[Johncaponegotti]

The first picture is my right rear tire the second picture is my left rear tire. For some reason there seems to be a bigger gap with the left tire than the right tire. It seems to me like I can barely manage to fit my index finger through the top of the right wheel well. But I can easily slide my finger on the left wheel. Any idea why this could be? When I drive slowly It seems to be as if something is loose or not right with the right rear tire.

[XutvJet]

You can take a take a tape measure and measure from the exact middle of the wheel cap to the bottom edge of the fender. This will give you the exact difference between the gaps.

With that said, there's nothing wrong with your car.

1) Cars have different weights at on each tire.

2) Springs are what suspend the car. Springs are simply wound steel. There are minor differences in the spring rate thus it's not uncommon for there to be a 1/4" or so difference at static ride height.

[Luftwaffe1O1]

You also need to make sure you are on completely level ground. Even minor variations can cause a big change. The spring holds the car up, so unless something else broke along the way, but really try to find as level of a spot as you can and park there, let it sit for a bit, and measure the exact gap per each corner.

[hwntime]

All the more reason to go with coilovers

[MarcoZandrini]

BMW engineers specify a slightly taller spring for the left side of the car. Why? Our cars are typically driven with only the driver in the car. So, with just a driver, the car’s ride height is equal on both sides. BMW has been doing this for decades.

[Johncaponegotti]

Originally Posted by MarcoZandrini

BMW engineers specify a slightly taller spring for the left side of the car. Why? Our cars are typically driven with only the driver in the car. So, with just a driver, the car’s ride height is equal on both sides. BMW has been doing this for decades.

Originally Posted by MarcoZandrini

BMW engineers specify a slightly taller spring for the left side of the car. Why? Our cars are typically driven with only the driver in the car. So, with just a driver, the car's ride height is equal on both sides. BMW has been doing this for decades.

Originally Posted by Luftwaffe1O1

You also need to make sure you are on completely level ground. Even minor variations can cause a big change. The spring holds the car up, so unless something else broke along the way, but really try to find as level of a spot as you can and park there, let it sit for a bit, and measure the exact gap per each corner.

Thanks guys. Maybe I'm just tripping thinking I'm feeling something bad while I'm driving. I do have a dinan suspension so that's why I was a little extra worried.

[overcoil]

Wasn’t there a story about bump stop sizing on Dinan spring ?

I’ll chk for an older thread


Guess I was mistaken couldn’t find any quality or mounting bump stop thread

[amw896]

are u xdrive? A lot of awd cars have this issue.

[designatedposter]

I had an issue with uneven height in the rear between driver and passenger side. I reinstalled both springs and determined it was because the spring perch was installed incorrectly on one side. It was either upside down, rotated, or something like that.

Check that out. Youll notice the spring perch is not symmetric and needs to be installed a certain way.

[Matthewricha]

Did anyone resolve this issue?

I have the exact same issue as the OP. I have M Performance springs. I am thinking this is an issue of factory uneven ride height which is exacerbated when lowered. I too feel the looseness of the OSR wheel to the point where I thought a bush had gone. I have a RHD car so I really feel it.

I've replaced most bushes and put poly subframe bushes in. . I have also fitted a 6mm spring shim, which only adjusted the height difference between NSR and OSR by 3mm.

I wonder if lowering causes even more preload on the antiroll bar? either non-neutral orientation of the bar or uneven loading side to side.

Similar threads:
https://f30.bimmerpost.com/forums/sh....php?t=1119748

specifically post 3:
https://f30.bimmerpost.com/forums/sh...08&postcount=3

My options are to either refit my original M Sport Springs to the rear (even though that still yield uneven height) or see if adjustable droplinks aid the issue.

[designatedposter]

Originally Posted by Matthewricha

Did anyone resolve this issue?

I have the exact same issue as the OP. I have M Performance springs. I am thinking this is an issue of factory uneven ride height which is exacerbated when lowered. I too feel the looseness of the OSR wheel to the point where I thought a bush had gone. I have a RHD car so I really feel it.

I've replaced most bushes and put poly subframe bushes in. . I have also fitted a 6mm spring shim, which only adjusted the height difference between NSR and OSR by 3mm.

I wonder if lowering causes even more preload on the antiroll bar? either non-neutral orientation of the bar or uneven loading side to side.

Similar threads:
https://f30.bimmerpost.com/forums/sh....php?t=1119748

specifically post 3:
https://f30.bimmerpost.com/forums/sh...08&postcount=3

My options are to either refit my original M Sport Springs to the rear (even though that still yield uneven height) or see if adjustable droplinks aid the issue.

did you see my post above? i figured one of the spring perches was incorrectly installed. before you start replacing parts, just jack up the car and take a look at orientation of the rubber perches.

