Question regarding alignment/suspension components.

[Furreals]

I have a mild shaking/wobble between 53- 68mph according to speedo. <50 is smooth sailing 70+ super minimal shake but personally consider it negligible. I changed tires because was shown that I had a permanent flat spot causing the tire to wobble even though the wheel shows straight on balancer. This basically took it from insane shaking to what it is I mentioned upon first two sentences.

Afaik the suspension components up front are all good/newish

Overall I don't want to overhaul everything again so I do not mind living with the 53-68 shaking IF it isn't bad for the chassis/bushings/ etc? < confirm please if possible

Also my rear dog bones are kinda shot. They show cracks/rot < if this does not affect alignment or is it suggested I change these first.

Can I get a solid alignment disregarding ALL of these ? Or will the alignment be shit if I do not remedy any of these before alignment.

Also I have 15mm spacers coming in, should I wait to align with them on or can I align first and can put them on after.

Thanks

edit: I do have 5mm spacers in front torqued down with the OE size bolts (It is supposedly safe up to 5mm but no more.) to use OE length bolts. Not sure if this could be a possibility but it shouldn't. Eibach spacers sanded down both the hub, spacer, and wheel back.

[Spaceturtle917]

The shaking is more than likely your thrust arm bushings or ball joins. I'd recommend replacing both arms. They're easier than the lower control arms because you don't have to drop the strut plate. Grab one of these and some of these and it should be fixed. Hey while your at it you could do this instead of the spacers. The shaking may cause damage to the steering box and the tire wear may be bad. I wouldn't recommend widen your track width until you get the suspension fixed.

The pitman arms or "dog bones" will cause your car to steer itself in the rear and wander if warn out and will probably effect the alignment if worn out. Source

I would recommend fixing the shake. If your thrust arm and lower control arm ball joints look good then it's most likely the bushings. You said they were newish and if you did them yourself you want to make sure they were torqued to spec under vehicle load. If not the bushings will wear out pretty quick. Replacement bushings are pretty cheap if you want to rent a bushings press from autozone. You could even put e32 750i bushings in as they are more stiff and will handle better/last longer. Found here. More info on this found here.

[moroza]

On what basis do you judge the front end to be good/newish?

Spacers, sticky tires, or big wheels will exacerbate vibrations. I disagree with Spaceturtle; lower arms are easier to change because removing three bolts for the strut plate is far less work than torquing the uppers' bushing under load. Also, lowers in my experience cause steering slop but not vibrations. Thrust/uppers cause vibrations if worn, incorrectly installed, or crappy. If sticking with stock bushings, use OE or Lemförder parts only. See here for stock fitment info.

My experience is that about half of tire shops fail to detect out-of-round wheels or tires, either of which will cause a shake that's impossible to balance out.

The stock rear is unalignable. The only adjustment possible is front toe. You definitely want to do that *after* replacing any front end parts. If anything is actually loose, you won't get an accurate alignment at all.

[shogun]

Timm's BMW 50MPH - 60MPH SHIMMY, also applies to E34 http://www.meeknet.co.uk/e38/E38_Shimmy.htm

[fo3]

Are your spacers hubcentric too? I've got e39 16" wheels on mine and the vibration is terrible unless I use hubcentric rings.
I replaced all my suspension, then got new tyres and alignment but the first time I drove 90-100km/hr weeks later I thought a wheel was coming off or something in the suspension broke. Vibration was so bad I thought I was going to crash unless I pulled over. For the previous weeks I drove my car up to 70km/hr with no vibration problem.

It turned out the tyre shop tossed the old plastic hubcentric rings that were on there that e39 wheels needed. (E: I made that guess because the spare wheel had a plastic ring but none of the fitted wheels did - so the tyre shop must of thrown them out. Later on I confirmed this fact)
Manual centering by hand torqueing the bolts cross wise helped get me home and then I got some aluminium hubcentric rings from ebay that sorted the problem for good.

E: I have no idea what in the BMW susp and steering geometry really really needs this, as all my other cars just self centre with the bolts even though they were supposed to be hub-centric it didn't really matter - even at 200km/hr! But the e34 really needs hubcentric rings for 90km/hr smooth travel, for some reason. E: and IMHO if they're that fussy it's probably not a good car to put any kind of spacer on.

