ 59.99 USD
Free Shipping
$ 59.99 USD
Free Shipping

Due to weak plastic construction, the factory plastic crankcase ventilation breather hose is known to fail. After years of exposure to piping-hot engine bay temperatures and chemical-laden oil vapors, the corrugated plastic tubing can crack, crumble, or fail altogether.

Upgrade your N52 CCV system with this durable silicone oil separator hose, designed to provide a comprehensive upgrade and permanent replacement for the factory plastic hose. By replacing the flimsy, heat-hardened OEM plastic hose with a four-ply fluorosilicone hose from Turner Motorsport, you'll experience peace of mind knowing your N52 is free from the inevitable return of oil leaks, vacuum leaks, and drivability concerns that would have been.

This hose is located underneath the intake manifold and is used to connect the oil separator to the induction tract. It replaces OEM part number 11617559530.

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Bremmen Parts - Corporate Logo
T#:640155
Part#: 11157559528
In Stock
Sale - Save 20% $ 48.99

This product was last offered at the strikethrough price on
05-03-2026

$ 39.16 USD
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Sale - Save 20%
$ 48.99

This product was last offered at the strikethrough price on
05-03-2026

$ 39.16 USD
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This valve cover vent hose helps to vent the crankcase fumes on BMW's with the N51 / N52 6 cylinder engines. If replacing the valve cover, we recommend purchasing this item as well as it often will break while removing it from the valve cover.
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Bremmen Parts - Corporate Logo
T#:641646
Part#: 11617501566S1
In Stock
Sale - Save 15% $ 95.99

This product was last offered at the strikethrough price on
05-03-2026

$ 81.59 USD
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Sale - Save 15%
$ 95.99

This product was last offered at the strikethrough price on
05-03-2026

$ 81.59 USD
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BMW has an ongoing issue with oil separators freezing in cold weather if driving is done before the vehicle is fully warmed up. There is often a howling noise followed by numerous oil leaks. The crankcase breather valve is used to purge the oil vapor from the engine block into the valve cover. However, sometimes condensation can cause it to freeze, causing the entire oil separator system to fail, crack, and disintegrate. Replace all the components of the oil separator system together to prevent damage to all the aspects of your engine. Level 1 kit includes the following; Oil separator Hose from oil separator to dipstick tube Hose from oil separator to valve cover Hose from intake manifold back to the connector hose Hose from oil separator up to the intake manifold
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Bremmen Parts - Corporate Logo
T#:33746535
Part#: 11617559530
In Stock
Sale - Save 20% $ 42.99

This product was last offered at the strikethrough price on
05-03-2026

$ 34.26 USD
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Sale - Save 20%
$ 42.99

This product was last offered at the strikethrough price on
05-03-2026

$ 34.26 USD
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Bremmen Parts - Corporate Logo
T#:8677203
Part#: 11617531423
Ships in 6 Business Days
Sale - Save 4% $ 69.99

This product was last offered at the strikethrough price on
05-03-2026

$ 67.20 USD
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Sale - Save 4%
$ 69.99

This product was last offered at the strikethrough price on
05-03-2026

$ 67.20 USD
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Bremmen Parts - Corporate Logo
T#:30629688
Part#: 11157537701
In Stock
Sale - Save 21% $ 28.99

This product was last offered at the strikethrough price on
05-03-2026

$ 22.84 USD
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Sale - Save 21%
$ 28.99

This product was last offered at the strikethrough price on
05-03-2026

$ 22.84 USD
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Bremmen Parts - Corporate Logo
T#:640147
Part#: 11611432559
In Stock
Sale - Save 22% $ 23.99

This product was last offered at the strikethrough price on
05-03-2026

$ 18.76 USD
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Sale - Save 22%
$ 23.99

This product was last offered at the strikethrough price on
05-03-2026

$ 18.76 USD
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Crankcase Vent Hose - From Valve Cover to Oil Separator - Fit BMWs with the M52 or M54 6 cylinder engine

Bremmen Parts - Corporate Logo
T#:558205
Part#: 11617533329
In Stock
Sale - Save 30% $ 6.99

This product was last offered at the strikethrough price on
05-03-2026

$ 4.89 USD
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Seals the PCV angle connector to the intake manifold
Bremmen Parts - Corporate Logo
T#:30629689
Part#: 11157532649
In Stock
Sale - Save 24% $ 15.99

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$ 12.23 USD
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Sale - Save 24%
$ 15.99

This product was last offered at the strikethrough price on
05-03-2026

$ 12.23 USD
Free Shipping on orders $49 and up