2025 BMW 430i Oil Filter Housing Coolant Leak TSB

Owners of certain 2025 BMW vehicles, including the 330i, 430i, X3, X4, and 530i, may notice coolant leaking from the oil filter housing. This issue is addressed by BMW Technical Service Bulletin (TSB) SIB 11 10 25, which outlines the cause and the necessary repair procedure. The problem specifically affects vehicles equipped with B46D, B48P, or XB1G (PHEV) four-cylinder engines.

Symptoms

The primary symptom of this issue is visible coolant leaking from the oil filter housing. This external leak indicates a compromise in the cooling system, which could lead to low coolant levels if not addressed.

Cause

BMW has identified that the seal for the oil filter housing can exert excessive pressure on the bushing or insert within the housing. This pressure can deform the bushing or insert, leading to a crack and subsequently an external coolant leak. An image in the TSB illustrates a crack in the coolant bushing/insert in the oil filter housing.

Repair Procedure Summary

To correct the BMW oil filter housing leak, technicians must follow specific repair instructions. The procedure involves removing the full-flow oil filter completely, as outlined in Repair Instruction 11 42 020. Once the oil filter is removed, the sealing kit and bushing for the full-flow oil filter are replaced using Repair Instruction 11 42 601. This ensures that the deformed components are exchanged for new, redesigned parts to prevent future leaks.

For some models, Repair Instruction 11 42 601 might not be immediately visible. In such cases, technicians are advised to reference a G45 B48P model in ISTA/AIR to access the correct repair instructions.

Required Parts and Fluids

The repair for the BMW oil filter housing leak requires specific parts and fluids. Technicians must determine the exact part numbers by entering the vehicle's VIN or chassis number into BMW's ETK or AIR systems to ensure compatibility with specific equipment and options. Key components and materials include:

• Bush: Part Number 11 42 8 490 951 (Quantity: 1)
• Gasket set: Part Number 11 42 9 886 567 (Quantity: 1)
• Oil-filter element: Refer to ETK/AIR for the correct replacement part.
• HT-12 Antifreeze RTU (Bulk Drum DN = 1/10 Liter) (Pre-mix): Part Number 83 19 5 A32 851 (As needed)
• Antifreeze/Coolant (DN = 1 Gallon Concentrate) - HT-12: Part Number 83 19 2 468 442 (As needed)
• BMW approved engine oil: Part Number SI B 11 01 21 (As needed)

Additional small parts, fluids, lubricants, and one-time use fasteners not specified above must be selected from the Electronic Parts Catalog or other approved BMW Group resources according to the vehicle type.

Warranty Coverage

Repairs performed under TSB SIB 11 10 25, with Repair Code 1142004800, are covered under the terms of the BMW New Vehicle Limited Warranty for Passenger Cars and Light Trucks. They may also be covered under the BMW Certified Pre-Owned Program, depending on the vehicle's eligibility.

Important Notes for Owners

If you experience coolant leaking from your oil filter housing, it is important to have your vehicle inspected by an authorized BMW service center. The repair involves specialized procedures and parts to ensure the issue is correctly resolved. The labor operations associated with this repair include draining and topping up coolant (17 00 008 or 17 00 508), verifying the leak (17 99 000*), diagnosis (00 58 500*), and the removal/installation of the oil filter (11 42 520) and replacement of the sealing kit and bushing (11 42 601).

NHTSA ID: 11026946