toyota2bmw

Mine lasted about 75k miles. Do try to get the OEM water pump. What I thought was a great deal at Amazon turned out to be a DUD! Ended up leaking again just after 3 months. OEM ones should run about $260 or so. But it's not a bad DIY item if you can turn a wrench. Otherwise, you should get someone like member HealthServices to do it for you! I did it with his help and expertise and it was educational and fun.

Wolrab

HealthServices was kind enough to do a very nice DIY on this (I think - could have been thermostat) for the N62 engine. Search around and you'll find it. Even if you don't have the same engine, you'll get an idea of what's involved.

e6t.lab.rat

Had to replace my water pump at about 65k on my 05 545. Like most of my maintenance, I did a DIY and like someone mentioned earlier the life expectancy of these pumps vary greatly. You'll never really know, only until its starts to make some noise.

The pumps very rarely fail immediately. What I mean by that is the impellor won't just disengage and not circulate fluid. Instead you'll start to hear some whinning or some faint chatter/rattle at the water pump. This noise will get progressively louder as the bearings continue to wear. The most common problem to a failed water pump are the bearings at the impellor shaft. When this happens, you'll start to see coolant seeping out behind pulley eventually leading to frequent coolant top off. It was easy to diagnose with a mechanics stethoscope, one you can find very cheap at your local auto store.

Honestly I wouldn't worry about. Use the old adage here, "Don't fix what ain't broke." Do you here dealers or indy shop saying replace waterpumps at xxx miles?

jgt

If I hit 100k on mine I might just replace it. I already have the thermostat and pump on stand by.
Who really knows though. I might want to beat the guy that posted well over 125k on the OEM pump. I'll have AAA on speed dial. lol

Jib535

Mine just went out at 39k. Luckily still under warranty, but it was friggin' scary. Got up to speed on the freeway, then all of a sudden the red alert came on, engine balked hard, reduced power barely let me crawl to the side of the freeway. I had no idea what the hell was going on for a couple seconds. Then I got to spend about 30 minutes on the side of the freeway on the hottest day in L.A. all year.

e6t.lab.rat

^^ I'm guessing you have an electrical water pump? The 545 don't, it's old school belt driven.

tau1

Mine went at around 85K....

BimmerFan52

Who would expect 39K miles?
"If it ain't broke" is a great saying, but at 85K miles I would rather pick the day I have nothing to do, have gathered all the parts and tools and have at it. And picking your day in Scottsdale, AZ where it can range from 50F to 115F can be more than a little important.
I just want 6 cold ones waitin' for me when I'm done, not me waitin' for the tow truck on the side of the road.

ylwjacket

My 2006 just turned 100k. I think I'll do the complete cooling system overhaul.

I just did it on my x5 (2005 3.0). The expansion tank exploded on the freeway. Had it towed, and the tank replaced at dealer. Did all the rest myself. Wasn't too bad. This weekend, I'm doing valve cover gasket, plugs, and oil filter housing gasket on the X.

The E60 will get plugs and coolant system overhaul in about 2 weeks, once I'm done with the X.

moyern83

Your expansion tank exploded? I am on my original pump and thermostat and my 2005 525 is at 96k. I have been thinking about just replacing the water pump and thermostat as PM.

Do most people do this as PM?