[Matthewricha]

Originally Posted by designatedposter

did you see my post above? i figured one of the spring perches was incorrectly installed. before you start replacing parts, just jack up the car and take a look at orientation of the rubber perches.

Yes I did, many thanks for replying. I have looked before and all seems ok as far as I can tell. Agree they are not symmetrical with the other side. Have had car inspected by several garages. Perhaps I'll take another look.

Here is OSR (UK drivers side):



Here is NSR:



I do wonder what the significance of the dot or whole is in the spring perch cup that houses the upper spring pad.

Anyhow if it's wrong I won't be happy with my indy.

[XutvJet]

Springs are what set ride height. It would be very difficult to install rear springs incorrectly on these cars to the point that it causes a wheel gap issue. The rubber cups fit one way and it's obvious how they fit on the spring and in the cups.

I can't think of a single car I've ever owned that has had equal wheel gaps on opposing sides of the same axle. Most cars have a difference of around 1/4" and even up to 1/2" on cheaper makes. Every car forum has reports of this.

BMW doesn't make the driver's side rear spring taller to compensate for the driver. The reason we know this is there is no parts number difference. We also know that people report varying gap heights on OEM springs. Sometimes the driver side is shorter, sometimes the passenger side.

As I said earlier, the issue is manufacturing the tolerances of coil springs. You simply can't make a spring deliver perfect wheel gaps all around. It's a coiled and formed piece of steel.

[KennyFSU]

As mentioned, I've also noticed this on almost every car I've owned, stock or full coilovers, they eventually go out of spec.

[jliuod]

I am not sure if this applies to BMWs. With the Miata suspension system one has to loosen ALL suspension related bolts and let the weight of the car rest on the ground before tightening. Another way to achieve this is to place the jack point on the bottom of the wheel hub and raise the whole car until it comes off the jack stand. Then, and only then you can tighten all the bolts. If that is not done binding will occur at the bushings thus eventually causing premature wear. Also, the ride height will be affected.

[aerobod]

Originally Posted by jliuod

I am not sure if this applies to BMWs. With the Miata suspension system one has to loosen ALL suspension related bolts and let the weight of the car rest on the ground before tightening. Another way to achieve this is to place the jack point on the bottom of the wheel hub and raise the whole car until it comes off the jack stand. Then, and only then you can tighten all the bolts. If that is not done binding will occur at the bushings thus eventually causing premature wear. Also, the ride height will be affected.

This is the same procedure that BMW specifies when any suspension work is carried out to ensure bushings are clamped in the normal ride height position. It is also advisable to release any residual tension caused by the tyres scrubbing when the car is lowered, before tightening, either by rolling the car backwards and forwards or putting a low friction pad under the wheels on one side of the car (plastic bags under the tyres can do this).

[Matthewricha]

Agreed... although I don't think height difference is spring tolerances as people have swapped springs side to side and ended up with the same result. Could be worn rubber spring perches or more likely the metal chassis where the spring cup mets the chassis is slightly lower on the NSR. I also think worn of saggy Subframe bushes can cause differences.

I'm 99% sure the springs are installed correctly. The height difference was there even with the original springs. I'm reasonably happy with the height difference. What I'm not happy with is the handling on the NSR which seems to have worsened with the fitment of the M Performance springs. I believe the Antiroll bar is preloaded as standard to allow for LHD (that's what the common belief is) so that when a person sits in the car the preloading disappears(?) ..and that lowering further causes the suspension geometry to change.. I could be wrong.

[aerobod]

I would check for damage due to pot hole impact that can exhibit itself in a few ways, if it hasn't already been done:

- strut tower "coning", where the top of the strut tower is no longer flat (the opposite front corner could be causing a ride height difference in the rear)
- bent suspension arms (also possible if the car has been incorrectly tied down by the suspension when being transported)
- bent upright, usually evident due to higher camber on affected wheel.

[dradernh]

Originally Posted by aerobod

I would check for damage due to pot hole impact that can exhibit itself in a few ways, if it hasn't already been done:

- strut tower "coning", where the top of the strut tower is no longer flat (the opposite front corner could be causing a ride height difference in the rear)
- bent suspension arms (also possible if the car has been incorrectly tied down by the suspension when being transported)
- bent upright, usually evident due to higher camber on affected wheel.

Thanks. This is food for thought as I embark upon determining why my car is 3/4" low in the left rear.

[aerobod]

The other thing to ensure before doing any suspension measurements, although I am probably stating the obvious, is to do it on a known flat and level surface. I use a long straight edge and a spirit level to put tape marks on my garage floor where the wheels will rest and place shims in one or two of the wheel positions to give me a true level surface within 1mm or so.

[morphomeman]

I have an imbalance between the nuts on left and right. That seems to be fairly common.

[Matthewricha]

Originally Posted by morphomeman

I have an imbalance between the nuts on left and right. That seems to be fairly common.