In this brief article, we are going to discuss the different BMW Suspension problems, what the causes are, and their troubleshooting Tips.
What are the most common BMW Suspension issues?
The most common BMW Suspension issues are:
- Front Spring Breakage
- Rear Squeaking Noise
- Front Lower Control Arm Failure
- Front Strut Top Mount failure
- Front ‘Clunk’ Noise
- Rear Shock Absorber Failure
BMW types of suspension
Model years: 1992-2006 3-series, 2003-2008 Z4
Front MacPherson Strut with Boomerang Lower Arm
- E36 (except 318ti)
- 3-series, including M3 E85/E86
Rear Trailing Arm
Model years: 2006-current 1,2,3,4 & series
- E82 1-series
- F22 2-series
- E9X 3-series
- F30 3-series
- G20 3-series
- F32 4-series
- G22 4-series, including 1M/M2/M3/M4 models
- G29 Z4
Front MacPherson Strut with Twin Lower Control Arms
“3-link” rear suspension with semi-trailing arm, an upper link and a lower link
Front Spring Breakage
- Squeaky suspension
- Creaking and Popping noises while going over bumps
- Sudden drop in suspension height at a corner
- Issue mostly seen in the BMW 1 Series 8X
Troubleshooting Front Spring Breakage
- In a majority of cases, the spring fails due to the combined effects of corrosion & fatigue over a period of time.
- The service life of the spring depends on whether the car is used over roads that have salt or in an atmosphere where there is a lot of moisture. Failures usually happen closer to 100K miles.
- For replacing the Spring from a strut, you need to first compress the new Spring in a spring compressor. You can either use a hydraulic compressor (preferred) or a Threaded Bolt type as well.
Rear Squeaking Noise
- The Rear squeaking happens during normal driving
- Squeak is heard even on a smooth road
- Usually seen in 1 Series and 3 Series
Troubleshooting Rear Squeaking Noise
- In order to identify where exactly the squeak is coming from, you can simulate the rear suspension movement and closely observe the squeak closely
- For this, lift your rear body and place it on Jack-stands
- Now use a hydraulic jack to lift and lower the rear wheel hub to simulate suspension movement
- Move the rear wheel carrier up and down a few times and listen closely for the source of the squeak noise.
- If needed, you can use a long shaft Screwdriver and place the handle at your ear while the tip is at various suspension mounting points.
- Lower Control arms are known to squeak from past experience
- If the bushing is still intact and in working condition, you can try a “Quick-Fix” solution to eliminate the noise problem
- Use a Pointed tool to poke holes into the exposed Rubber Portion of the Bush
- Spray a long-lasting lubricant like WD 40 or Wurth ultra 2040 into the new bushing holes using a nozzle
- Once again, using the Hydraulic Jack, move the rear wheel carrier up and down in order to let the lubricant spread throughout the joint.
- Lower the vehicle and see if the problem has been eliminated in normal driving
Front Lower Control Arm Failure
- The car seems to be drifting; poor handling
- Steering seems vague while Lane Changing
- Uneven Tire Wear pattern
- Knocking Noises while going over Rough Patches
- Usually seen in BMW 1 Series E8X and 3 Series E30, E36
- Due to a Tire wear issue, it can be inferred that the alignment of the front suspension is not within the recommended settings. But this is still a symptom.
- The BMW E8x has 2 Lower control arms with a total of 2 bushings and 2 ball-joints. Apart from the Tie rod arm, these links largely influence the suspension alignment settings
- The root cause for out-of-alignment suspension points to the Lower control arm Bushings and Ball-joints that may have got worn out or damaged.
Troubleshooting Front Lower Control Arm Failure: Bushing
- Lower Control Arm bushing wears out over time and cracks due to age
- To assess the bushing condition, you can use a Pry-bar and insert it between the Lower control arm and the Subframe. Now, try to move the Lower Control arm using the Pry-bar and observe the movement at the Bush location. If the lower control arm moves without much force, then it means that the bushes have worn out.
- When inspecting the Lower control arm after removal, it is clear that there are tears and cracks in the rubber portion.
