Danny's Japan Rot 540i Touring Thread

[dannyzabolotny]

Yeah, I've had that Porsche 944S forever. I just kinda lost motivation to work on it recently since I got some new stuff to put on the wagon. The wagon's always my favorite to work on so it gets the priority. And then the X5 keeps having stuff break so that's kept me busy.

Lastly, I'm trying to figure out what I want from my YouTube channel, which is why I haven't been posting any new videos. I don't want to do boring car vlogs like a lot of guys do, but I also don't want to be filming full on DIYs because a) it's already been done a million times and b) I have no patience for that much filming, it makes projects take 5x as long. I guess I'm trying to figure out the right mix of information and entertainment. The past videos I've made have been kinda long and rambling, so I'd like to avoid that.

[computiNATEor]

B is for Build or Home Built by Jeff styles are enjoyable to me. But if you don't want to do it, don't. Just do what comes naturally to you.

[dannyzabolotny]

To catch this thread up on my car's progress: https://www.bimmerforums.com/forum/s...eling-Inactive

Basically my self leveling suspension in the rear stopped working after I did my rear suspension refresh. I checked for errors with INPA and found that the rear right sensor was having issues. I swapped in another sensor from the 2001 540it parts car in my backyard, but that didn't fix anything. I drove around with the self leveling system not working for two weeks— no real problems aside from the blinking error message. My air springs hold air pretty well I guess.

Now before all you air suspension haters come out of woodwork, the fix ended up being pretty simple. I bought a new ride height sensor from AutohausAZ, it was the OEM one for $60. It turned out to be the BMW sensor but with the BMW logo ground off, so good deal there. I installed the new sensor and the problem went away during the first test drive. So far the error has not come back, so I'm counting that as a success!

During that time I also dropped off my rear wheels at a wheel shop in town to have them checked for bends since I have some pretty bad vibrations coming from the rear. They checked them on a roadforce balancer and said the wheels were completely straight. The issue is with the tires, both of the tires in the rear have some pretty bad defects that prevent them from balancing out properly. The tires are Continental Extremecontact DW, I got them on clearance from Tire Rack a little under a year ago. The rear tires are pretty worn too, especially on the inner parts. I've got about 13,000 miles on the tires, but I guess since I drove with a bad rear suspension for so long they wore out quicker. I swapped on a set of wheels I had laying around from the parts car, the tires on them were complete garbage but I noticed that I had waaaaay fewer vibrations with them, so it's definitely a wheel/tire related issue.

Apparently running them with more air helps with wear? I always had my tires around 32 psi all around, so last night I inflated them to 38 front and 41 rear. The car certainly handles better but man there's a lot of harshness.

To add to that, something in the front suspension must have gone bad, because I now get the 50mph steering wheel shimmy again. My suspicions are that the front thrust arm bushings have gone bad again. I'm going to get the car up in the air tonight to inspect everything. Maybe something came loose over the last year, I installed all new control arms in the front about a year ago, with 181k miles on the car. Could my bushings have gone bad in only 14k miles? Granted, the roads where I live are complete garbage, and I do drive my car like a maniac.

[auaq]

Yep, just get new rear tires and your vibrations will go away. Change the fronts too if they're bad as well. Might lessen the vibrations you're getting in the steering wheel, but it does sound like the thrust arm bushings are going bad with your aggressive driving style along with bad roads over there.

[dannyzabolotny]

Yep, just get new rear tires and your vibrations will go away. Change the fronts too if they're bad as well. Might lessen the vibrations you're getting in the steering wheel, but it does sound like the thrust arm bushings are going bad with your aggressive driving style along with bad roads over there.

My fronts are pretty good actually. They're Hankook Ventus V12 Evo2's and they've barely worn down since I had them installed, which was a long time ago (I got them several months before I got the Continentals for the rear). I'll probably get Hankooks for the rear, since I've been happy with them in the front. I haven't felt any of the 70-80mph vibrations from the front, all of that seems to be coming from the rear.

