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Discussion Starter #1
So, when I redid the whole suspension I of course replaced the complete thrust arms with new Lemforder parts. Torqued them down with the weight of the car on the wheels on ramps. . . and they leaked in like 300 miles.
FCP Euro nicely sent me replacements, swapped them, and those too leaked (both sides, proper torquing down procedure followed) after about 500 miles.
So I just upgraded to the Syncro Design monoball bearings in order to be done with those miserable hydrobushings. . . but now the NVH transmitted from the wheels is really more than I want, with no rubber left isolating the knuckle from the subframe.
SOO. . . is there any other/better option out there? This is starting to get disheartening. . .
Thanks for any suggestions!
 

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You could go with X5 bushings. Surprised you feel that much NVH with the SWDs though. I have them on one of my M5s and I love them...
 

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Discussion Starter #3 (Edited)
Are the X5 bushings still hydro-filled bushings or 'regular' rubber? Maybe I'll give the spherical bearings a little longer and see how they feel with new tires in a bit, but so far they really seem to transmit the small/high frequency stuff from the front wheels quite a bit.
 

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Hmm. I just installed the SDW monoballs with the full refresh kit for front and rear, along with powerflex subframe insertsand Jed's unicorn egg in the front mount of the diff.

On original shocks (03 / 84k miles) and springs, with <6 months old Michelin PS4S inflated to recommended tire pressures on door jamb - I actually noticed zero NVH, and all this internet stuff really got me worried that I might feel it and/or hate it. It took me 3 weeks of random nights to do the install, and just got it off jackstands yesterday to an alignment shop. Today's driving was several long sweeping freeway turns at near triple digits, and my wife & toddler were fast asleep in the back.

All of the bushings I replaced were in great condition (all original), with only the rear upper control arm and guide link had busted ball joints - but the bug of "while you're in there" bit me. I don't track my car, just want a nice comfortable ride and if my wife noticed it was harsher, she'd definitely kill me. I realize this doesn't really help, but at least provides another datapoint. As a side note, if you refreshed the front, was your steering link recalled? If so, you'll want to replace that.
 

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When you say you put the car on ramps; did you drive the car onto the ramps, or just lower it onto the ramps? Was the rear of the car also on ramps too? If you just drop the car onto the ground/ramps there is still binding in the suspension that needs to be unwound by rolling the car.

I have the Synchro design monoballs as well with everything else being all OE+OEM and there is increased NVH in city driving.
 

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Are the X5 bushings still hydro-filled bushings or 'regular' rubber? Maybe I'll give the spherical bearings a little longer and see how they feel with new tires in a bit, but so far they really seem to transmit the small/high frequency stuff from the front wheels quite a bit.
Meyle HD bushings are the decent alternative too - those are rubber ones, not fluid filled. Arms with HD bushings were on sale recently at ECS.
 

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Seems odd to me that OE factory installed bushings can go to about 60-80K miles and be fine, but you are destroying them in several hundred miles? installer error, must be.
 

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Seems odd to me that OE factory installed bushings can go to about 60-80K miles and be fine, but you are destroying them in several hundred miles? installer error, must be.
My new Lemforder bushings failed in 8,000 miles too, something is happening with that brand lately. If you noticed FCP is recalling Lemforder center steering link.
 

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Discussion Starter #15
installer error, must be.
I'm not above admitting that this is possible, but I think it unlikely for several reasons. Firstly, I was aware of the need to have the car at proper ride-height before tightening them down, so I took the height measurements before dismantling the car. The first time I just jacked each corner to the proper height and then tightened the fasteners. This worked great on the 540i I did several years ago, whose bushings are still in fine shape some 20,000 miles later. The second time, after the initial failure, I went the extra mile of driving around the block and then up on to the ramps to make sure it was really settled and correct, (though I only put the front up, not the rear). I find it hard to believe that such an infantile failure could occur after the diligence I put in without some sort of additional factor being present; they just can't be THAT fragile in general! For posterity, here they are at removal.
932901

932900


As a side note, if you refreshed the front, was your steering link recalled?
Yes it was, and this is in fact the reason I decided to try the SDW bearings; I replaced the recalled center link and put in the new thrust arms at the same time.

