Oreste

Hi everyone,

I recently bought a 1994 e420, it’s a great car but I’m having a problem with the steering, it’s vibrating.

When I bought the car it had 18” AMG replica wheels on it, they where rubbing and the steering was vibrating even though I balanced the wheels a couple of times and changed the steering shock-absorber. I though it could be a problem related it the wheels so I managed to get the original wheels and put them on the car but the steering is still vibrating, I’ve also balanced these wheels twice and the problem persists. Any idea what could be causing the vibration?

I’ve also noticed that the car is about 5mm lower in front right hand side.

Your help is appreciated.

Thanks

ShanMan

95% sure it's your brake rotors. V-8 cars are tough on rotors, and the OEM rotors (and aftermarket ones too) will warp pretty quickly due to the heat generated by a heavy car and relatively small rotors.

Pop fresh one's on and I bet your vibration goes away. Better still, opt for a big-brake upgrade because with those 18" AMG replicas, you have room to run a larger rotor, caliper setup. Bigger brakes will build less heat and thus warp less.

Oreste

Good idea, I didn't think of that. But if I put bigger rotors will I need to modify the caliper mounting?

Thanks

ShanMan

No worries. Search out the solution that Chris Pham came up with....it is super sano and required only minimal mods. Basically it was a bolt in with a brake line adapter IIRC.

Oreste

I'm not too sure about putting the 18" wheels back on since they rub against the wheel arch. I will take a look at Chris Pham solution.

Thanks

ShanMan

oh yeah, you have lots to research when it comes to whell fitment, etc. It's worth it, but it's lots of work none the less. In the mean time, drop in some OEM replacement rotors and I bet your vibration vanishes.

ShanMan

oh yeah, you have lots to research when it comes to whell fitment, etc. It's worth it, but it's lots of work none the less. In the mean time, drop in some OEM replacement rotors and I bet your vibration vanishes.

CDP

The steering knuckle gets in the way and depending on what size calipers and how the brake line input is on the caliper, you might need to trim the steering knuckle slightly and/or run an adapter for the line.

Also, I had the same issue regarding the steering vibration and it turned out to be the alignment and warped rotors.

dan_c

Well my rotors are brand new, steering damper brand new, rebuilt calipers, new bushings allaround, springs an shoks too, balanced the wheels several times, also realigned the steering (twice for the same reason, nothing else), and I still get a vibration... and other random isues: the steering pulls left or right all of a sudden! not hard, but it's not ok!

since none of the above worked, I have two other possible reasons:

1- my servo is shot! now this can be fixed (and it will be this weekend!). I hear the pump in the morning, or when I have to manuvre in tight parking spaces, full turning left or right.

2- some might remember I had a crash last winter (just before Christmas), and this one might be harder to fix. I noticed my left shok is having some isues when turning the wheels left or right. the car was up an elevator when I saw this... maybe I have to do some more measuring, to see if my left shock mount was not afected by the crash...

I've met the second posibility before, when I bought a crashed w201... it was repainted, and "repaired" by our romanian standards. I had to do a full front body work, and it was a b!7ch, seeing that sourceing the parts is really hard around here.


best of luck to you Oreste, and hope you fix your car soon and easy.

Oreste

Thanks for the info. I hope I don't have to do too much to the car. I will let you guys know what happens.

Thanks

Oreste

I was thinking about the rotors and it appears to me that if the rotors are warped I should be feeling some movement in the brake pedal, which I'm not. Is this assumption correct?

Thanks,
Oreste

ShanMan

probably yes, but possible not-so-much. It depends on the nature of the warping. If it is side to side, then likely you would feel some pulsing through the pedal. If it's radial, then no, you may not feel it in the pedal, but the vibration may persist.

Sometimes, there are inherent inaccuracies (flaws) in the raw rotor casting that results in an imbalance that cannot be felt until the rotor has been worn thinner. The removal of material lightens the overall weight of the rotor. Because the imperfection is internal, and was dampened when the rotor weighed more, the vibration was much less. But, with material removed the imbalance is magnified and results in a vibration that you will never be able to fix, and only gets worse over time.

childofjuly

for e420/400e you can use the late model r129 (sl500/600) rotors and calipers. they will fit without any mods.. great upgrade that i'm thinking about doing myself.

Oreste

Good idea, thanks.