Clunk in the Trunk

[FunfDreisig]

Originally Posted by MAK3N3

Mount a go pro under there or in your cargo area to play back the sounds over and over to isolate the sound or even a visual video may help with that...IDK. Clunk sound like metal to metal or a rattle of some sort?

I like your suggestion.

Ironically, I had planned to record the clunks with my iPhone and video the right and left wheels in slow motion while standing opposite a test bump as my wife drove over it, to see if there is a noticeable difference in the right and left wheel movement. But we had some much needed rain which postponed the project. I’ll try again tomorrow.

FWIW I’ve gone back to Plan A. I ordered a pair of Bilsteins and the orange squishy bits from ECS tuning. They should be here some time next week. They’d be here earlier but the orange bits are BMW parts which may take an extra 4 days. Meanwhile I’m going back under to drop the heat shield panels and verify that the center drive shaft bearing is secure.

Funf Dreisig

[Gregory891]

Suggestion = put your year and model in your signature, it helps to (after a few pages on the forum) to remember these details.

Did you swap wheels (side to side) to eliminate wheel or tire damage?
Did you remove the CV shaft - a bit more work but you eliminate this as well?
You could swap shocks (side to side) before buying a pair. I have yellow B6 on my E53, firmer but no regrets.

Having needed the replace my four rear axle carrier bushings, you'll get a clunk over speed bumps, imperfections, sometimes feel a slam sensation. Less intense with 17", more so with 18" (my two wheel sets).

It might appear to be "too soon" but the pothole might have done this. In my case, visual inspection didn't reveal or indicate damage BUT upon assembly - EACH of the four bushings came out in two pieces. My case was simply the march of time - it's a necessary item on the E53. The E70 design appears to be quite similar.

[FunfDreisig]

Originally Posted by Gregory891

....Did you swap wheels (side to side) to eliminate wheel or tire damage?
Did you remove the CV shaft - a bit more work but you eliminate this as well?
You could swap shocks (side to side) before buying a pair. I have yellow B6 on my E53, firmer but no regrets.

Having needed the replace my four rear axle carrier bushings, you'll get a clunk over speed bumps, imperfections, sometimes feel a slam sensation. Less intense with 17", more so with 18" (my two wheel sets).

It might appear to be "too soon" but the pothole might have done this. In my case, visual inspection didn't reveal or indicate damage BUT upon assembly - EACH of the four bushings came out in two pieces. My case was simply the march of time - it's a necessary item on the E53. The E70 design appears to be quite similar.

I haven’t swapped wheels. But I’ve done a good visual inspection.
I haven’t removed any of the suspension except the right rear shock and sway bar, with no change in the clunk with either removal.

I’m replacing the shocks (with B4 Bilsteins) because they are wear items and we have used the X5 to tow heavy loads (e.g. 2 cubic yards of crushed limestone) in our 5 ton capacity utility trailer.

Did you replace the rear axle carrier bushings on your E53 yourself?
Did you do it with the rear axle carrier still on your E53?
Did you use one of the special tools to get the bushings out?
Were the bushing fractured vertically or horizontally?

FWIW it is easy to find special tools for removing E53 rear axle carrier bushings while still on the vehicle. But I didn’t find any for the E70. Which left me wondering if a special tool is not needed (i.e. too-easy / not-possible)?

Funf Dreisig
2009 E70 X5 35d

[Gregory891]

Again - this is for the E53 - but to answer to Funf Dreisig's questions:

Did you replace the rear axle carrier bushings on your E53 yourself? YES

Did you do it with the rear axle carrier still on your E53? You do one side at a time. There are 2-3 good Youtube videos that outline this, but do NOT remove or cut your exhaust hangers - they serve a purpose. You can carefully bend them just a bit for clearance.

https://www.youtube.com/watch?v=grTMssDU-iw THIS SHOWS HOW TO DO IT

A second one (can't find the URL) shows it with the tool that I used.



Did you use one of the special tools to get the bushings out? YES - I used the custom set (I've seen 2-3 different ones). Buy the one with the three shiny cups - it works rather well.

Were the bushing fractured vertically or horizontally? The inner metal insert was no longer bonded to the rubber or the outer ring. Same case for ALL four. The car is now a pleasure to drive. I used Meyle HD bushings.

E70 - this isn't as well documented. Not many resources (yet). I'd suggest you buy a Bentley manual to see what they recommend.

[FunfDreisig]

Originally Posted by Gregory891

Again - this is for the E53 - but to answer to Funf Dreisig's questions:

Did you replace the rear axle carrier bushings on your E53 yourself? YES...

Thanks for the link and explanation of how you fixed your E53’s rear axle carrier bushings.

It’s pretty easy to find the E70 rear axle carrier bushing parts # 33316784940. But I still can’t find any info on an E70 rear axle carrier bushing tool.

And I haven’t found any posts by people who have had problems with the E70 rear axel carrier bushings. This is a little surprising since the E70s have been on the road for over a decade. So I’m going to wait until I have the new shocks installed before I pursue replacing the bushings.

Funf Dreisig
2009 E70 X5 35d

[FunfDreisig]

If anyone is curious. I spent some quality time under the X5 today dropping the plastic panels under the gas tank and the heat shield over the exhaust to check out the last potential source of the clunk that could have serious consequences while I wait for the shocks.


The bearing and U joint in the middle of the driveshaft look good and have no play.

Talon Dancer
2009 E70 X5 35d

[FunfDreisig]

The new rear shocks arrived this afternoon and I installed them. No joy. The clunk stayed the same

I've used the time waiting on the shocks to search for info on replacing the rear axle carrier bushings. There is plenty of info & tools for E53s and other BMW models. But I found no info or tools for replacing the rear axle carrier bushings on an E70.

Please post if you have any info on replacing the rear axle carrier bushings on an E70. For example, does the tool used on E53 bushings work with the E70?

Funf Dreisig

p.s. The old shocks were not “preloaded” — I easily removed them off without jacking up the rear. But the new Biilstein B4s required raising the rear end so the tires were off the ground.

[FunfDreisig]

This is the difference in the static length of the original shocks and the B4 Bilsteins. The difference is the “preload” which required raising the X5 to fully extend the suspension for installation.

Funf Dreisig

[FunfDreisig]

I removed the right rear subframe radius rod to inspect the bushing. It is made differently than the E53’s. But it appears that the function is the same. The bolt ties the metal center of the bushing to the frame of the car and radius rod. And the outer rubber cylinder is press fit into the subframe. When the bushing fails the flexible part of the bushing breaks and allows the subframe to “float”. On bumps the subframe moves up and down allowing the rubber bushing stoppers to bounce between the frame and the radius rod. I think this is what produces the clunk sound. The bigger the bump the more times the subframe bounces between the frame and the radius rod.

I suspect the broken bushing is the right front. But it is harder to get to because of the plastic panels under the fuel tank. Since I couldn’t find a special too for the E70 to pull and reinstall the bushings I’ve set up an appointment at the shop.

Funf Dreisig
2009 E70 X5 35d

[FunfDreisig]

It turns out that it is harder to find a clunk-in-the-trunk, when the culprit is hiding under the hood

Attached is a photo of the top of the right front strut/shock absorber with the telltale orangey powder of the disintegrated upper guide support and 2 closeups taken with a WiFi inspection camera.

A pair of Bilstein B4 front struts/shocks, all the BMW orange bits and a spring compressor, are due next week. While I have the front end up on stands, I’ll replace the front brake pads with a set of Akebono EUR 1294 ceramic pads.

Funf Dreisig