[ross1]

" lower arms are easier to change because removing three bolts for the strut plate is far less work than torquing the uppers' bushing under load"
moroza, I'm not following you here
OP, agreed that something you've assumed good is not

[moroza]

Unless done on an alignment rack, reaching the thrust arm bushing bolts to tighten them under load is far more a PITA than removing the three bolts holding the lower strut plate (steering knuckle) to the strut. But it doesn't matter - replace the part that needs replaced, not the one that's easier to do.

[Spaceturtle917]

That’s what ramps are for my guys.


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[Martinator]

If replacing worn front suspension parts, consider getting Mooseheadcontrol arm bushings. They're pretty great.

[ross1]

Unless done on an alignment rack, reaching the thrust arm bushing bolts to tighten them under load is far more a PITA than removing the three bolts holding the lower strut plate (steering knuckle) to the strut. But it doesn't matter - replace the part that needs replaced, not the one that's easier to do.

Feeling a bit stupid but I don't understand how unbolting the plate relieves you of tightening the through bolt while under load.
Ramps work fine for me too.

[Furreals]

Thanks for the responses and the links people. I will be reading through and hopefully pin point this issue.

I'm hoping for that it might be something simple as a mis-diagnosed wheel (was shown only the tire wobbled not the wheel before the new tires.) or the need of a hub centric ring.

Also good to know the E34 like the E23 is front toe only, can probably save a lot. My guy does 40$ front tow hopefully can still honor it as his rents going up.

The components including thrust around less then 10k mi.
The wheels are BBS or FUNDO RZ 469 16x8 +23 which came off a E38

eibach pro spacers

+5mm in front due to rubbing shock body
+15 in rear (no change)

[moroza]

Feeling a bit stupid but I don't understand how unbolting the plate relieves you of tightening the through bolt while under load.
Ramps work fine for me too.

It doesn't. The contention was that the uppers are easier to replace than the lowers, because removing the former is easier (you can remove the uppers' balljoints without removing the strut plate). I say that while that's true, this difference in removal difficulty is a lot less than the difference in installation difficulty, namely that torquing the uppers takes way longer than the lowers. Even with ramps, I've run out of room for a wrench big enough for 94ft-lb.

[Furreals]

Update: It turned out to be a wheel that was not true. I have since when to 10mm spacers in front and 15mm in back. I have put the wheel that was not true in the back right, somehow I do not really notice much shaking/vibrations. The front is now 90% free of any wobble/shaking it had previously.

Now, will the rear bushings/joints get worn due to the un-true wheel wobble/shaking? As mention so far I do not notice much shaking/vibration if at all and could be the roads.

I will take notice again when going to work tomorrow.

Thanks for all the insight and gained more reading material guys. Luckily so far don't seem to need to redo any front suspension I do have an odd creak in the back I now have to figure out... If this stands out to someone let me know

[moroza]

Now, will the rear bushings/joints get worn due to the un-true wheel wobble/shaking?

Not severely, but yes. Rear rubber seems quite sturdy, but if you let this go, I'd expect the rear shocks or wheelbearings to wear a bit prematurely.

I do have an odd creak in the back I now have to figure out... If this stands out to someone let me know

Could be a few things, but FWIW my horrible rear end creaking turned out to be the dogbones. Of course I confirmed that only after replacing subframe mounts and RTABs, all with OE parts. Dogbones are easy to diagnose (unbolt half of each one and go for a gentle drive), cheap (Rein Italy $13 each at FCP with lifetime warranty), and relatively easy to change. Make sure to tighten them with the suspension fully loaded, not in the air.

[Furreals]

I see, if I do not get a new wheel I wonder if by the time those bearings/shocks go out maybe close/or at time to change the rest perhaps. I'll use it as an indicator for the other bearings/shocks. just kidding, will preferably be sourcing a wheel or find out if I can get this wheel re-trued.

Will be looking into the rear end creak soon enough. I do also suspect the dogbones as they look old with slight cracks compared to anything else back there when I was changing wheels/spacers searching for the wobble.
Thanks

[Spaceturtle917]

Will be looking into the rear end creak soon enough. I do also suspect the dogbones as they look old with slight cracks compared to anything else back there when I was changing wheels/spacers searching for the wobble.
Thanks

The dog bones being worn out will make the rear wander a lot to. You might notice that you constantly have to correct the car.


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