At the end of the day, I think I'm going to stick with the spherical bearings a while longer. They're really not bad, but I think I have a small wheel or tire issue that is more easily felt (especially at highway speeds) through the new links. I did just have the tires balanced and the alignment done after replacing the center link, but I think either a dynamic road-force balance or new tires will likely clear up most of my lingering complaints, and I'll wait to see how everything feels again after that. Thank you though for the protection package and Meyle HD bushing information; I'll keep those options in mind if I ever decide to revisit these dumb links yet again!
 

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Thanks for the update, I was truly worried I would hate any type of increased NVH, as each car is slightly different - I'm lucky I saw no ill effects. I do however have a high-pitched wind/tire type noise, which isn't arm related (or it doesn't sound like that), that might be solid diff mount related or who knows. I didn't even notice it but my wife said "what is that sound?" so I have further investigation. Oh well, makes me drive the car at high speeds.
 

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Timely post, I am battling through something similar. My original thrust arms have 40k on them and needed replacement badly. Based on forum discussions I sprang for a set of GAS monoballs. they feel amazing driving around on the highway. Problem is I live in a city... sharp transitions such as potholes and choppy pavement are very common and the NVH is pretty annoying when driving around on city streets. I think that's why there is such a wide range of experience with monoballs, they only transmit a very specific type of vibration which i believe is caused by square edge hits (highway markers are often sighted). You can have 2 similar sized bumps but if one has a square edge and the other a smooth edge, it makes all the difference with monoballs. Following this thread closely to figure out next steps. I bought some lemforder bushings on ebay and was going to press them in but would love to find an oem-like solution that can go the distance.
 

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I'm not above admitting that this is possible, but I think it unlikely for several reasons. Firstly, I was aware of the need to have the car at proper ride-height before tightening them down, so I took the height measurements before dismantling the car. The first time I just jacked each corner to the proper height and then tightened the fasteners. This worked great on the 540i I did several years ago, whose bushings are still in fine shape some 20,000 miles later. The second time, after the initial failure, I went the extra mile of driving around the block and then up on to the ramps to make sure it was really settled and correct, (though I only put the front up, not the rear). I find it hard to believe that such an infantile failure could occur after the diligence I put in without some sort of additional factor being present; they just can't be THAT fragile in general! For posterity, here they are at removal.
View attachment 932901
View attachment 932900


Yes it was, and this is in fact the reason I decided to try the SDW bearings; I replaced the recalled center link and put in the new thrust arms at the same time.

At the end of the day, I think I'm going to stick with the spherical bearings a while longer. They're really not bad, but I think I have a small wheel or tire issue that is more easily felt (especially at highway speeds) through the new links. I did just have the tires balanced and the alignment done after replacing the center link, but I think either a dynamic road-force balance or new tires will likely clear up most of my lingering complaints, and I'll wait to see how everything feels again after that. Thank you though for the protection package and Meyle HD bushing information; I'll keep those options in mind if I ever decide to revisit these dumb links yet again!
WOW!, that's a pretty spectacular failure. I agree based on how you did the loading you shouldn't have had this failure unless your ramp were obscenely tall.
Timely post, I am battling through something similar. My original thrust arms have 40k on them and needed replacement badly. Based on forum discussions I sprang for a set of GAS monoballs. they feel amazing driving around on the highway. Problem is I live in a city... sharp transitions such as potholes and choppy pavement are very common and the NVH is pretty annoying when driving around on city streets. I think that's why there is such a wide range of experience with monoballs, they only transmit a very specific type of vibration (highway markers are often sighted). So some driving environments can be rough but devoid of sharp impacts, while other (urban) ones are full of them. Following this thread closely to figure out next steps. I bought some lemforder bushings on ebay and was going to press them in but would love to find an oem-like solution that can go the distance.
Take pictures of the ebay bushings, including all stamping. This will either turn out to be a be an FCP issue or a global lemforder issue.
 

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I swear it's a lemforder issue. I busted 2 pairs on my E39 10k-ish miles and another in 3-4k afterwards over the course of a few years. I said screw it and went with mooseheads, definite increase in NVH, but soooo worth it for that solid steering wheel.

My E53 made a pair last a solid 40k back from 2015'-18' or so, but then blew 1 in under 15k. (I had FCP this time though :) ). But there is a definite quality control issue at the manufacture level, I'd bet the increased incidence rate would correlate to the transition to China production over germany.
 

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Discussion Starter #20
But there is a definite quality control issue at the manufacture level, I'd bet the increased incidence rate would correlate to the transition to China production over germany.
Thanks, my thinking is certainly trending along these lines as well, and it's reassuring to hear that I'm not the only one! Thanks for sharing!
 
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