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Massive steering wheel shuddering under high speed braking

PostPosted: Sun Aug 09, 2009 11:11 am
by toadcat
Hey all
The road to West Head just got re-paved so I've been *testing* it recently. However when braking from a high speed I get massive steering wheel shuddder...
I am only on stock Gen 3 NA brakes :| I m assuming its the rotors? Would upgrading to a set of B4 rotors/calipers do anything to solve this or should I get DBA4000's? Also, the pads on the car cook very easily... again - will I need to change the caliper to one with a greater surface area (ie B4 brakes) or will just a change from a economy pad to a street/track pad be fine?

Re: Massive steering wheel shuddering under high speed braking

PostPosted: Sun Aug 09, 2009 2:12 pm
by teK--
Def your rotors which are suffering from thickness variation. How many Kms on the car? They are probably due anyway (I never condone machining rotors as it has a high return rate once they get TV soon after).

My best bet is to upgrade to DBA 4000s slotted and some up spec'ed pads such as Bendix Heavy Duty (spirited everyday driving), or EBC Greenstuff (occasional track stint), or Hawk HPS (somewhere inbetween).

Re: Massive steering wheel shuddering under high speed braking

PostPosted: Sun Aug 09, 2009 5:54 pm
by todda189
Rotors !! i had the same problem in my gen III outback and we get cars come into work all the time with shuddering brakes ,we either get them machined or get new ones depending on what the customer wants done!!

Re: Massive steering wheel shuddering under high speed braking

PostPosted: Wed Aug 12, 2009 8:27 pm
by toadcat
The car has done 170,000 so I'd say it'd be them..
How much are OEM Subaru brake rotors+pads compared to DBA4000 slotted rotors and Greenstuff's? I had bendix ones before but didn't like them. Overheat quickly and spray brake dust everywhere... after a week the insides of my wheels were coated.

Re: Massive steering wheel shuddering under high speed braking

PostPosted: Wed Aug 12, 2009 8:47 pm
by Fangin_RX
My Brakes are like that, Clean the car and after a run to the shops its already turning black. Plus i have touched the brakes or rotors yet so but i do get the occasional squeal from the brakes which does annoy me quite alot after the brakes have had time to 'warm up' they become very loud and squeeky (Reckon its time for new pads?

Machining discs wouldnt be a problem for me as i do most of the discs where i work and none of them have come back complaining (Well not yet lmao)

Re: Massive steering wheel shuddering under high speed braking

PostPosted: Wed Aug 12, 2009 10:36 pm
by smythie
toadcat wrote:The car has done 170,000 so I'd say it'd be them..
How much are OEM Subaru brake rotors+pads compared to DBA4000 slotted rotors and Greenstuff's? I had bendix ones before but didn't like them. Overheat quickly and spray brake dust everywhere... after a week the insides of my wheels were coated.

The OEM stuff will be expensive. A lot of people rubbish them performance wise, but that criticism really only becomes relevant as you start pushing the brakes seriously hard. FWIW I have DBA4000 and Hawk Ceramics on the front of the 3RB and standard gear on the back (until it wears out when I'll probably go something aftermarket to match the front). They work fine once the pads get warm. Not particularly dusty but a little lacking in initial bite (particularly when cold). If you don't drive anything else, you'll get used to it well enough. I haven't exceeded the performance potential of that setup

Re: Massive steering wheel shuddering under high speed braking

PostPosted: Thu Aug 13, 2009 4:03 pm
by toadcat
smythie wrote:
toadcat wrote:The car has done 170,000 so I'd say it'd be them..
How much are OEM Subaru brake rotors+pads compared to DBA4000 slotted rotors and Greenstuff's? I had bendix ones before but didn't like them. Overheat quickly and spray brake dust everywhere... after a week the insides of my wheels were coated.

The OEM stuff will be expensive. A lot of people rubbish them performance wise, but that criticism really only becomes relevant as you start pushing the brakes seriously hard. FWIW I have DBA4000 and Hawk Ceramics on the front of the 3RB and standard gear on the back (until it wears out when I'll probably go something aftermarket to match the front). They work fine once the pads get warm. Not particularly dusty but a little lacking in initial bite (particularly when cold). If you don't drive anything else, you'll get used to it well enough. I haven't exceeded the performance potential of that setup

Sweet, thanks.
How much extra would the aftermarket gear be? I think I drive too aggressively in national parks for the OEM stuff - after about 5 minutes I can smell the brake pads - not nice :shock:

Re: Massive steering wheel shuddering under high speed braking

PostPosted: Thu Aug 13, 2009 4:10 pm
by GTSPECB STI
Subaru oem pads and rotors are farking rediculously priced for what they are. Shop around and do some price checks I suggest. I did Dixcel pad and rotor upgrades and paid less than half the price that Subaru wanted for their oem parts. Prospeed Racing FTW

Re: Massive steering wheel shuddering under high speed braking

PostPosted: Thu Aug 13, 2009 5:16 pm
by teK--
^^ What sort of price did you pay?

Looking at Prospeed's site, the 2pot or 4pot Dixcel SD slotted discs are $450.00 a pair. I doubt that the OEM ones are over $900.00 pair???

From memory DBA 4000s are only round $200.00 each.

Also are you running the Dixcel Type Ms or the Acre Super Fighters?

