Driveline Refresh

[epdarks]

I had a shop look at it a few weeks ago. They recommended new front and rear driveshafts.

Will check for visible issues first as someone mentioned. If I can solve the problem by replacing a few smaller parts then why not.

[Skyline]

Originally Posted by epdarks

I had a shop look at it a few weeks ago. They recommended new front and rear driveshafts.

Will check for visible issues first as someone mentioned. If I can solve the problem by replacing a few smaller parts then why not.

Well, that doesn't sound good. But there are a bunch of serviceable components in both driveshafts. Did the shop say what part of each driveshaft was bad? I would think the only bad components that could condemn the driveshafts would be the splines in the front shaft, (perhaps also requiring attention inside the TC), and the u-joint in the rear shaft.

Although if my rear driveshaft had a bad u-joint, I'd take the whole shaft to my local driveshaft shop. Even is there was no way to service the u-joint, perhaps they could cut the joint out, and weld in a serviceable u-joint;(then rebalance). Probably would be a small fraction of the cost of a new driveshaft.

I just don't get how a cars driveshaft should fail at ALL without either serious off-roading,(done that), or high HP drag strip use.

[fmugur]

This is the part that failed, caused the clunking noise and had a good play on my rear drive shaft. It looks like the rear driveshaft connects directly in the rear differential but it has this constant velocity joint in between (part 17).

[epdarks]

So I got it on blocks and had a good look around.

The front shaft is super tight. No slop when shifting into D or R, and not able to twist it manually with the truck off.

The rear shaft guibo and center support bearing are completely shot. I'm sure the constant velocity joint is bad too. So the entire rear drive shaft is coming out tomorrow, front as well to inspect splines.

Did the engine mount test, no abnormal lifting or twisting of the engine. So those must have been done at some point.

More news tomorrow after my PB blaster goes to work tonight.

Thanks for all of the help.

[epdarks]

Got the front shaft out today. The guibo looks a lot worse now that I have a good look at it. By the way, the splines appear to be completely stripped. I have no idea how they held on. The grease on the front driveshaft splines was still bright blue... Factory?

I've decided to start by replacing the front shaft, guibo and bolts. Hopefully this isolates my clunking issue.

On second look, the rear driveshaft slop that I was seeing is actually the rear axels/CV. The shaft itself still has a bright white sticker on it which makes me believe it simply cannot be original. I'm not sure how much slop is supposed to be present in the constant velocity joint.

Considering the rear shaft is a bear of a job compared to the front, plan is to start with the front and bolt it all back together. If there is still slop then we will go from there. Hope to order parts tomorrow and put it back together early next week.

[Skyline]

Originally Posted by epdarks

Got the front shaft out today. The guibo looks a lot worse now that I have a good look at it. By the way, the splines appear to be completely stripped. I have no idea how they held on. The grease on the front driveshaft splines was still bright blue... Factory?

I've decided to start by replacing the front shaft, guibo and bolts. Hopefully this isolates my clunking issue.

On second look, the rear driveshaft slop that I was seeing is actually the rear axels/CV. The shaft itself still has a bright white sticker on it which makes me believe it simply cannot be original. I'm not sure how much slop is supposed to be present in the constant velocity joint.

Considering the rear shaft is a bear of a job compared to the front, plan is to start with the front and bolt it all back together. If there is still slop then we will go from there. Hope to order parts tomorrow and put it back together early next week.

So what's the condition of the internal splines of the output shaft in the TC that the driveshaft goes into? Hard to believe they are good if the splines of the driveshaft are completely stripped. If the inside is stripped, you can either get a driveshaft that has a bit longer splines, (thereby engaging the undamaged part of the internal splines in the output shaft), or replace the output shaft in the TC, or BOTH. But a stock shaft if the output shaft of the TC is already damaged will not last long.

Here's where you can get those parts:

BMW X5 Transfer Case Parts : Automatic, Standard Transmission and Transfer Case Rebuild Kits, Cobra Transmission Parts 1-800-293-1848

If you DO decide to replace the output shaft, I would certainly do all the bearings and seals in the transfer case, as it's got to come apart anyway. You can get a good look at the chain at that time, ($90 to replace). This site also has a video on dissasembly, it's really not that hard.

[epdarks]

Originally Posted by Skyline

So what's the condition of the internal splines of the output shaft in the TC that the driveshaft goes into? Hard to believe they are good if the splines of the driveshaft are completely stripped. If the inside is stripped, you can either get a driveshaft that has a bit longer splines, (thereby engaging the undamaged part of the internal splines in the output shaft), or replace the output shaft in the TC, or BOTH. But a stock shaft if the output shaft of the TC is already damaged will not last long.

Here's where you can get those parts:

BMW X5 Transfer Case Parts : Automatic, Standard Transmission and Transfer Case Rebuild Kits, Cobra Transmission Parts 1-800-293-1848

If you DO decide to replace the output shaft, I would certainly do all the bearings and seals in the transfer case, as it's got to come apart anyway. You can get a good look at the chain at that time, ($90 to replace). This site also has a video on dissasembly, it's really not that hard.

To be perfectly fair, I didn't look at the internal splines of the TC. From my research, I thought the shafts could strip and the TC splines be perfectly fine?

I will look at that tonight. I wanted to just buy a new front shaft and put that in, but it sounds like I run a risk stripping that one too.

I have this epic road trip planned for the X in mid-December... I'm starting to sweat now.

Thanks, Skyline.

[epdarks]

Ok, here are some pics.

Shaft...



TC...


So to me the front shaft looks striped when you compare it with this...



And pics of the TC for reference...



My driveshaft spines are not flat at the top, they are sharp and have some exposed metal (shiny part). The TC splines I am just not sure of... What are they supposed to look like?

I spoke with the PO via text. He said both shafts are original. He did remove them when he did the trans 2 years ago, but deemed them fine to use. He isn't the type to half ass it, either.

So my verdict is:
Replace front shaft, guibo, supporting parts

Unsure:
TC input striped?
TC chain

Ay help???? Thanks guys..... Couldn't do this project without help from the forum.

[JCL]

The root and the top of each spline should be more square cut, less sharp. They don't look stripped in your shots, that means the tooth is worn off completely. They do look very worn. A little hard to tell without comparing the length of the splines.

Replace both, IMO.

Check the chain before you take the case apart, to see how loose it is and whether it needs replacing at the same time.

[Roadkill]

Man, that is really a poor design. Guess I should be glad I have xDrive.