Lexus Health Check - Seized Rear Calipers

[BillNick]

Hi all,

My 2008 IS250 went in for the 2x recalls on Monday and as you would expect Lexus performed their free vehicle health check.

All green ticks apart from the rear brakes. Rear pads low (after only 13k miles from new) and rear calipers seized. I guess the pads which were fitted new 13k miles back have been worn down by the seized calipers?

I know this is a common fault so wondered is it more likely to be the slide pins than the caliper pistons themselves? If so, I assume a new slide pin kit  with boots and grease from a brake repair supplier will do the job? I will replace the discs and pads at same time too.

I will check the movement on the pistons to but without getting the wheels off yet just wondering what cost is more likely. New slider kit or new caliper?

Thanks

[baviaannl]

21 minutes ago, Billnick said:

Hi all,

My 2008 IS250 went in for the 2x recalls on Monday and as you would expect Lexus performed their free vehicle health check.

All green ticks apart from the rear brakes. Rear pads low (after only 13k miles from new) and rear calipers seized. I guess the pads which were fitted new 13k miles back have been worn down by the seized calipers?

I know this is a common fault so wondered is it more likely to be the slide pins than the caliper pistons themselves? If so, I assume a new slide pin kit  with boots and grease from a brake repair supplier will do the job? I will replace the discs and pads at same time too.

I will check the movement on the pistons to but without getting the wheels off yet just wondering what cost is more likely. New slider kit or new caliper?

Thanks

My money's on the pins, Lexus wont touch them and prefer to list the calipers as needing replacement.  If you're competent, jack the motor up and remove the pins giving them a good grease.  I do this as part of a 6 month maintenance schedule when I also change the oil, not a long or difficult job at all.

[BillNick]

Let's hope they budge and I CAN get them out/off 🙂

[baviaannl]

4 minutes ago, Billnick said:

Let's hope they budge and I CAN get them out/off 🙂

If you smack em hard enough... they'll come out 😄

[normski2]

2 hours ago, Billnick said:

Hi all,

My 2008 IS250 went in for the 2x recalls on Monday and as you would expect Lexus performed their free vehicle health check.

All green ticks apart from the rear brakes. Rear pads low (after only 13k miles from new) and rear calipers seized. I guess the pads which were fitted new 13k miles back have been worn down by the seized calipers?

I know this is a common fault so wondered is it more likely to be the slide pins than the caliper pistons themselves? If so, I assume a new slide pin kit  with boots and grease from a brake repair supplier will do the job? I will replace the discs and pads at same time too.

I will check the movement on the pistons to but without getting the wheels off yet just wondering what cost is more likely. New slider kit or new caliper?

Thanks

I'd hazard a guess and suspect the lower pin on the rear calipers. They can be quite a toad to free up.  If it is the bottom pin that's seized, get the top pin out and try to rotate the caliper back and forth until it frees up enough to be removed. If you're lucky you may be able to clean up the pin and the socket (emery cloth is good, or plain old sandpaper) it goes into, re-grease and re-assemble. Don't forget to use Red Rubber Grease for the slide pins.

This guide by Noobie will give some pointers.

 

[BillNick]

Nice one, thank you. Will have the rubber mallet to hand!

[normski2]

My rear was so bad I had to lever it with a short crow-bar to get it to move!!!

[BillNick]

Ouch! I think mine will be the same.

It has seized on those bottom pins before. When I had the rear pads fitted the mechanic called me up to explain he had spent 45 mins trying to free the bottom pin and I might need a new caliper. Eventually he got it free'd but I guess he didn't spend much time cleaning it up etc as they seized and eaten the new pads.

Hopefully I can get it off myself and clean up properly overnight etc.

[steve2006]

Pull the rubber boots back and get some WD40 in there overnight.

[is200 Newbie]

Its going to be the bottom pin thats siezed. The top pin is actually a bolt and is shrouded in a plastic boot.When the bolt is removed then the caliper should pull out and down towards you - when its reached a point of release (clear from the disc) it will pull out.

Your cause is going to be failed rubber boots that cover the pin from the weather - if you do manage to free the calipers then make absolutely sure that the rubber boot securely seats in the groove on the caliper. Chances are you will probably find that the boot had lost its elasticity and wont securely sit in the caliper groove.

I think in a lot of the cases of siezed calipers its down to the choice of grease used - owners like to experiment or use what they can find in their garage for their pins. Its a bit of an expensive gamble. I have used the Toyota red rubber grease which acts as a lubricant for the pins while not attacking the rubber boots. I think a lot of people go for the brease that is good for the lube of the pin itself without considering the boots which do actually come into contact with a lot of the slide pin grease. I have used the Toyota grease now since 2008 with absolutely no issue and not about to change as it works. No doubt someone will comment on other types they use but this for me is meant for the job.

All the tools you need to remove the rear caliper is a standard size 19 socket and to be honest its a simple job you can do yourself if you have the space to do it. Its best to keep both rear and front calipers greased. Mine are done twice a year but i guess you can stretch this to once a year. Its handy to know how to do it to stop them siezing.

