Annoying noise when going over small bumps at low speed

[tony168]

Dear All - Happy New Year all ....its been great reading all your postings..!!

I have a annoying problem with my Mini which I haven't been able to solve for some time now. When going over speed bumps and driving at very low speeds ie 10-25km on a bumpy road, I can hear a 'clunk' noise coming somewhere from the front wheel. From this, I feel a small impact on the steering wheel. At high speeds, I don't have this issue. Im not sure if this is a common issue with my 2002 Mini Cooper Automatic which doesnt need fixing but it's really annoying. As my wife drives the car with our kid in the back, I'm also worried its something dangerous. I've even taken the car to various garages to have it fixed and they still cannot see where the problem is coming from. They have tested the suspension, checked if the wheels are loose. Not sure if the problem is related to the common problems relating to the power steering. Has anyone experienced this problem before? Thanks in advance for your responses.

[C.Noble]

How many miles has the car done?

There are several things that can cause what you are describing, but any half decent garage should be able to find them within ten minutes.

My first check would be the lower or inner ball joints, track rod ends or steering rod "drumsticks" (the ball and socket joint at the steering rack end of the track rod).

These can easily be checked by jacking up the front wheels so they are clear of the ground and grabbing the wheels with your hands at 12 oclock and 6 oclock and see if you can get any play, if you feel any clicking/clunking, it is most likely the lower ball joints or inner ball joints.

Do the same test again, but with your hands at 3 and 9 oclock, if you feel more play on one side of the car than the other, then it is likely to be worn track rod ends or "drumsticks".

If you feel no slack in any of these areas, my next suggestion would be the wishbone bushes, these are known to wear out at around 40,000 miles (although I do know of them wearing out faster, depends on use, driving style, tyre size, etc, etc)

The bushes are a little more tricky to check, as they need to be checked with the weight on them, and, unless your mini-me, it is only possible on a four post ramp or a pit. As a guide tho, on the race cars I look after, we religiously change these bushes at least twice a season (a bit excessive for a road car I know!) but our way of checking is when we torque the wheel nuts with the hand brake on, if the front wheel moves forward or backward more than 13mm (1/2 inch) within the wheel arch, we replace the bushes.

hope this helps.

[tony168]

Thx Spannerman. Your response and help is greatly appreciated. My Mini has done approx 54k km.

I will take your suggestion to the garage sometime next week and see if my problems are coming from any of the above. I hope so as I really want to find out where the problem is coming from.

Thanks again

[robotchr]

However, the noise mitigates after the tires have warmed up so I'm thinking it's the run flats. Once they warm up the thumping all but disappears. I bought Continentals to replace the Goodyears, hoping it would solve the problem. No luck. Perhaps the tires need to be remounted and rebalanced?