A

aerofabrique

Active Member

• May 16, 2012

• #1

Dear Landyzone,

I have been a very good boy this year....

Would it please be possible to add a new sub section with common faults and problems in this RR section with specific items such as suspension, brakes, body and fittings, Diesel engine etc etc

This would make a single place for people to post about specific problems without the need for repeat threads and make it even easier to search?

I ask this because, while I give out loads of information from my own experience with brakes I am completely stumped with brake judder. Two new sets of discs and pads, non auto so no hot spots from holding the pedal down, new bearings, calipers, pistons and 2 new hubs assemblies. and still after about 1000 miles i get judder through the steering wheel. I've spoken to the well known brake company and they can't provide a specific answer but have had a lot of queries with the P38.

It seems a lot of others have this problem it would be nice to have a definitive thread/section on RR brakes?

Thanks - there's beer and pasties by the fire

Aero.

 

C

clarkie

Active Member

• May 16, 2012

• #2

have you tried swaping the wheels back to front just to rule out a tyre/balance problem?

 

Pikey

Dummy Ejection Facilitator..

• May 16, 2012

• #3

Just get the butler to sort it??

 

A

aerofabrique

Active Member

• May 16, 2012

• #4

clarkie said:

have you tried swaping the wheels back to front just to rule out a tyre/balance problem?

Click to expand...

Yeah all tyres balanced twice! as i noticed it'd thrown a weight the last time.

Laser Alignment all done at LR indie
Brakes bedded in properly at each change as per instructions
EBC ultimax compound
Very clean (new hub/disc) mating faces
No spotting
No glazing
Correct Wheel nut torques
New Shocks

The tyre on the NSF has outer shoulder burn but was told this was normal due to the nature of "the roundabout" in the UK. However even with the normal rotation of tyres I do every now and again it makes next to no difference.

EBC are great with their support but can't provide the answer. They say many RR owners come to them after fitting discs and pads an the judder reappears.

 

zzr1200

Well-Known Member

• May 16, 2012

• #5

What tyres are fitted to your range, make/size???

 

A

aerofabrique

Active Member

• May 16, 2012

• #6

zzr1200 said:

What tyres are fitted to your range, make/size???

Click to expand...

good point... L322 18" with spigots 265/60 r18 or something like that. L322 18 inch correct size anyway - slightly larger than P38. However can't see how these would have such an adverse effect on braking but maybe it does. They were never built for these wheels...

 

jt_armstrong

Well-Known Member

• May 16, 2012

• #7

I'm assuming that when you replaced the discs that the judder goes away for a period of time. This pretty much rules out the impact of wheels and tyres. I had a similar event on my '97 which developed brake judder 2000miles after new discs. I built a simple jig that allowed me to check if the disc was warped which they were - no option other than to buy new discs. I did notice that I had incorrectly fitted the pads. I failed to spot that the pads I fitted had a chamfer on one edge of the braking material. As luck would have it, I had all 4 pads fitted back to front. The replacement pads had the chamfer on both edges. Not sure if this would have caused the warping but since the new discs the judder has not returned.

 

S

stopover

Active Member

• May 16, 2012

• #8

Are you confusing brake judder with the vibration you get when the ABS kicks in. If the brakes need bleeding then you can get a softish pedal and a vibration from the ABS trying to handle the situation.
If you do bleed the brakes then study the workshop manual as its no good just bleeding a nipple. Its quite involved and worth doing both high and low pressure systems anyway. After a 1000 miles the brake pads would have bedded in and could lower the brake fluid level, maybee at some point too far. The level should be correct with engine running.

 

Last edited: May 16, 2012

A

aerofabrique

Active Member

• May 16, 2012

• #9

stopover said:

Are you confusing brake judder with the vibration you get when the ABS kicks in. If the brakes need bleeding then you can get a softish pedal and a vibration from the ABS trying to handle the situation.

Click to expand...

Nah This is judder as in the lower facia fixing panel under the steering wheel falls off.

Most noticable from 60ish down. Slow progressive braking will initiate the judder and increasing the pressure gently will snowball the effect until it feels like a wheel is about to fall off - release and it goes, press again and it back but not as visciously.

Slam it on from 60 does what its supposed to do, ABS in and no judder. Deffo not ABS and pretty sure it's DTV. However it's this that I cant work out how it's being caused.

Brembo Discs with EBC ultimax pads ( double chamfer so impossible to fit wrong - i hope!)

 

S

stopover

Active Member

• May 16, 2012

• #10

OK, as JT then it may be your disks are warped. Do you get the vibration when first starting off whilst the disks are relatevely cool. And at 60 + cold air cooling them more but holding the brakes on progressively then a lot of heat generated? Have you checked the run out and thickness of the disks?

Oversized tyres might prevent air cooling the disc?

Had an Aston Martin DBS V8 some years ago. When starting out all was ok for a while but after x miles and some hard braking I got a bad vibration. My disks had warped, had them skim'd - no good just worse shaking the car badly. Had to replace them, not cheep! Lovely car though wish I still had it.

Reason I mentioned ABS was because we had a 2001 Autobiography in with a brake judder problem. Drove OK but quite a bad vibe when braking, a complete bleed did the trick.

 

Last edited: May 16, 2012