Troubleshooting Front Lower Control Arm Bushing Failure: Lower Control Arm Ball-Joint
- The lower control arm ball-joints are also subject to wear and tear.
- The deterioration is usually initiated as a crack or rupture in the rubber boot around the ball-joint
- This leads to loss of lubrication and finally to complete wear out
- The wear out causes play or movement accompanied by knocking noise. The play in the ball-joint is one of the reasons for the vehicle steering feeling value
- You can easily check for Ball-joint condition by this simple procedure:
- Get the car on a Ramp
- Lock the steering wheel
- Hold the front tire with both your hands and try to steer the wheel
- If you hear a ‘Knock’ or ‘Click’, then it is very much likely that the noise is due to a play in the Ball-joint
- The best course of action would be to replace the whole Lower control arm since it comes with 2 new bushings and 1 new ball-joint all pre-assembled
- For Rusted Bolt connections that are hard to Break-open, do not try repeatedly using hand or pneumatic tools.
- Always first soak it for 10-15 min after spraying a good Rust-penetrant
Front Strut Top Mount Failure
- When the car is at standstill or very slow speed, ‘Knocking’ or ‘Creaking’ sound every time the steering wheel is turned
- The noise increases when trying to lock the steering in parking
- Seen in 1 Series e8X and 3 series E30, E36, E46
Troubleshooting Front Strut Top Mount Failure
- The Top Strut Mount contains a Bushing as well as a bearing that allows the strut to rotate while steering
- Generally, when the Top Strut mount is damaged, both the bushing as well as the bearing fail and restricts the strut from rotation during steering.
- The bearing failure causes the knock and creak noises while locking the steering.
- The Bushing failure causes the Knocking and Popping noises driving over a rough patch.
- The Strut Top Mount is assembled along with the Front Shock Absorber Strut. So for removing this, you would need to disassemble the Front Strut.
- In the interest of safety, Always use a safe method to compress and Decompress the Spring while dismantling the front strut assembly.
- It is preferred to use a Hydraulic or Pneumatic Strut removal fixture
- If that isn’t available, then use a Lead-Screw Type of Spring Compressor
Front ‘Clunk’ Noise
- Almost a continuous “Clunking” noise during normal driving
- The noise gets really worse on a rough patch or uneven road
- A problem found across all BMW’s that have Anti-roll/ Stabilizer bars
Troubleshooting Front ‘Clunk’ Noise
- Front Clunk noises on a Rough patch is most indicative of Anti-Roll bar (ARB) linkage related issue
- Apart from cornering, the ARB’s work a lot while driving on a rough road since the wheels articulate in a roll motion
- Inspect the ARB assembly and check all linkages
- The first linkage to fail within the ARB assembly is the Drop Links
- The Rubber boot covering the ball-joint usually ruptures due to ageing and the ball-joint inside loses lubrication and eventually rusts or seizes
Rear Shock Absorber Failure
- Bouncy Rear suspension
- It feels as if the rear inside wheel is ‘flapping about’ during slightly fast cornering
- Over rough roads the rear wheel feels ‘Floaty’
- Usually happens with 1 Series E8X, and 3 Series E30, E36, E46
Troubleshooting Rear Shock Absorber Failure
- Judder problems usually point to a problem in lateral grip. Now this could be either the tires or the Rear Shocks.
- It seems that the inside wheel was not planted enough on the tarmac to get lateral grip
- If the Tire is ruled out then the only remaining Root Cause is the Rear Shock absorber. Weak/Leaking Shock Absorbers can cause lateral grip problems.
- Check the shocks for Ruptured mounts and oil leakage stains on the shock tube
- Even if there are no oil stains, the shock could have simply worn out over the miles. Typically the shocks would last around 40K miles depending on usage. It is recommended to replace at 50K miles, when you would most likely see deterioration in performance
- While replacing the shock, make sure to replace the rubber mounts and bump stops as well.
In this brief article, we have discussed the different BMW Suspension problems, what the causes are, and Troubleshooting Tips.