[is200 Newbie]

This is what you want - part number is current also

[johnatg]

All sound advice.

Re pad mileage - 13k miles isn't totally unreasonable - IS250 etc does tend to be a bit heavy on rear pads

(And front ones - expect to need a change at anything over 15k miles.

Sent from my PSP7551DUO using Tapatalk

[BillNick]

Indeed, thanks very much for all of your advice everyone.

Will get to it next weekend.

[is200 Newbie]

Also, if its not budging you can carefully try adding some heat over the housing on the caliper where the bottom pin is located in as it can take some heat but be carefull - it might just be that bit of extra "oomph" that you need to free it.

[Eddy555]

Had the same, one caliper seized. To be fair the £270 they quoted for a replacement caliper fitted seemed pretty fair for a main dealer.

However I fixed it with some brute force. A bit of heat on the bottom of the caliper and then a lot of decent hits with a drive punch (Link below) and hammer just above the slide pin got it freed.

https://smile.amazon.co.uk/dp/B000LFVNNM/ref=cm_sw_em_r_mt_dp_U_.5O4CbCWAF4YD

Water had got in and corroded it quite a bit. I didn't have new ones to hand, so cleaned up the hole and pin and gave it a good greasing and it's free now. I'll replace the pin and rubber at some point this year though.

This is the grease set I've bought for the using on the Lex

https://smile.amazon.co.uk/dp/B07886FP12/ref=cm_sw_em_r_mt_dp_U_l9O4CbB4BPJBT

[BillNick]

Great, thanks very much for even more feedback.

Seems a common fault.

Is anyone able to explain to me how the pin seizure in this place will effect the operation of the rear caliper & brakes please? Clearly it does, I am just curious as as far as I can tell the pin is lubricated only to make removal easier? Is that correct or not?

[Britprius]

When the slide pin seizes the caliper cannot move sideways to pull the pad on one side against the disk as the piston pushes on the pad the other side. The caliper only has a piston on one side so needs to be able to slide sideways to apply both pads to the disk.

Seized slide pins tends to ware the pad on the piston side, and flexes the disk towards the other pad. When enough pressure is applied to the seized slide pin it operates as it should but then does not release the the none piston side brake pad causing brake drag.

The front calipers have pistons on both sides of the calipers removing the need for slide pins, but gaining complexity by having multiple pistons, and hydraulic seals.

John.

[BillNick]

Perfect thanks John.

Sounds like this could be causing the sticking sensation I am getting upon hard braking?

It feels like the brakes are only making contact on part of the disc and as that part of the disc passes through it is 'grabbing' the car rather than smooth and consistent slowing down of the car??? Kinda like warped discs but on the rear so no steering wheel vibration....

[Britprius]

2 minutes ago, Billnick said:

Perfect thanks John.

Sounds like this could be causing the sticking sensation I am getting upon hard braking?

It feels like the brakes are only making contact on part of the disc and as that part of the disc passes through it is 'grabbing' the car rather than smooth and consistent slowing down of the car??? Kinda like warped discs but on the rear so no steering wheel vibration....

Seized slide pins can cause warped disks as in extreme cases the disk is bent by the hydraulic pressure being applied to one side of the disk via the pad with no opposite force from the pad on the other side of the disk. I have seen vehicles where the disk or part of has completely broken away from the supporting hub.

John.

[BillNick]

Thanks John.

I plan to replace the discs and pads when I rectify the slide pins, hopefully this will cure the braking sensation/efficiency issue.

Thanks again, always helpful to learn from another members experience.

Billy

[Britprius]

When you replace the rear disks check the condition of the parking brake shoes "mounted in the drum inside the disks". These shoes have very little brake lining on them when new probably only 3 or 4mm. They tend to ware at one end of each shoe. If the linings are worn close to the shoes at one end replace these at the same time as the disks, and pads.

I bought Ferrodo shoes for around £12 the set on eBay or it may be worth buying some on sale or return from your local motorist shop as it is annoying to find you have the car in bits, and not have everything you need to hand. 

John.

[johnatg]

The front calipers only have one piston - they slide (and seize) just like the rears. But the slide pins are effectively bolts and have hexagons, so you can release them with a suitable spanner and if necessary a bit of wellie. Also they are less likely to seize than the rears as they do more work so keep moving more.

Rear shoes shouldn't wear at all - they only wear if you drive off with the parking brake applied. You never do that, do you? 😉

[Britprius]

I stand corrected on the front calipers, but on my Lexus they are 4 piston calipers with pistons on both sides. I agree in principle the rear parking brake shoes should not ware, but in practice on vehicles with 70k plus miles the shoes are often due for replacement.

It is not unusual to find the bonding between the lining and shoes to be parting, and I know of several instances "not all necessarily Lexus" but other vehicles like Volvo, and BMW with the same systems where a rear wheel has locked due to shoe linings becoming detached. 

John.

[johnatg]

Indeed - I had a rear lining detach like that on a Pug 205 of my wife's years ago - ended up destroying the brake hub in getting it off. So yes - I do agree, they need checking and possibly replacing even on cars where the rear shoes only operate as a parking brake.