So, I know I am exposing he soft underbelly of my mechanical knowledge here, but can anyone tell me what exactly tie rods are and what do they do? Just got my 04 Cooper S back from the 40K(ish) service and one of the items listed on the service sheet stated that both front tie rods were "siezed" and that they had been replaced under warranty. What kind of driving/abuse would cause this "seizure" and is this a known weak point on our cars?

 

Here you go. I have not heard of this before. Is your suspension modified?

 

Nope, car is completely stock. Spent the first 3 years of its life on ridiculously bumpy Eastern UK roads though.

 

I just had to have the control arm bushings replaced at 44K miles on my 2002 MCS...ost of the mileage accumulated on the ridiculously bumpy Washington DC area roads.

The really bad news was that the subframe itself was bent and had to be replaced too (I saw the damage and approved replacement before they did the deed.) The part cost alone for the subframe was like $800.

Between the lines, and also if you read about all the front strut tower mushrooming problems people have had it seem that the front end is not really designed for use in rough urban streets. My problems were with 16" non runflat tires, too. I can't imagine how much abuse 17" runflats would do to the suspension over time.

 

You're not kidding. I was running the 17" Goodyear Eagle All-Season RSAs until recently. The tire lacked grip, was extremely harsh over bumps, and my left rear started making a grinding noise that you'd swear was coming from the drivetrain. I just switched to the Pirelli Eufori runflats, and while still a bit harsh, they are a HUGE improvement over the Goodyears. Much better, quieter ride. The best part: they cost almost $100 LESS !!!! than the Goodyears. Hopefully the extra compliance will also pay dividends on my suspension in the long run.