Fitting new Rear Discs & Pads to 3rd Gen RX450h

[Barry14UK]

Looking for a bit of advice from somebody who has done this or definitely knows what is involved.

I replaced the fronts last year having watched several videos where some suggested just pulling two relays or disconnecting 12v Battery and keeping key fob in Faraday cage. Some suggested doing all of these things which I did, although others say it was not all necessary.  I did not bleed the brakes and did not use Techstream.

I now need to do the rears and again there is some conflicting info on some of the videos.  Generally these refer to the 400h and are from outside the UK.  I understand that Techstream is needed to change brake fluid and bleed the brakes and I will get Lexus to do this at the next service but I would be grateful if somebody could confirm whether I can do the disc and pad change without Techstream and if there is a prior requirement to disconnect 12v Battery and or relays.  Lastly, are the pistons in the rear cylinders the wind back ones as fitted to some cars or can they just be compressed like the fronts?  Many thanks.    

[J Henderson]

The pistons can be compressed.

In theory you can change the discs and pads without the fluid being affected, outside of removing the reservoir cap to make squeezing the pistons easier. Hopefully someone with a hybrid can confirm.

[kenhall]

I did this job on my 400h recently to replace a badly rusted rear disc + pads (partly caused by salty winds from living near the Irish Sea) and didn’t take any extra precautions. Removing one of the caliper slide pins was a problem due to some corrosion and the rubber grommet on the end becoming dislodged. The other frustrating part of the job is adjusting the handbrake shoe clearance by poking a screwdriver through the drum to turn a star wheel which you can only locate by feel.

[Redefined]

Hi Barry. I remember watching the vid from Car Care Nut about 'all things Toyota/Lexus brake/brake fluid'. I don't have a hybrid myself but I remember him mentioning 'do not open the doors (or maybe just drivers side door)'.

 

Sounds like you're already in the know, but if it might be of any help I can dig out that vid for you. He's very thorough in most things Lexus/Toyota.

[ColinBarber]

The official way is to disconnect the two connectors from the brake booster.

 

Normally if you keep the doors closed and put the key inside, so it is no longer detectable by the vehicle, then you won't get an unexpected pressuring of the system.

[#Sandy#]

I disconnected the Battery first. One side came off easily when the shoes were fully retracted. The opposite side had built up a severe ridge to prevent the disc damaging the shoes. The use of an angle grinder and cold chisel later,the  hub could be assembled without any issue. Best of luck.

[Barry14UK]

Thank you for your responses.

Hopefully. discs will come off without too much of a problem but am aware this can happen from my days when my rear brakes only had shoes.  It was really precautions that have to be taken to avoid so as to avoid adversely affecting the car's electronic that was my concern.  Colin has kindly provided the answer. 

As the weather is now deteriorating and I have to work on my drive, I thought I would get a price for supplying and fitting with new pad shims from  Toyotech at Redhill, a forum recommended independent, as I am due to spend a few days fairly near there shortly.  I was surprised that the quote was for just over £400 which is a little more than what a Lexus main dealer quoted. I also asked for a price for an 8 year service and was told that they would also likely be more expensive than a main dealer for this too.  I was under the impression that independents were significantly less expensive than main dealers! This was certainly the case with my BMW where the labour rates were half of those of a main BMW dealer.

Anyway, my car has just passed it's MOT with an advisory on the rear discs and pads but tester thought like me immediate replacement was not essential.  I have therefore ordered the discs and pads from Lexus Parts Direct who have an offer on them for £184 at present. I think you will have great difficulty in getting a lower price for genuine parts unless you have a trade account.  I also ordered the shims as when I replaced the fronts, I found the inner ones had corroded into holes.  This was an extra £29 or so.

So all I need will be a fine day! 

 

 

[ColinBarber]

16 minutes ago, Barry14UK said:

I was under the impression that independents were significantly less expensive than main dealers! This was certainly the case with my BMW where the labour rates were half of those of a main BMW dealer.

Indeed. I see no point using them if they are more expensive than any main dealer who has better access to the latest information, more exposure/experience to vehicles/faults and provides a service history that is more valuable to the resale value of the vehicle. Plus you would be getting a hybrid health check and 12 month Relax warranty with a main dealer. 

[Barry14UK]

I agree with all you say Colin,

I think the person I spoke with at Toyototec was rather piqued by main dealer price for the rear brakes being less than theirs and the comment about expecting the Lexus dealership being probably cheaper than them for service was probably a throwaway remark.  They subsequently quoted £328-12 which is not bad for the 80,000 mile service.  The discounted price from Lexus is £560.  However, at main dealership a £60 health is included plus the Relax warranty, so when you take this into account and the cudose of a full dealer history, I think the extra cost is worthwhile, at least while there is still good equity in the car.