HELP: Coolant Leak!
 

2001 X5 4.4 with 158k on the clock.

Wife called earlier this week and said coolant light came on, but temp gauge was fine. Checked it when I got home, and expansion tank was almost empty. Refilled it, but still getting a leak from somewhere at the front, passenger side, of the engine. After shutting engine off, I have a puddle about the size of a dinner plate the next morning.

Also, there is a slight clunking noise coming from the front of the engine also. Can't see any obvious signs of where the leak is coming from. With engine running and expansion tank cap off, coolant is circulating with some pressure. At a loss here, any help would be appreciated.

Thanks,

i had a leak in my expansion tank also from a crack, and it would only leak when it got warm or hot from expanding. the only way to find it is to just turn the car on, maybe take a short drive, and then just look where its leaking from.

i also had a leaking expansion tank, leak from top/bottom joint in one corner. When it removed it to replace, i found out its been leaking at the level switch. Easy job to replace, also found the part from ECS complete with level switch for $79.99 should that be the part you need to replace.

i also had a leaking expansion tank, leak from top/bottom joint in one corner. When it removed it to replace, i found out its also been leaking at the level switch bottom of tank. Easy job to replace, also found the part from ECS complete with level switch for $79.99 should that be the part you need to replace.

UPDATE: It was the water pump. Wish it had been the valley pan, would have been about $200 cheaper. Reason the water pump repair was more, is because I also had two tensioners that failed when re-tensioning the S-belt.

Valley pan is leaking a little bit too, but I'm going to take that one on myself down the road, probably when I do the valve gaskets.

boyce89976, curious why you got rid of a 2010 X5d in favor of 2001 X5. Didn't like the diesel performance?

Actually, have had the 2001 for 11 years now. The X5d left us b/c she spent most of her time at the BMW dealership... almost 40 days since Oct. to be exact. In the end, they got her fixed, but I just couldn't stomach how much the repair process would have been had it not been covered by warranty... oh, and there was the small issue of BMW not providing me with detailed work orders and fault codes for the repairs "unless I subpoena'd them".
:stickpoke

My 4.4i has 156k, and just last year I had to replace not only the cooler pump (which I had my mechanic do), but I had to replace the radiator as coolant was literally coming out of the manufactured seams.