Opinions: x35i Front Driveshaft Play

[_ObiJon]

Had the car up in the air to change out the lower control arms. While taking a break, laying down, I shimmed over to the transfer case/drive shaft.

Looking for opinions on the amount of play coming from the output shaft from the TC. I don't think it's excessive but enough to make me o_0. There was 1 very tiny spot of rust on/around the u-joint - maybe visible in the video.

https://youtu.be/O7ka5KWVtaI

2015 x35i. ~81k miles. Purchased at ~75k miles. Unknown if it's ever been changed.

What do you all think? Change it or send it? I was going to change the TC fluid, so if needed, would do it at the same time.

Apologies in advance for quality of video and my leg at the end.

[jbfrancis3]

I saw the video (my prior comment that was here is now redundant). I agree with your skeptical view of the radial slop

[_ObiJon]

Originally Posted by jbfrancis3

Play when you twist the shaft? Unless you're seeing the joint (I don't remember if there's U-joint) slop around, or splines, the play you're feeling is in front diff (ring & pinion) and equally in the TC (chain), both of which are expected to have play that you can readily feel.

Copy. Movement seemed to be more in the input itself (moving perdandiculer to the shaft) as opposed to something in the joint. But thanks for that point. Guibo side had absolutely zero play.

Edit: saw your update. Thank you!

[jbfrancis3]

The shop RRT would be able to better assess whether a concern or not. If you sent James your YT link, he might give you an idea without even taking the car in. They know the X5 platform (all gens) well.

[_ObiJon]

Originally Posted by jbfrancis3

The shop RRT would be able to better assess whether a concern or not. If you sent James your YT link, he might give you an idea without even taking the car in. They know the X5 platform (all gens) well.

Thanks! I'll do that. Never been to RRT but I know they're "right up the road" from me.

[crystalworks]

That movement seems pretty normal to me. Mine was the same. Only way to really tell the U-joints condition for me was to drop the shaft (recently replaced the front shaft). They were very loose compared to the new Febi one. Was glad I replaced it... but who knows, it could have lasted another 100k miles. Either way, was $300 peace of mind that was well worth it.

I have a video for YT on my phone that I haven't posted yet. Been swamped with family stuff (summer) and working on the house.

[tlow98]

Originally Posted by crystalworks

That movement seems pretty normal to me. Mine was the same. Only way to really tell the U-joints condition for me was to drop the shaft (recently replaced the front shaft). They were very loose compared to the new Febi one. Was glad I replaced it... but who knows, it could have lasted another 100k miles. Either way, was $300 peace of mind that was well worth it.

I have a video for YT on my phone that I haven't posted yet. Been swamped with family stuff (summer) and working on the house.

Good to know. Thanks for posting. You think the u joint wears out over time or is water exposure a big factor?

Our car in California barely ever sees water… there’s not. A spec of rust on it.

[tfunk88]

To me that looked more like the normal play in the transfer case/front diff. However, if I’m seeing it incorrectly and that play is simply in the ujoint it definitely needs replaced.

[_ObiJon]

Originally Posted by tfunk88

To me that looked more like the normal play in the transfer case/front diff. However, if I’m seeing it incorrectly and that play is simply in the ujoint it definitely needs replaced.

Thanks! Yes, no movement at all in the u-joint and only in the input itself. Near the end of the video, I did get it to make an audible "clank/clunk" from the up and down movement.

[dentprotony@gmail.com]

Slack in the yoke is from the spline wear on both tcase and the driveshaft, eventually this will create binding and will result in severe stress/wear on the ujoints. After that it will blow up making a hole in the side of your tranny or destroying your iil pan. Both will cost thousands to repair and weeks of downtime, unfortunately. I came up with an upgraded longer spline driveshaft, that comes with serviceable ujoints (skf), balanced, and also has heavy duty yoke/diff flange. These will be available in 1-2 weeks, first 10 units are getting installEd as we speak, will have more available to order very soon!

PS tcase has longer splines than the actual driveshaft yoke, by about 20mm more. My driveshaft uses all the spline area of the transfer case, therefore no additional stress/wobbles on the ujoints, should solve all the front driveshaft issues and be a safe and budget-friendly solution

Originally Posted by _ObiJon

Had the car up in the air to change out the lower control arms. While taking a break, laying down, I shimmed over to the transfer case/drive shaft.

Looking for opinions on the amount of play coming from the output shaft from the TC. I don't think it's excessive but enough to make me o_0. There was 1 very tiny spot of rust on/around the u-joint - maybe visible in the video.

https://youtu.be/O7ka5KWVtaI

2015 x35i. ~81k miles. Purchased at ~75k miles. Unknown if it's ever been changed.

What do you all think? Change it or send it? I was going to change the TC fluid, so if needed, would do it at the same time.

Apologies in advance for quality of video and my leg at the end.

[tlow98]

Originally Posted by dentprotony@gmail.com

Slack in the yoke is from the spline wear on both tcase and the driveshaft, eventually this will create binding and will result in severe stress/wear on the ujoints. After that it will blow up making a hole in the side of your tranny or destroying your iil pan. Both will cost thousands to repair and weeks of downtime, unfortunately. I came up with an upgraded longer spline driveshaft, that comes with serviceable ujoints (skf), balanced, and also has heavy duty yoke/diff flange. These will be available in 1-2 weeks, first 10 units are getting installEd as we speak, will have more available to order very soon!

