Mk Iv Brake Pads

[TrevCooke]

I should know better than to allow my son to use my LS. I allowed him to use it on Saturday and he returned it with "Oh it has got a break wear message coming up on it".

Now I have a problem with the OEM pads in that doing 500 miles a week commuting to work means that the front wheels are always black with pad dust. I know EBC do front pads for the LS at £60+. Are they better that the OEM pads?

I am also going to change the brake discs themselves as I get a judder and whilst I am at it I will finally replace the parking brake shoes, so quite a brake overhaul coming up in the very near future.

How do the pad wear sensors work on the LS? I have had cars where the sensor wire is embedded in the pad itself so replacing the pad automatically replaces the sensor. Is the LS like this or have I to purchase more parts?

Trevor

[chips229]

Hi,

I cant help with the brake sensors,my mk1 didnt have them.

I know what you mean though about the sensors being part of the pad.On another car i owned the sensor sort of plugged into the pad.

Theres normally a far amount of pad left when the low brake pad warning light comes on,myself id take a wheel off and have a check to see how much pad is left just to be on the safe side ;)

From what ive read about ebc pads you would be better off getting the disc to match as they produce more heat causing standard discs to warp easier.

Good Luck..

Chips..

[chris vince]

Hi Trev,

I cannot help you with your enquiry, only to add that:

My discs are past the minimum wear level (MK4 Car also) and I intend to replace them.

A while ago I also placed an enquiring post on this site to enlist the experiences of other owners who had replaced their discs and pads, to try to ascertain the best combination OE or pattern parts.

Sadly my post attracted no replies other than Chips to reassure me that later Lexus discs have a slower wear rate.

I will watch your responses with great interest, and like to urge any other owners who have changed their discs and/or pads to recount their experiences and recomendations as to what combinations work well and more importantly not so well.

Regards to all,

Chris Vince

PS

Washer reservoir level indicator repair still holding fast with no false alarms or leaks.

[davepruce]

When I replaced them (on my Mark II) last the wires were on the pads (same as others I've changed in the past). So far I have replaced all four sets of pads with whatever I got from Halfords once since having the car (5 years and 50k miles), and the Low Pad warning light came on briefly yesterday so I will check them at the weekend.

They dont make too much dust and they work fine - they have to, I tow a 1200kg caravan 20 odd weekends a year and have never had a problem.

Trev, still having no luck with the rams!! Hey - its warm weather - they work OK!!!!!!

[lutonmatt]

the sensor wire works when the pads are low it wears into the sensor and brakes the circuit and puts the light on so if it does not come with new wires just connect the two wires together

and is your 400 the one with the ele aerial stuck up as its the same as my one the other silver one driving around chatham i got one and now i keep seeing this one

matt

[steve2006]

I should know better than to allow my son to use my LS. I allowed him to use it on Saturday and he returned it with "Oh it has got a break wear message coming up on it".

Now I have a problem with the OEM pads in that doing 500 miles a week commuting to work means that the front wheels are always black with pad dust. I know EBC do front pads for the LS at £60+. Are they better that the OEM pads?

I am also going to change the brake discs themselves as I get a judder and whilst I am at it I will finally replace the parking brake shoes, so quite a brake overhaul coming up in the very near future.

How do the pad wear sensors work on the LS? I have had cars where the sensor wire is embedded in the pad itself so replacing the pad automatically replaces the sensor. Is the LS like this or have I to purchase more parts?

Trevor

Brake pad wear sensors are transferable to the new pads, they are held on by a metal clip which you have to gently prise off,push the sensor through the pad backplate and slip the wire through the u shaped cut.

They are suseptible to damage being in such a hostile environment and the wires can break off at the pickup (don't let the pad fall out of the holder as this can also break off the wires due to gravity and the weight of the falling pad!) you then have a choice either pay around £47.00 each at Lexus for a new one or cut back the insulation on the 2 wires, connect together and tape them up.

I think the principle of operation is that the sensors protrude from the pad backplate so contacting the disc before metal to metal contact ( and disc scoring) occurs,this will take the top off the sensor and the contacts inside will go open circuit causing the warning light to illuminate.If this has happened of course the sensors will need to be replaced ( or shorted out as above)

The latter option of course will remove the warning facility

[GoldfingerLS]

Hi TrevCooke, Chris,

I have a MK IV LS400 and here is my two bobs worth on the brake pads / discs issue.

