Consensus on driveshaft with longer splines?

[kwalk]

After heavy research on this forum and other sources I know what my problem is and after letting it (the car) sit quietly for some months now I'm finally in the mood to get this thing done. I think I'd gotten a little desponded about it. My issue is the transfer case. I want to replace parts chain, output shaft and drive shaft. I found good pricing for both parts, but after researching here there seems to be some back and forth about using a longer drive shaft. Some say using the longer shaft still goes out after some time, some say it's all good. I realize that some that still had the problem may or may not have changed the female part, but what is the final consensus? Can you guys give me some advice? What should I do? To get a longer shaft or to not get a longer shaft? That is the question. Btw, my ride has 73k miles.

Also while I found the parts on the net, does anyone know where I can get them locally here in Houston? Thank you in advance.

[g300d]

I would think that if you are going to open up the transfer case anyway, might as well replace the output spline while you are there?

As I understand the longer shafts are for an alternative repair method to avoid having to replace the transfer case output spline.

Also IIRC, there is no inherent weakness in the mentioned parts, sometimes a combination of factors causes the AC evaporator condensate line output to fall directly on the spline area which causes corrosion and weakens them enough to fail. So the long term fix is to inspect the AC drip line and make sure it is properly positioned.

[Joshdub]

The amount of splines the front driveshaft uses in stock length is a joke. An extra half an inch makes a worlds difference, let alone a whole inch. A new longer days will out last the car.

[David.X5]

If yours spun or otherwise damaged the female part (output spline) on the transfer case, I would replace that in addition to the shaft with the longer spline.

When mine started to get noisy, I found a good used transfer case, put a new chain and seals on it for good luck, and am using that with the drive shaft with the longer splines.

[kwalk]

Thank you guys for your responses. I will change to the longer shaft and will probably go ahead with the output shaft as well. And definitely have them take a look at the ac drip line. I have a some sort of leak there anyway as I have to get the ac charged from time to time.

[jdstrickland]

You HAVE to use the new output shaft else the drive shaft will just spin whats left of the old one. The output shaft will be creamed where the old driveshaft was, is this event the new shaft will only have the splines that have not been damaged already, and the remaining splines will strip out also. You need a new output shaft so the splines are whole.

You can go cheap and use the old output shaft, but then you are faced with the situation that is the basis of your question as to whether the new, longer, driveshaft will work well.

[jdstrickland]

Needing to charge the AC is not relevant to routing of the drain hose. The evaporator coil ices up and then melts, the drain hose is how the water gets out. This hose has absolutely nothing to do with needing to charge the AC.

[kwalk]

Ha, yeah when I mentioned to my husband that the ac needing an occasional charge must have something to do with the drip, he got a good snicker. He also asked me to thank all of you for your responses and input. We will change the chain, go with longer drive shaft, and replace output shaft, pack it with grease and he's going to check the ac drip line to make sure it's in it's proper place. Again thank you all for your responses we really appreciate it. I'm new to BMW's and would be lost if I couldn't come in here and get you guy's knowledge. My husband said that after finding out what and how to, the X5 is easier to do repairs to than the Mazda MPV we used to have. He said that was the hardest vehicle to work on.