Help 2nd broken axle/drivetrain this year
 

I have a 03 x5. 4.4 with 125k miles. It's a love hate relationship. I love it when I'm not sinking money into it. So, about 8 months ago. Pulled away from stop light and big clunk and engine winds up and sounds like metal on metal grinding. No power what so ever and car moves freely even when in park. I'm thinking broken drive train. Took to my bmw mechanic. He said broken axle. Sounded right, well 1400 bucks later I leave and runs fine. Now 8 months later same exact thing happened. So, Now I'm thinking is it the other axle. I can't really which axle is broken since the noise is so loud could be from either side and just doesn't sound like I should be running car in gear. Point being I'm looking up axles on e-bay and such and they are running under 100 dollars. And I would think that I would have some kind of warning that I might be breaking a axle. I have kept the boots up fairly timely. Not perfect but not neglect either. Any words of wisdom? Is it a fairly easy fix I can do on my own. I have changed brakes, water pump, radiator, and such before. 1400 just seems way to high? Or could it have been something else? Thanks.

Sounds like the splines between the front drive shaft and the transfer case are your problem. This is a known problem and there are a couple of different fixes.

I have not seen any reports of the L/R half shaft splines failing.

I let a torn CV boot go too long, so instead of fixing it, I spent $54 for a complete new axle assy. Showed up on the brown truck a few days after ordering it. Cardone brand. Probably Chinese mfr. But so what. It's just a car, not a life support system, and the part has been great for thousands of miles; nice and smooth. It takes maybe an hour to put it in, but I get that not everyone has facility or tools for that, so if you aren't up for it, at least consider some place other than a dealer or even a foreign car indy since there is nothing special about swapping the axle assy. Jack, and some hand tools.

Anyway, I hate reading that someone got slammed in the wallet on something that is readily available and affordable, so I do wish you luck on round 2 of this.

If you're comfy with a water pump or brakes and similar items, then read up and I'd say order from someplace like rockauto (gives you a choice of brands), or just visit a CarQuest or similar, and go for it. You have absolutely nothing to lose by taking off parts and investigating if you can complete it.