[sav_e92]

My new-to-me ‘07 328xi has some slop in the driveline that is causing clunky shifts, particularly in lower gears and when hitting the gas at speed. I was thinking of looking into the following parts as possible culprits but was wondering if anyone has experience tracking down similar symptoms:

Guibo
Motor/trans mounts
Diff mounts/bushings
Transfer case mounts/bushings
Rear subframe bushings

I’ve seen a lot of discussion of rear subframe bushing failure on this forum and was wondering if anyone had used these or knows how they compare to power flex inserts?

Anything else I should consider?

[wuoltk]

Check the center carrier bearing also

[sav_e92]

Originally Posted by wuoltk

Check the center carrier bearing also

Good call.

[matteblue3er]

I just replaced my motor mounts and shifting is night and day.

I just did a manual trans swap and after doing so, power delivery felt as if I was using a rubber band between the trans and engine. After doing mounts, power delivery is solid. Had 131k on the drivers, passenger which takes more load was replaced around 80k miles. Both were stiff when I took them out so at first; I thought it wasn't going to make a difference but it completely solved that disconnected feeling I was getting.

I used 034 Motorsport 50A mounts. FWIW, I also have a solid aluminum transfer case mount.

I've never used those 034 motorsport subframe inserts but in theory, they should be better than those poly inserts you see. These seem to lockdown the inner metal section with the rest of the subframe/chassis. Similar to how my transfer case mount by Twisted Tuning works.

Btw xDrive models do not have trans mounts. There is only the transfer case mount

[sav_e92]

Originally Posted by matteblue3er

I just replaced my motor mounts and shifting is night and day.

I just did a manual trans swap and after doing so, power delivery felt as if I was using a rubber band between the trans and engine. After doing mounts, power delivery is solid. Had 131k on the drivers, passenger which takes more load was replaced around 80k miles. Both were stiff when I took them out so at first; I thought it wasn't going to make a difference but it completely solved that disconnected feeling I was getting.

I used 034 Motorsport 50A mounts. FWIW, I also have a solid aluminum transfer case mount.

I've never used those 034 motorsport subframe inserts but in theory, they should be better than those poly inserts you see. These seem to lockdown the inner metal section with the rest of the subframe/chassis. Similar to how my transfer case mount by Twisted Tuning works.

Btw xDrive models do not have trans mounts. There is only the transfer case mount

Thanks for that input. I'll see if I can visually check the motor mounts by revving up while holding the e-brake and will judge the motion there. I'm thinking that its more likely to be the transfer case mount (thanks for the tip on the xi not having trans mounts) or the subframe just based on where I feel the clunk but definitely won't rule out the motor mounts.

Did you notice any increased NVH with the harder mounts or solid t-case mount?

[matteblue3er]

Originally Posted by SAVAGE_VT_E92

Thanks for that input. I'll see if I can visually check the motor mounts by revving up while holding the e-brake and will judge the motion there. I'm thinking that its more likely to be the transfer case mount (thanks for the tip on the xi not having trans mounts) or the subframe just based on where I feel the clunk but definitely won't rule out the motor mounts.

Did you notice any increased NVH with the harder mounts or solid t-case mount?

Motor mounts, no. Replacing my mounts actually decreased vibration at idle.

Transfer case mount, yes. There is increased vibration at idle. My E90 is not a daily driver so I don't mind

[sav_e92]

So I ended up installing whiteline RFSB inserts and they definitely took the edge off of the clunky shifts but they are not completely. Based on where I feel the clunks I’m thinking more that this is related to the guibo or t-case mount vs the motor mounts. I’m now debating whether this job is worth the $600 or so my local shop is quoting to do the work... if I had to start with one of the two, which would make more sense? Is that quote crazy?

[Boosted12a]

Yes, expensive. You can get the tools you need and parts for less than that.

[sav_e92]

Originally Posted by Boosted12a

Yes, expensive. You can get the tools you need and parts for less than that.

Yeah I wouldn’t hesitate to do these myself but I don’t have a great setup for getting under the car. I think I would need some taller jack stands and a more serious floor jack than what I’m working with now to get in there. Or a quickjack...

[Boosted12a]

Once you have the tools they will pay for themselves quickly. Has your water pump been replaced yet? You will save yourself about $500 doing it yourself when it goes. $200 for a good Jack and $35 for stands. They will last decades even if you abuse them.

[e90_enjoyer]

Did you ever figure this out? Having similar issues on a rwd 330i, hoping it’s not the flywheel lol

[AWD Addict]

I did my motor mounts a couple years ago, and the driveline slop was completely eliminated. One was def damaged.