PS tcase has longer splines than the actual driveshaft yoke, by about 20mm more. My driveshaft uses all the spline area of the transfer case, therefore no additional stress/wobbles on the ujoints, should solve all the front driveshaft issues and be a safe and budget-friendly solution

Love this! Thanks for all your work in this.

[dentprotony@gmail.com]

Originally Posted by tlow98

Love this! Thanks for all your work in this.

Thank you, it was a major challenge to find a reputable driveline shop willing to understand the issue, and willing to make a custom one of a kind yoke mold, measure out and make a pipe that would work with a larger than stock cap ujoints, test fit everything, it definitely wasn’t easy, but we made through all of it !

[crystalworks]

Originally Posted by tlow98

Good to know. Thanks for posting. You think the u joint wears out over time or is water exposure a big factor?

Our car in California barely ever sees water… there’s not. A spec of rust on it.

Tony seems to have laid the typical failure situ out. I did not notice any excessive wear on the driveshaft splines or on the receiving splines in transfer case. But the U-joints were very loose as mentioned. Ours is a Texas car and also rarely sees water. Wish it would see more really.

Regardless... when I installed, I used copper grease on the splines to prevent any corrosion problems in the future. I'll give a heads up when I get that video edited and posted.

[tfunk88]

Originally Posted by dentprotony@gmail.com

Thank you, it was a major challenge to find a reputable driveline shop willing to understand the issue, and willing to make a custom one of a kind yoke mold, measure out and make a pipe that would work with a larger than stock cap ujoints, test fit everything, it definitely wasn’t easy, but we made through all of it !

I just recently replaced my front driveshaft but at some point in the not too distant future I’ll definitely be ordering one of these!

[_ObiJon]

dentprotony@gmail.com I found your pictures on a site/thread (google search) while doing my research. Didn't realize there were yours. Good to know!

tfunk88 I followed your thread. You were experiencing the same issues I am now and your resolution to the problem. Planning on doing a TC fluid change and adaptation reset this weekend. Was hoping the shaft wasn't part of the problem.

[crystalworks]

Here's a screenshot of the corrosion on the splines of our front shaft. It wasn't anything to make note of or worry about. The looseness of the U-joints however, seemed excessive. Plus I wasn't very comfortable with all the surface rust. Got all the files on the computer and will edit that up in the near future.

[_ObiJon]

Originally Posted by crystalworks

Here's a screenshot of the corrosion on the splines of our front shaft. It wasn't anything to make note of or worry about. The looseness of the U-joints however, seemed excessive. Plus I wasn't very comfortable with all the surface rust. Got all the files on the computer and will edit that up in the near future.

Do you believe the u-joint looseness would be more noticeable with it off the vehicle? I dont want to second guess myself, but now I feel as if I'd be more comfortable taking it off and test the joints, to be sure. Especially if it only takes and hour or so to remove.

[tfunk88]

Originally Posted by _ObiJon

Do you believe the u-joint looseness would be more noticeable with it off the vehicle? I dont want to second guess myself, but now I feel as if I'd be more comfortable taking it off and test the joints, to be sure. Especially if it only takes and hour or so to remove.

It won’t take an hour to remove, it’s pretty easy once it’s up on ramps or jack stands. And that’s really the only way to see how “loose” the u joints are. When my original driveshaft was still on couldn’t feel any movement at all. Once I took it off I could feel that the front u joint was very loose (moved quite easily), but no perceptible “play” in the joint itself. There was a TINY bit of play in the rear u joint. The replacement driveshaft the ujoints were much stiffer to move and of course zero play. Didn’t fix my issue, though lol

Fortunately the transfer case fluid change and recalibration did! 👍

[crystalworks]

Originally Posted by _ObiJon

Do you believe the u-joint looseness would be more noticeable with it off the vehicle? I dont want to second guess myself, but now I feel as if I'd be more comfortable taking it off and test the joints, to be sure. Especially if it only takes and hour or so to remove.

As tfunk88 said. 100%. On the car you can't really feel the looseness or sloppiness. Visual inspection seems good only to check for rusting. But the job is 30 minutes to take it down and look. Took me longer because I filmed it and had a 30 minute issue getting the dust boot back on the shaft and transfer case. Other than that... takes longer to get the splash shields down.

[_ObiJon]

Thank you crystalworks, tfunk88 and dentprotony@gmail.com. I'm going to attempt to make time to drop it this weekend and assess the joints. I appreciate the reaponses!

[crystalworks]

Originally Posted by _ObiJon

Thank you crystalworks, tfunk88 and dentprotony@gmail.com. I'm going to attempt to make time to drop it this weekend and assess the joints. I appreciate the reaponses!

BTW, this is a common enough issue that when I went to buy the 4 TTY bolts for the job. DON'T FORGET NEW BOLTS! The dealer parts guy said I was smart to be proactively changing the front shaft. So failures must be common enough that word has made it around the dealership...

[_ObiJon]

Originally Posted by crystalworks

BTW, this is a common enough issue that when I went to buy the 4 TTY bolts for the job. DON'T FORGET NEW BOLTS! The dealer parts guy said I was smart to be proactively changing the front shaft. So failures must be common enough that word has made it around the dealership...

Good call, thank you for this! And it's amazing what you can learn from just a short convo with the parts department.