Looking back on my past experience in trying different manufacturer pads (mostly with Honda Accords we’ve owned before buying the LS400), my opinion is that OEM pads are generally not worth it if the objective is to save money. It is for this reason when I came round to replacing the pads on the LS400 earlier this year, I chose genuine Lexus/Toyota pads. Allow me to explain why I have come to this conclusion.

In the past I have tried different brands of aftermarket pads on Honda Accords. Firstly in terms of pad wear rate, many of the aftermarket brands tend to wear very quickly. For example, I have used Lucas pads on the front which have lasted only 10,000 miles of driving and ADL pads which have lasted as much as 17,000 to 20,000 miles. (The mileage numbers here are based on approx 70% motorway driving and 30% town driving). Often in the past for me it has just meant that when I had purchased pads that only lasted for around 10K miles, although they had been £25 cheaper to buy than say genuine pads, I had just ended up paying the mechanic 2 visits (and hence two fees) over the 20K mile period instead of one, had I bought pads that lasted longer. So in real terms this did not really work out cheaper.

And what if using aftermarket pads did somehow work out cheaper, then what? Well, then there is the problem that cheap pads are (not surprisingly) made of cheap or coarse material. Often I have found that after washing the car, the faster wearing pads started to make the wheels black with heavy brake dust after only a day or two of driving. Another problem is that aftermarket pads may be made of a material with a heat/friction index which is not suited to the discs installed on your car. The result is that over time the brake pads may end up producing more heat than the discs can dissipate and cause them to warp leaving you to foot a bill for purchasing new discs and paying a mechanic labour to fit them. I noticed this problem because when applying the brake at motorway speeds, the steering wheel had significant shudder in it. (The problem disappeared after replacing the discs.) If the problem of excess heat build up is addressed too late, you may even end up ceasing one or more of the pistons in your calliper.

When I came round to replacing the pads on the LS400, I purchased a genuine set of pads from Toyota for £66.83 inc VAT. If I did not purchase genuine pads, I would most probably have gone for ADL Blue Print pads. Although I have not tried ADL pads on the LS400, it is because in my past experience the next best thing for Japanese cars if not genuine pads is ADL as they last very long and don’t produce huge quantities of brake dust every week, and have worked well on the Honda Accords for me without prematurely wearing out / warping the genuine discs.

I also got a price from Lexus for discs for the MK4 LS400, which if I can remember correctly was around £88 each inc VAT. When the time comes to replace the discs, I will most probably go for genuine Toyota discs. Over the long run, especially if I plan to keep the car long, I don’t think I will save much by going for aftermarket parts. You have to remember that the LS400 is a very heavy car, with 4 pistons in each calliper at the front, so the brake gets punished. I wouldn’t be surprised if many aftermarket pads don’t perform well and/or compromise your brake discs.

As for the sensor, Lexus charge around £50 just for the sensor. As Steve2006 mentioned, you can re-use the old one if it has not grinded away too much against the disc by replacing the wire loop through it with solid core wire. You’ve just got to carefully pry out the old wire.

Hope this helps. Let me know if you have any questions.

[chris vince]

Dear All,

This may help someone out.

I still haven't replaced my front discs as yet, I was going to this week having got a blinding quote from my local motor factor, when I went to snap his hand off and buy a pair at the silly price he quoted, a problem arose.

Quinten Hazell have withdrawn from sale all discs suitable for LS400's, we were unable to ascertain why.

So, if any owner has fitted QH discs recently, and is unhappy with them it may be worth chasing this up with the supplier.

Regards,

Chris Vince

[Mike Bristol]

Thanks all for the hints on brakes. I recently replaced my front pads using genuine Lexus parts. I was about to pick up a new sensor cable when I noticed the price. Thinking the parts assistant had mistaken it for a gold plated hi fi cable I asked him to check. Yes that was correct £52.70. So I let him put that one back on the shelf. I will try to dig the wire out of the sensor as mentioned above if not cut and join. I also get the judder on breaking so will soon replace the front discs.

BTW my reg is V400 LEX , not bad for the car