This package includes most of the items that could cause a leak from the E46 expansion tank. If you're not sure where your leak is coming from you can give the whole area an overhaul using these parts. Most likely it will be from the expansion tank itself but in some cases it could also be from a damaged seal or connector. The automatic transmission models have even more chances of leaks due to the transmission oil cooler also mounted with the expansion tank.
Parts list:
- OEM Behr expansion tank, #17117573781
- OEM Behr expansion tank cap, #17117639022
- Rein upper radiator hose, #17127510952
- OEM coolant level sensor, #17137553919
- Rein transmission thermostat, #17111437362
- Quality aftermarket o-rings for transmission cooler, #17111711987
The only items not included are fresh BMW coolant, heater return hose, lower expansion tank clamp, and the expansion tank mounting plate. The return hose is not a common source for leaks so it's optional (it's also a pain to replace with the manifold still on). The mounting plate holds the tank, transmission thermostat, and the transmission cooler (heat exchanger). There are lots of places for it to leak but the cause is usually a bad o-ring and not the mounting plate itself. We have included the o-rings but you can also order the plate on its own if you prefer. Buying a new mounting plate will make installation easier because you can assemble almost everything off the car where there is more room. The U-shaped “clamp” at the bottom of the expansion tank can be re-used. This rarely fails and any loose tension can be fixed by pinching it together.
If your coolant is more than two years old it should be replaced. You can add it to your order from the options below or pick it up locally and save the shipping cost.
This kit fits cars with automatic transmission only.
All parts are either OE, OEM, or from front-line suppliers. These replacement products meet or exceed all of BMW's original design, fitment, and performance requirements and they carry out testing with ISO and German TUV for quality control. These are the best alternative to more expensive Original BMW parts because they are virtually identical without the inflated price tag. All parts have a two year warranty.
BMW Fitments: 3 SeriesE46 (99-05) > 320i
E46 (99-05) > 323Ci
E46 (99-05) > 323i
E46 (99-05) > 325Ci
E46 (99-05) > 325i
E46 (99-05) > 325xi
E46 (99-05) > 328Ci
E46 (99-05) > 328i
E46 (99-05) > 330Ci
E46 (99-05) > 330i
E46 (99-05) > 330xi