How long are thrust arm bushings supposed to last? And what's a good way to check if they're bad, aside from visually looking at them? Deflecting them with a pry bar to see if there's excessive movement?

If the thrust arm bushings are indeed bad, I'm not too worried since I ordered all of that stuff from FCP Euro. Lifetime warranty ftw!

[auaq]

Prying/twisting it is one way to tell if they appear loose. Another is fluid leaking from the bushings. If there is a presence of wetness around it then it's bad. Try MeyleHD instead of Lemforder.

[philly98540]

Go Meyle HD made for the X5. Beefier than the Meyle HD made for the 540.

[dannyzabolotny]

Go Meyle HD made for the X5. Beefier than the Meyle HD made for the 540.

Are the control arms the same between the two?

[WBAD530i]

I think it only applies to the bushings to press them in 540 arms

[philly98540]

Are the control arms the same between the two?

No. Just bushings.

[computiNATEor]

Or you could go for a set of German Auto Solutions monoballs and never have to fight the bushings again - assuming the ball joints hold up.

[auaq]

Or you could go for a set of German Auto Solutions monoballs and never have to fight the bushings again - assuming the ball joints hold up.

Yeah, that's another option. How much are they?

[dannyzabolotny]

Eh, the monoballs cost money, whereas getting the thrust arms replaced by FCP Euro is free aside from the return shipping. Since I've already paid for that lifetime warranty by buying from FCP Euro, I intend to use it until they go out of business, or my car explodes. Whatever comes first :P

Also, isn't there a lot more NVH with poly and monoballs?

[purplecty]

Just go with Meyle HD thrust arms... Im going to purchase from FCP as well for my e38. I had them on my 98 e38 for over 75k and the steering was non existent after i rebuilt the front end with all meyle...

https://www.fcpeuro.com/products/bmw...1121092610my-1

https://www.fcpeuro.com/products/bmw...-31121092610my

[auaq]

Eh, the monoballs cost money, whereas getting the thrust arms replaced by FCP Euro is free aside from the return shipping. Since I've already paid for that lifetime warranty by buying from FCP Euro, I intend to use it until they go out of business, or my car explodes. Whatever comes first :P

Also, isn't there a lot more NVH with poly and monoballs?

Apparently not according to those who have them installed. I, too, thought about NVH but seems like they are quiet.

- - - Updated - - -

But yeah .. I would just get the X5 MeyleHD bushings and press those in..

[computiNATEor]

Yeah, that's another option. How much are they?

$$$. Like $275 without the control arms.

[dannyzabolotny]

Tonight I finally stopped being lazy and jacked up the touring to find out why I've been getting that 50mph shimmy. As soon as I had the car up in the air, I saw what had happened:





Both of my thrust arm bushings had leaked out, with the driver's side one being way worse. This is particularly disappointing, considering that both thrust arms are new Lemforders that I bought and installed about a year ago with 181k miles. They only lasted one year and 14k miles, how sad. I guess Lemforder's quality control has gone downhill since the days of them supplying the original parts that these cars came with. Both were installed and torqued correctly, by the way.

Granted, I do drive my car a bit harder than most E39 owners, taking speed bumps and horrible road surfaces at excessive speed. The roads around my neighborhood are pretty awful too, since I live in a semi-ghetto part of town. I can pinpoint exactly when these bushings failed— about two weeks ago I had a fairly stressful Friday at work, so after work I did a burnout in my company's parking lot (good stress relief). Right after that, I noticed that something was up with the front suspension, it was an immediate difference. And then I proceeded to go drag racing on these bad thrust arms, getting a respectable 14.96 in the quarter mile and doing way more burnouts than necessary with street tires.

Thankfully I bought all of the suspension components at FCP Euro, so I'll be exchanging them for a set of Meyle HD thrust arms. We'll see if those work out any better. A lot of people suggested the X5 bushings, but I don't want to go to the effort of pressing bushings in and out, especially when I can get a set of Meyle HD thrust arms for free.