Re: Massive steering wheel shuddering under high speed braking

PostPosted: Thu Aug 13, 2009 5:46 pm
by GTSPECB STI
teK-- wrote:^^ What sort of price did you pay?

Looking at Prospeed's site, the 2pot or 4pot Dixcel SD slotted discs are $450.00 a pair. I doubt that the OEM ones are over $900.00 pair???

From memory DBA 4000s are only round $200.00 each.

Also are you running the Dixcel Type Ms or the Acre Super Fighters?


Now I can tell you I do have brembos on mine but two subaru dealerships quoted me the identical price on $1164 for front rotors and $544 for front pads. Call them yourself and see what they say.

I am running Dixcel type m's on the fronts and ACRE Super Fighters on the rears.

Re: Massive steering wheel shuddering under high speed braking

PostPosted: Fri Aug 14, 2009 6:49 pm
by toadcat
Just called them and got quoted a similar price to that.. Told them to go get stuffed... $1500 for the stock brakes? You'd have to be kidding.. Probably going to just buy a second hand pair of B4 brakes and upgrade the rotors to DBA4000s.

Re: Massive steering wheel shuddering under high speed braking

PostPosted: Fri Aug 14, 2009 10:11 pm
by teK--
GTSPECB STI wrote:
teK-- wrote:^^ What sort of price did you pay?

Looking at Prospeed's site, the 2pot or 4pot Dixcel SD slotted discs are $450.00 a pair. I doubt that the OEM ones are over $900.00 pair???

From memory DBA 4000s are only round $200.00 each.

Also are you running the Dixcel Type Ms or the Acre Super Fighters?


Now I can tell you I do have brembos on mine but two subaru dealerships quoted me the identical price on $1164 for front rotors and $544 for front pads. Call them yourself and see what they say.

I am running Dixcel type m's on the fronts and ACRE Super Fighters on the rears.


Oh I see :). What kind of dusting you getting with the Super Fighters? When it comes times for my brakes I will likely go DBA4000s and the SFs; the Dixcel combo is a bit rich for me!

Re: Massive steering wheel shuddering under high speed braking

PostPosted: Wed Aug 19, 2009 4:55 pm
by tehx
I just got the DBA 4000's and red-stuff pads. Massive difference particularly during high speed braking. The stock brakes on my Lib had some nasty fade and shudder. A test (on a private road) just out of Canberra from, 180km to 0, resulted in me getting down to only 100km/hr before the factory brakes cooked and became useless. Machining them only results in the same thing on your next decent brake.

You are looking at about 2hrs to install, $250 for fronts and a little less for rear's. Pad's around the same price. Also get your brake fluid flushed and have some decent fluid filled. I have used the green pads before but prefer the reds as the greens do fade quicker.

If you go brembo's make sure that your rims will fit around the calliper. More often than not you will need new rims to fit them. Personally the huge cost of the brembos & the ongoing costs of rotors and pads are just not worth it - the will keep you broke. DBA's and good pads offer much better value for money (initially and ongoing) and almost equal performance on the road. Bremob's are an overkill on the road but for race/track work, where you do lots of repeated & high speed braking, they shine. I'm yet to test the DBA's on a track but from asking around, people who have used them say they are very good.

I also took the opportunity to completely remove the callipers and paint them red. They turned out looking very sweet! I'm very picky when it comes to painting factory callipers as they stand out and little callipers look crap painted. The Lib GT's are huge on the front and look great, rears also came up really well. I have the 18 spoke rims so they are covered quite a bit - if you have rims that expose the callipers its worth visualising what they would look like painted.

Re: Massive steering wheel shuddering under high speed braking

PostPosted: Wed Aug 19, 2009 7:34 pm
by teK--
^^ Agreed. On public roads even driving at over the speed limit the Brembos will never be used to their full capability because you just can't replicate gruelling track conditions on public roads safely.

I am not sure of the rotor diameter for the Brembos, but the only advantage that 4 pistons has over 2 pistons (given the same rotor/pad size), is that there is better pedal feel and fade resistance. That is all.

IMHO for spirited road use DBA4000s and some good pads that are in the correct heat range for the type of driving that is intended are more than adequate for the non-Brembo setups.

The Super Dot 4 fluids used by most good workshops aren't actually too bad at all for street driving; they have a good service life of 18-24months and don't cost much. I have happily used Motul Dot 5.1 before which gives just that little bit more heat resistance but it is much more hydroscopic so 12 months is pushing it before having to change it out.

Re: Massive steering wheel shuddering under high speed braking

PostPosted: Thu Oct 22, 2009 9:53 pm
by smythie
Couldn't be bothered starting a new thread. Thought I'd provide some feedback to anyone interested in the DBA4000 and Hawk Ceramic combination on the front. The fluid was also flushed with Dot 5.1 at the start of the year (it's probably due for another flush when it gets home after the thrashing it has received the past week)

The brakes on my car have been pushed harder than ever the last week and in short they have been nothing short of confidence inspiring. I have hustled it up and down mountain (well what pass for mountains in this flat island) passes a number of times at just short of max attack and can say that overheating was never a problem, fading was never a problem, pedal feel was never a problem and overall braking performance was never a problem. I had the confidence to go hard for hours without worries of the brakes giving up.

This setup I reckon is easily more than suitable for any usage on the road and provides great braking performance.