Hi,

A. If front brake discs are lipped/ scored is that the most obvious reason for juddering under braking (newly fitted tyres made no difference)?

B. Brake pads are only 30% worn so if fitting new brake discs is it essential to fit new pads?

Thanks

No idea if its necessary but I would The forums premier drug dealer and human trafficking consultant


Range Rover Vogue SE 4.4 TDV8, Range Rover Sport HSE 3.6TDV8, Audi S8 V10, Jaguar XKR Conv, Jaguar XJS V12 Conv, Land Rover Disco 3, Lexus LS 400 MkIV, Lexus LS400 Mk III.

Yes I would, solely because you dont know if the pads are worn in different places, plus if its stripped down already, for the extra cost you may as well do it.

You need another category:
"May not be essential but would anyway."
 John
2008 Stornoway Grey 3.6 Tdv8 Vogue
2005 TD6 Java Black Vogue - Written off!!
GAP iiD BT
2003 Discovery TD5 Auto, Nanocom Evolution - gone to a new home!
MasseyFerguson 152 - No electronics!! - Sold

I've always thought this to be essential. The pads will be worn to the profile of the previous disc. Therefore they won't make full contact with a new disc and depending on how bad the profile of the old disc was this may well take a long time, during which you have an impaired braking system.

Given all the labour is going to be done anyway, why on earth wouldn't you?

MW Car history includes: LR Series 3, RR Classic x 4, LR 101, Discovery 1 and 2 and now FFRR.
Yes I'm a masochist....

Essential. Pads wear to the disc, new disc new profile and reduced friction material = potential loss of brakes.

Well, I might get slated for this but I have re-fitted used pads with new discs but I did take a moment to ensure they were flat using a very coarse file. This was only due to the fact it was a Sunday, I couldn't get new pads as they were out of stock and I had to do the job to replace a cracked disc.

Not entirely the best way of doing things but on balance it was better than driving with a cracked disc. Wasn't on a FFRR either, just my old work hack. Given the choice I always fit new pads.

The comments about non-matching profiles though, well that is what you get with new pads and used discs. In this scenario there is a longer bed-in time than when replacing the lot and this is something we have all done for many years. It's very pronounced on sliding calipers as well. The pads in my Skoda always wear in a taper so the discs actually get more wear on the innermost part where the caliper exerts most force. With new pads, a few miles of gentle braking soon sorts that out.

in an ideal world i would fit new pads with new discs , but at £200 for pads i would try the slightly worn pads and use Dom's method of lightly cleaning the pads up with a file... ... - .- -.




Y. O. L. O.
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Clivefog wrote:

Essential. Pads wear to the disc, new disc new profile and reduced friction material = potential loss of brakes.

mzplcg wrote:

Well, I might get slated for this but I have re-fitted used pads with new discs but I did take a moment to ensure they were flat using a very coarse file. This was only due to the fact it was a Sunday, I couldn't get new pads as they were out of stock and I had to do the job to replace a cracked disc.

How could you ???...its 40 lashes for you  The forums premier drug dealer and human trafficking consultant


Range Rover Vogue SE 4.4 TDV8, Range Rover Sport HSE 3.6TDV8, Audi S8 V10, Jaguar XKR Conv, Jaguar XJS V12 Conv, Land Rover Disco 3, Lexus LS 400 MkIV, Lexus LS400 Mk III.

40 nights of getting lashed eh Jim? Works for me

Not talking about our own RR by the way... I always would but was curious as to the technicality correct answer.

Surprised at how many replies so sooon but thanks

Ps... IMO... good counter observation about when fitting new pads with existing discs...

If the pads have plenty of life left, I flatten them and reuse them. The labour isn't an issue as I'm not paying anyone to do the job. Ron B. VK2OTC
2003 L322 V8 Auto
2007 Yamaha XJR1300
Previous: 1983, 1986 RRC; 1995, 1996 P38A; 1995 Disco1; 1984 V8 County 110; Series IIA

I usually find that the pads are gubbed by the time the disc needs replaced. Got - 2017 SDV8 Autobiography in Loire Blue
Had- 2008 TDV8 Vogue SE in Java black
Had - 2007 S/C in Stornoway Grey

Like most of the posts.. our trusted mechanic has since advised ALWAYS fit new pads if fitting new discs (despite the fact the pads in question have 70% life left...