URO Parts17137787039 Expansion Tank, Includes Clamp

Does it Fit just as OEM. I have replaced the old ones always with this brand Uro//parts. and for peace on mind add gasket maker seal black or grey. yeah. that's for oil seal. but work just perfect in cooling system. you will never have coolant leaks.

This part was bought to replace a BMW factory tank that was leaking through a split on the side. It fixed the leak, but the low coolant light stayed on, despite repeated attempts at bleeding and filling, hot and cold, letting it settle a few days, and trying again. The short story is, a different brand fixed it immediately.The replacement part was shipped loose in a box with no country of origin shown. It feels very sturdy, and there was only 1.5 ounces difference between this and the factory part, though I don't know if that is due to construction or perhaps 1.5 ounces of saturation in the old part. As many people have experienced, the low coolant light stayed on. Because the light was sometimes off, it seemed like it might have been a legitimate indication. We tried bleeding and filling, sometimes hot, sometimes cold, and the light would come and go, but never stay off. We checked the sensor and swapped it with the one in the windshield washer tank with no success. After trying everything we could think of, we bought a different brand, which installed and worked without any difficulty.After reading so many stories about problems with the low coolant light, even for factory parts, I figured there must be something more complicated about this tank than meets the eye, so I cut the old one open to find out (see pictures). Yes, it is more complicated than a simple tank. There are multiple compartments inside, and two floats, one for the visual red stick indicator, and one for the low coolant light. Those that say the magnet comes loose and rattles in the tank are probably mistaken - it is likely they are hearing the second float, which is inaccessible unless the tank is cut open. Most surprising to me is that the light sensor seemed to work on a bench test. With a continuity meter, the switch was open with the tank empty and standing upright, and would close when flipping the tank over, simulating the float going up. I don't know why it would work on the bench, but not the car, but I suspect that there was a flaw on the injection molding for the plastic that prevented one of the internal compartments from filling properly, even if one of the compartments was full. Or maybe temperature changes would cause the float and plastic to slightly change causing the float to stick. I don't know, only that we tried really hard for a month before getting another part.

Fast over-night shipment, which was great. Installed fine too. Refilled coolant and bled system.No leaks. BUT....LIKE SEVERAL OTHER REVIEWS have reported, the coolant level sensor warning illuminated on the instrument cluster shortly after starting engine. And stays on. And the coolant level was actually fine. I purchased a replacement coolant level sensor installed it and same problem. Sensor reports low coolant. I removed the reservoir from my vehicle and found that apparently the magnet that ought to be attached to the float instead became detached. It was rattling around inside the reservoir. When the magnet then falls to the bottom of the reservoir, it activates the low-coolant sensor (which is just a reed switch). It's either a design or manufacturing defect. Lots of unnecessary time for me dealing with this...and buying an unnecessary coolant sensor too. Be advised.

When I purchased my car the previous owner had replaced this part. It was some no name part and within no time at all, I started to notice a leak on the pavement of coolant. I knew from the residue that it was coming from this part somewhere but I could never locate the exact spot. It did eventually get worse and I thought it may have been more than just the expansion tank. Nope. I replaced that and my leak was gone. It's also a very good idea, if you already haven't done so, to replace the entire cooling system parts (thermostat, upper/lower radiator hoses, etc). The e46 series have known problems with cooling and if you are replacing the expansion tank, you might as well get it all in one shot.

- 2001 BMW 330CI Automatic -Good quality for the price. Seems as good as OE, but time will tell. Comes with the bottom snap/clip connector, but no coolant level sensor.BE AWARE: For automatic transmissions, the transmission thermostat will likely snap off at the top from the force it takes to break the O-ring seal when you separate the tank from the bracket. The thermostat is a pressure fit and sits in the largest opening on the bracket which the large opening on the bottom of the expansion tank slips down onto. I've had to remove the tank twice and both times the top of the thermostat broke.The last time it had been replaced 5 years earlier. Order the transmission thermostat  Beck Arnley 143-0872 Thermostat  as a just-in-case scenario. It can always be returned if yours doesn't break.

This part fit nicely and wasn't a beat down to fit like others in the past. Don't know that this part should ever get 5 stars by any manufacturer as it seems like a weak point in the cooling system (I am on my 4th one in 9 years). They always crack vertically on one of the corners so it would be wise to have an extra one on hand especially if yours is a couple of years old.

It's been about 60 days since I replaced this part on my bimmer and I have no complains. It works fine.. no ruptures, no cracks or leaks. The price of this item in amazon compared to OEM dealership's price is a big difference. However, I cannot disagree that the structure/integrity of the tank vs the OEM's would be the same, but there is always a slight difference. I guess I'll be able to have a better opinion about this product in two years from now (see how long it last). In the mean while, I am satisfied with it. it works as it supposed to.For those who are not familiar with BMW's, the replacement of this part can be complicated and frustrating. I would definitely recommend to find someone familiar with bimmers to take care of your cooling system problem or you can pay the full price dealer's repair service. $$$$ .

Easy to install everything fit perfect , holding right now . Now to see how long it’ll last

I purchased this item and the coolant light stays on. I have changed the sensor and diagnosed this product will cause the low coolant light to come on even if it is full.