[geargrinder]

That blows Danzo. Totally weak. I'm pretty sure if you call FCP will happily give you credit towards the X5 HD bushings, then you can press those into your otherwise new arms (assuming other end is still ok).

[philly98540]

Sad that Lemforder sold out on us. Total crap TAB now. I wonder what other parts in their lineup are worthless too.

You should be good with the HD's. No brained to not mess with pressing in the HD X5 ones since FCP will be sending free replacement E39 ones.

[M73PWR]

Did you torque them down under load?
This sucks to hear because I’m in the process of suspension refresh on my e38 and I went with Lemforder instead of Meylr HD since I figured OEM lasted this car for almost 20 years so we should be good lol

[dannyzabolotny]

That blows Danzo. Totally weak. I'm pretty sure if you call FCP will happily give you credit towards the X5 HD bushings, then you can press those into your otherwise new arms (assuming other end is still ok).

I'm just gonna get the Meyle HD arms, much easier than messing with bushings.

Sad that Lemforder sold out on us. Total crap TAB now. I wonder what other parts in their lineup are worthless too.

You should be good with the HD's. No brained to not mess with pressing in the HD X5 ones since FCP will be sending free replacement E39 ones.

Yeah, I'm wondering that too... I did my whole suspension with Lemforder parts because everyone said they were the best. Hopefully it's just the thrust arms that suck. The other control arms looked okay when I checked last night.

Meyle HD arms will be the way I go. I have Meyle HD subframe bushings in the rear and they've been quite solid (pun intended?). Liquid-filled bushings are for old men that never beat on their cars.

Did you torque them down under load?
This sucks to hear because I’m in the process of suspension refresh on my e38 and I went with Lemforder instead of Meylr HD since I figured OEM lasted this car for almost 20 years so we should be good lol

Yep, I dropped the car down on ramps to torque them. I used to think OEM was the way to go, but I'm not the only one who's had issues with the new Lemforder stuff. I think they switched to cheaper materials at some point.

The only other thing I can think of is that I lowered my car like 6 months after installing the new thrust arms. I only lowered it like an inch in the front with Dinan springs, should I have loosened and re-torqued the bushings? I've never heard of anyone needing to do that unless they were going super stance low.

[auaq]

Yeah, it's sad that Lemforder are not Lemforders anymore.

Where are you getting the MeyleHD's from? I did not see one anywhere on FCP Euro and ECS Tuning.

[dannyzabolotny]

Yeah, it's sad that Lemforder are not Lemforders anymore.

Where are you getting the MeyleHD's from? I did not see one anywhere on FCP Euro and ECS Tuning.

I ordered them from FCP Euro, they're clearly there:

Left: https://www.fcpeuro.com/products/bmw...1121092610my-1
Right: https://www.fcpeuro.com/products/bmw...-31121092610my

[auaq]

Oh ....

[computiNATEor]

The only other thing I can think of is that I lowered my car like 6 months after installing the new thrust arms. I only lowered it like an inch in the front with Dinan springs, should I have loosened and re-torqued the bushings? I've never heard of anyone needing to do that unless they were going super stance low.

Yes, you should loosen and retorque the bushings any time the ride height changes. Otherwise, the bushings increase spring preload, and if you're lowering the car, will increase the effective spring rate and wear out more quickly.

But my experience with "Genuine BMW" control arms (aka Lemforder) was similar to yours. My mechanic installed them around ~96k on my black 530i; there was significant steering wheel wobble at 106k that alignments, tire balancing, and new straight arms didn't fix.

Another factor to consider is modern tires. When these suspensions were developed, the factory M5 tire was a Dunlop SP Sport 8080E; a tire, that, at best, would be equivalent to a high-performance all-season today. Modern max performance summer tires (Michelin PSS/PS4S, Conti DW, Hankook Evo2) have a TON of grip, and are going to distort the bushings harder and for longer than the engineers probably intended.