[roamer]

Gang-

About 4 months ago I had a Wavetrac installed in my 335i - 6sp.. Ever since the install there has been an intermittent "clunk" when putting the car in gear or on hard shifts. I went back to the shop and complained and they claimed they checked the backspacing and it was "fine". Notably, they did not have/use spacers during the install.

Is there any way I can check if it is a backspacing issue without taking the diff out? When I turn the driveshaft with the rears off the ground there does not seem to be much play.

Could it be something like a loose or worn driveshaft mount/bushing or possibly a problem with the diff itself?

Any help would be appreciated!

[zsapphire7]

make sure the 50mm nut that connects the drive shaft to the pumpking is greased up and tight.

[roamer]

z-

Thanks, I will give that a shot! Is it greased through a zerk fitting or just slopped on there?

[zsapphire7]

slopped on the teeth gears.

[dzenno]

roamer, did you figure this one out?

zsapphire7, did you also have this same issue?

[zsapphire7]

i did long long ago but i dont have it anymore. I dont have the factory torque specs on that bolt but ive heard it was somewhere around 200lbft. After tightening it as much as i could the clunking was gone.

[HP Autosport]

Originally Posted by roamer

Gang-

About 4 months ago I had a Wavetrac installed in my 335i - 6sp.. Ever since the install there has been an intermittent "clunk" when putting the car in gear or on hard shifts. I went back to the shop and complained and they claimed they checked the backspacing and it was "fine". Notably, they did not have/use spacers during the install.

Is there any way I can check if it is a backspacing issue without taking the diff out? When I turn the driveshaft with the rears off the ground there does not seem to be much play.

Could it be something like a loose or worn driveshaft mount/bushing or possibly a problem with the diff itself?

Any help would be appreciated!

Did you get this problem resolved?

[roamer]

Not yet Harold. Any ideas?

[Funkmob]

I seem to be having this with my Quaiffe , i have this thumb/clunk when i come to a standstill. Also hear and feel it when i start moving again. Shop also had no shims so its been installed as is.

[HP Autosport]

Originally Posted by roamer

Not yet Harold. Any ideas?

Was it a complete Wavetrac final drive or just the Wavetrac only?

[dzenno]

After I broke one of my rear half shafts recently, go them fixed and upgraded by DSS, clunk is gone...I also had a vibration between 2500-3000rpms on decel...both issues gone with new halfshafts...

[techlogik]

For the 20 guys in the Wavetrac LSD groupbuy...hope this isn't an issue.

They are doing a complete pumpkin/diff swap since mine is welded at Wavetrac..so hopefully they get that part right, then my local shop just needs to swap the pumpkin.

Will update the results in the next few weeks.

But, I will say this, the E46 M3 LSD clunked all the time...it was the nature of how it was made and operated...some people tried different Diff fluid to help..but it was always there on my SMG.

[dzenno]

I can tell you that mine is gone 100% after the halfshaft change...don't know how but its gone...seems to be mostly with 6MT quaife/wavetrac units, not 6ATs which have the torque converter to muffle tons of noise..

[BlakeAction]

So, being one of those 20 in the Wavetrac groupbuy....is there anything I should tell my local shop when I go to get it installed on my 6MT? Sounds like new half shafts are part of the issue....I've heard some things about shims, etc....any helpful hints?

[nestillo335i]

Originally Posted by dzenno

I can tell you that mine is gone 100% after the halfshaft change...don't know how but its gone...seems to be mostly with 6MT quaife/wavetrac units, not 6ATs which have the torque converter to muffle tons of noise..

So, this issue should not affect 6At? Hopefully not, because my diff is coming
this week and if my wife listen something weird she will me

[roamer]

Originally Posted by BlakeAction

So, being one of those 20 in the Wavetrac groupbuy....is there anything I should tell my local shop when I go to get it installed on my 6MT? Sounds like new half shafts are part of the issue....I've heard some things about shims, etc....any helpful hints?

Yeah, a couple of things. First, be sure to have shims and adjust the backlash to Wavetrac specs which are a fair amount tighter than BMW's. Second, be sure to change the diff fluid after a few thousand miles and stick with the OEM fluid (non-slip additive).

[roamer]

Originally Posted by dzenno

I can tell you that mine is gone 100% after the halfshaft change...don't know how but its gone...seems to be mostly with 6MT quaife/wavetrac units, not 6ATs which have the torque converter to muffle tons of noise..

What and how were the halfshafts broken? I don't do any hard launches, so I would have a hard time believing that is the source of my clunk. Let me know so I can have the mechanics take a look. Thanks.

[BlakeAction]

Great! Thanks, I'll make sure I stay on the shop and make sure they get the backlash right. Sounds like that was the problem on some of the other threads too. I'll get the fluid changed out too, just to make sure everything is running right.

Originally Posted by roamer

Yeah, a couple of things. First, be sure to have shims and adjust the backlash to Wavetrac specs which are a fair amount tighter than BMW's. Second, be sure to change the diff fluid after a few thousand miles and stick with the OEM fluid (non-slip additive).