Engine Coolant Expansion Tank, URO - G87 M2, G80 M3, G82 M4

This part is listed by BMW as BMW part number 17138093924 (17 13 8 093 924) and is described as the URO Parts Coolant Expansion Tank for the engine cooling circuit on the S58 engine in the G87 M2, G80 M3 and G82/G83 M4 (including M4 GT4).

The recommended replacement interval is 100,000 miles on expansion tanks. That's because the plastic is known to get brittle and fragile with age, mileage, and thousands of heat cycles (cold to hot to cold again). Eventually the plastic gets so brittle cracks or holes form, and you'll either get a slow leak or a blow-out that leaves you on the side of the road, overheating. Replace this expansion tank preventatively and you can avoid this type of breakdown. This is a great part to replace while doing a cooling system flush or overhaul.

Cap sold separately. Please see below for BimmerWorld recommended related items.