Common Front end issues

[TOMatBMR]

What are common weak links in the front end? My 2006 M45 Sport has about 96k miles on it now and it has a slight tapping or knocking noises over small bumps in the front end almost like a worn our strut mount or sway bar link. Also, if going roughly 15-20 mph or while backing up if you tap on and off the brakes pretty hard you can feel like the front wheel has movement forward or back like the control arms bushings are blown out.

I have lifted the car up numerous times and can not find play anywhere in the front suspension components. I get wholesale discounts on wheels/tires/suspension through work and I am ready to start making modifications to the car but want to fix any issues before I put the money into aftermarket stuff. Unless of course there are aftermarket upgrades for any of the parts that need replacing.

Does anyone know what front end parts are common to wear on these? Is there a special procedure for checking for play in the front? I brought it 2 shops when I first bought it because I thought maybe I was missing something or maybe not inspecting it properly since its hard to shake it all down and inspect it at the same time. One told me there was nothing wrong with it and another said it needed control arms. I checked all the control arms and the bushings look fine.

Thanks for your help!

[AZhitman]

The bushings can look fine, and can resist "play" when manually moving it - Doesn't mean a thing. We're pretty puny when compared to the forces a 2-ton car places on its components. Won't really replicate it with your hands.

The old-school 'tests' (like bouncing the car to test shocks) don't really translate well to modern cars.

With that said, at 96k miles, she's past-due for shocks / struts. Lower control arm bushings are a common wear item that cause similar noises, and they're past-due as well. (Your "reversing/braking" test confirms that)

Also, I have seen a couple with some ancillary noises - One had an evap canister near the fuel tank that was loose and clunked over bumps, and another had some plastic shields on the rear shocks that seemed to rattle.

Regardless, you're on the right track with getting the suspension refreshed before mods - If that car was in my driveway, I'd order 4 shocks, new LCA bushings & ball joints (or the whole LCA preassembled), F&R sway bar bushings and end links, and get her back to as-new condition.

[TOMatBMR]

Yeah I'm thinking I'm going to start with all new struts, shocks, mounts, lowering springs and sway bar links. I just installed some Bilsteins and H Techs in a friends IS300 recently and LOVED the way it drove it after but it appears KYB may be the only option for the M.

The car has 20x8.5 forged wheels on it now that are in poor shape so I am doing Niche Milan 20x10 +40 all around with the 245/35/20 tires that are on it already.

Photo of the car when I picked it up a few months back:


I hadn't found any places or upgrades to rebuild the existing control arms. Are you aware of any?

Thanks for the reply.

[Ilya]

Honestly, you have a good game plan. But if it was me, I wouldn't bother with struts/shocks + springs. You're going to spend around $700 for those parts most likely, so why not just spend $900 or so and get legitimate BC Racing (not-true coilover) or D2 coilovers (true coilover)?

So, if I was you, I'd do what AZ said:

• Coilovers
• Mounts
• Sway Bar Links front and back
• Sway Bar Bushings front and back
• etc.

[TOMatBMR]

The bushings can look fine, and can resist "play" when manually moving it - Doesn't mean a thing. We're pretty puny when compared to the forces a 2-ton car places on its components. Won't really replicate it with your hands.

The old-school 'tests' (like bouncing the car to test shocks) don't really translate well to modern cars.

With that said, at 96k miles, she's past-due for shocks / struts. Lower control arm bushings are a common wear item that cause similar noises, and they're past-due as well. (Your "reversing/braking" test confirms that)

Also, I have seen a couple with some ancillary noises - One had an evap canister near the fuel tank that was loose and clunked over bumps, and another had some plastic shields on the rear shocks that seemed to rattle.

Regardless, you're on the right track with getting the suspension refreshed before mods - If that car was in my driveway, I'd order 4 shocks, new LCA bushings & ball joints (or the whole LCA preassembled), F&R sway bar bushings and end links, and get her back to as-new condition.

I also just realized you are local to me, I live in Phoenix and our shop is in Phoenix too. Do you attend any local meets or events often?

[TOMatBMR]

Honestly, you have a good game plan. But if it was me, I wouldn't bother with struts/shocks + springs. You're going to spend around $700 for those parts most likely, so why not just spend $900 or so and get legitimate BC Racing (not-true coilover) or D2 coilovers (true coilover)?

So, if I was you, I'd do what AZ said:

• Coilovers
• Mounts
• Sway Bar Links front and back
• Sway Bar Bushings front and back
• etc.

I checked for coilover options through my wholesale connections at work and we don't have access to either of the those brands so I was trying to stick with what I can get at wholesale. I will have to give BC or D2 a call and see what their wholesale requirements are and see if I can get an account with them.