Hey all,

My front brakes have been squealing like crazy when coming to a slow stop. I've already tried using anti-squeal compound. My Infiniti tech told me the OEM shims weren't on there. So I've called my local stealership and game 'em my VIN...they said there's not a shim kit for my G, and that no shims come with the OEM pads. Does this sound right? I was definitely surprised to hear this especially since so many on this forum have mentioned the shims...should I try another dealer?

Can you guys confirm the part number I need if these shims do indeed exist? Or can I get new shims by replacing my pads with another brand.

Currently I'm running Axxis Ultimates on my StopTech AeroRotors.

TIA,
B

 

The OEM FRONT Brembo pads come with shims already attached, so there is no separate part number for the shims. You'll have to get some made. The REAR OEM Brembo pads do have a separate shim kit, however.

 

Thanks man, appreciate your help. Looks like I may need to get an aftermarket set. Anyone know of a good aftermarket front pad set for the Brembos which has a shim kit built in?

 

Quick question - I see lots of G35ers saying to keep your OEM shims when changing brake pads. So I guess that means they detach from the OEM pads, and can be re-used when going aftermarket. Is that accurate?

 

i think the axxis pads do. on second thought, it may be just on the rears. some great aftermarket shims are the stoptech's. they are made of titanium to minimize heat transfer from the pad to the piston.

 

OEM Shims are individually acoustic tuned to match a spedific pad noise signature...........Generic shims may help some when used with a non specific pad.

Important to match Durometer Nitrile elastomer of shim layers to vibration signature:
http://www.eaglepicher.com/NR/rdonly...RAKESFINAL.pdf

Something which appears so simple like a shim is actually a lot more complex than the pads it clips on to.

Wolverine is the master in this area and have 80% of worlds design and production.

 

So I wonder why my brakes sound horrible while other's are fine? Especially since StopTech sells these pads/rotors together? Anyway, what are my options? Just plug and play different shim kits until I find one that works? Would a Wolverine kit do me justice?

Thanks,
B

 

The engineering of an individual shim to a pad set probably takes a month and costs $50,000+ to begin production...........only adds a few dollars per vehicle + actual shim cost.

Luckily oem pads are usually the same shape year to year so only the material of shim must be tuned..................

Aftermarkets just buy a shim that will fit and hope it performs ok. Just like aftermarkets by generic pad mounting metal and apply their version of a compound and HOPE that what works on one car will work on another of similar weight......................no engineering very little if any testing just marketing and prayer.

Some are lucky [especially those that oem for BMW] since the products are in same weight and performance class.

Very little can be done without a computer file of the acoustic output of pad and rotor and how they are mounted..............wheels add complexity to sound.

http://www.bksv.com/default.asp?ID=3255

Important to have data on pads : 1st bending and 1st twisting mode frequency along with 2nd and 3rd harmonics see the following:
http://www.sae.org/events/bce/presen...2006matozo.pdf

You can use microphones, sound cards, and free software [21 days] to record squeel and analyse to determine what's going on just as oem does when analysing brakes pads, rotors, shims
http://www.sigview.com/

Hopefully you realize aftermarket companies don't do any of this scientific work!

Look at these Horiba multimillion dollar test machines and ask your pad supplier where theirs ar located [if they even know what you are talking about].

http://www.ats.horiba.com/giant7000series.html

 

Thanks for the info...so I guess I the short answer is I can try a shim but it's a shot in the dark.

 

It may be, but I haven't tried to remove the old shims, as I just went with new OEM pads. Though they dust a lot, the OEM's stop really well on the street. It looks like you probably can separate the shims from the OEM Brembo pads, but as Q45Tech pointed out, it's a bit of "hope and a prayer" as to how well they reduce squeal. I would think if you were to use enough brake lube, you could probably be fine, at least for a while.

Were I to track the car more and use more aggresive pads, I wouldn't care much about squeal under braking, and thus would leave off shims for the track.

 

Thanks...

 

did u completly cover the back of the pads with anti squeal and install them without rubbing it all off? ive been using hawk hps pads(which are known for squeals) for the past 7-8k miles with no shims on oem brembo rotors with not one squeal to date...... heres the product i used and covered the back of both pads quite a bit and then let them sit for 5-10 mins to become slightly tacky(followed directions on back of bottle)



http://www.crcind.com.au/catalogue.n...ElemFormat=jpg

 

Actually when we originally installed them I didn't use the anti-squeal compound. So I went back and had someone put in on there about a few months later. It didn't change anything though.

I did notice the rotors have some minor grooves in them. I've already contacted StopTech on how to fix/repair those grooves. I guess it's possible that's the reason for the squealing too....

Anyway, thanks for all the info - I'll keep you all posted.

-B

 

Rotor grooves are caused by hard spots in pads [nonhomogenous pad material] or tiny hard road rocks getting embedded into pads.

Failure to clean pads and do mainteance during pad life the most likely cause!

 

What kind of maintenance is required, other than checking to see if they are wearing down? I've had them in for less than a year (~15000 miles)...

And how do I fix the grooves?

Thanks,
B