Why do my brake discs only last 3 months?

Oct 2012: Vehicle purchased from car supermarket. During the preparation process they had replaced the brake pads. Suspect non LR parts.
July 2013: Front brake discs replaced by main dealer due to warping. Pads not replaced as barely worn.
Oct 2013: Front brake discs replaced again, under LR parts warranty, due to warping. I requested the pads were replaced at the same time but they weren't as they were barely worn.
Now: Discs are warped again.

The warping is evident when braking, the steering wheel vibrates. Nothing else has been found wrong with the vehicle. It also had 2 new front suspension arms in July 2013 (if that's relevant?!)

Guidance needed please. I'll get the discs and pads replaced again but is there something other than the pads that could be causing the warping? The car drives absolutely fine each time new discs are fitted.

My guess - the non-LR pads are overheating causing the discs to warp. I wouldn't entertain a new set of discs unless the pads are replaced at the same time. even if at your cost. FL2 2007 57 GS
D2 2005 Td5 - gone and not missed
FL1 2005 Td4 - gone and missed

Hard to say without looking at it. Do both discs warp or just one? My first port of call would be to check that the callipers are sliding properly because if either one is sticking you end up with uneven pressure on each side of the disc which after a while will "bend" it. The fact that they are OK when just done tends to rule out bent hubs or poor fitting. John
07 HSE Narvick Black
Land Rover Series One
Triumph Rocket 111 (sadly gone!)

Thank you for replies. In October, I specifically asked for the pads to be done as well, knowing that would be at my cost. However, I used a local dealer rather than my preferred dealer and they basically threw the keys back at me and said they'd replaced the discs. I was annoyed that they'd not replaced the pads but pleased that the car was fixed and hadn't cost me anything.

I've emailed my preferred dealer (Farnell Bradford) to book it in for new discs and pads.

I thought it was a golden rule that new disks always required new pads to prevent disk damage due to uneven pressure from worn pads that have attained the profile of the old worn disk. Jules

Would agree with Jules ref new pads when changing discs.

Would stick to OEM parts as well. On previous cars (LR or other makes) have had problems with bedding in and long term life - but correct fitment is important. Making sure the callipers are free of crud and corrosion takes time and makes sure that the new pads can move correctly and bed in well. OEM parts can be found from various sources and some are available as a pack of discs and pads together on ebay. 2016 BMW X3 30d SE in red
MY2013 SD4 XS Firenze Red, 19" 10 spoke contrast paint wheels, Signature Strips, Grand Black Lacquer trim, Cold Climate Pack - gone!
2007 TD4 S Stornoway Grey - gone!

Update: After 2 lots of warped discs, LR dealer replaced the pads. Old ones were not genuine so suspected to be the cause, overheating and warping the discs. Discs replaced twice under parts warranty, I only had to pay for the pads. Great service!

It has been said that the quickest way to ruin a set of Discs and Pads, is after prolonged use of the brakes, sitting with your foot on the brake, all the heat is then in one place.

When servicing brakes its of key importance to check each part as you go along. warped discs is rarely a disc problem, it is other seizing / stiffness that cause overheating.
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Might I suggest the following.
1/.'lever the old pads clear of the disc and get an assistant to press the brake pedal as you watch the pistons reclaim the gap; repeat and look for a lethargic or sticking piston.
2/.remove the pads then (if fitted) remove the stainless steel slider guides, clear any corrosion from the groove in the carrier before applying a smear of copper grease and replacing the stainless slider guide. if no s/s slider then still clean and grease the groove.
3/.check the carrier slides easily on its stainless pins, its usually never a problem these days.
4/.check fit the new pads, they should be a light rattle fit where the 'ears' or 'lugs' fit into the sliders. if they are at all tight its wrong and you will have to file the burrs off the steel pressing until all moves without sticking. Smear the 'ears' with coppergrease when final fitting.
5/.check the disc for any patchy corrosion; this is indicative of a car standing unused for a few weeks. ive done many write off cars over the years and if you don't clear off the surface rust it just glazes over leaving a high spot and causing brake judder.
6/it wise to bleed the brakes thoroughly at this point to get clear clean brake fluid through as a purging flush through, start at the back first.
7/. use gentle braking for the first say 100 miles whilst all 'beds in'.
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If you are not competent to do the job yourself then at least you will be a bit wiser when discussing with you garage whilst the job is done.
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Hope this helps, kind regards from Fred
. 2010GS Auto ex Celeb, Santorini Black, 2011 facelift , spoiler, spats, mudflaps, LED footwell lamps, Witter detach,
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1958 & 1959 Austin J40 Pedal Cars under restoration (I make many J40 parts)
If you have an Austin J40 or Pathfinder Pedal Car looking for a new home pls PM me.
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