A very very hot back wheel and even hotter disc

[andyKent]

Originally Posted by cheshired5

That's fair enough and all part of the learning curve.
That said, you will still find seasoned mechanics clamping hoses.
Even if you were winding/pushing in a piston, you alleviate any pressure by opening the caliper bleed and allow the fluid to escape there.
The fluid in the caliper has had a hard life and is the worst quality in the whole system so you want it out and refreshed not pushed back up the pipes and reused.

Yep, that makes sense - I hadn't thought about the stationary nature of the fluid but I guess since it doesn't circulate (get pumped) around, then the fluid in the caliper probably does get the worst punishment through heat/dirt/etc.

I gave the car my regular motorway run today. Last time I did this exact same run (there and back, with some gentle hills, each way 60 mins at 75 mph) I struggled to get 30 mpg average.

Now back to 45 (and that's on Goodyear Wranglers). Hooray!

Andy

[Mistero]

I noticed a slight deterioration in performance over the last week or so, then burnt my finger tips on the offending brake disc (driver's side rear).

My life is v busy at the mo trying to keep a promise to my wife that she'd have a new kitchen in time for Christmas, so last Thursday I turned up unannounced at P&R Cars in Leeds at 8am.

As per others on here, problem was a sticking calliper.

An exchange calliper, new set of rear brake pads both sides and a brake bleed for £285.

Fixed that day. I couldn't thank them enough.

I recommend the garage wholeheartedly.

[Malcolmoliver54]

Today I have just replaced both rear callipers ( Recon from local motor factors).....Same symptoms... Both rear wheels getting very hot and smelling. Bought car in November with new MOT... new pads had been fitted... took car back to dealer who arranged for new parking brake shoes... seemed to partly resolve problem as wheels only became warm on short journeys ..however problem didn't go away completely and then a couple of days ago I noticed pads down to metal... hence a new disc and both rear callipers done today..... Went for test drive and all working well.... however the ABS needing service warning comes on ... as it has done for past few days.. so guess a trip to somebody with diagnostic machine to hopefully get the system cleared...unless it may be another unrelated problem.

[4candles]

If you just pumped out the pistons out of the calipers you would of found crud on the pistons, easily cleaned off with some fine scotchbrite. No need for expensive 'remanufactured' calipers.

Just did a friends, with the handbrake type calipers, so easy and so cheap.

Bit of a faff getting dust boots on but saved him a small fortune, all working perfectly and sailed the MOT.

[galloot633]

Sadly, on mine the pistons had rusted, stripped , cleaned and greased, but only lasted a month then seized again
Dave

[andyKent]

Originally Posted by Malcolmoliver54

Today I have just replaced both rear callipers ( Recon from local motor factors).....Same symptoms... Both rear wheels getting very hot and smelling. Bought car in November with new MOT... new pads had been fitted... took car back to dealer who arranged for new parking brake shoes... seemed to partly resolve problem as wheels only became warm on short journeys ..however problem didn't go away completely and then a couple of days ago I noticed pads down to metal... hence a new disc and both rear callipers done today..... Went for test drive and all working well.... however the ABS needing service warning comes on ... as it has done for past few days.. so guess a trip to somebody with diagnostic machine to hopefully get the system cleared...unless it may be another unrelated problem.

Sounds like the pads were already shot due to pre-existing failed calipers, pads replaced for MOT but destined to fail anew, and duly did. I'd bet that 'somebody' greased the stuck calipers after noticing wrecked pads, replaced the pads and said 'needs new calipers but it'll last long enough for the MOT and sale'. In fact, I'd guess that seized calipers would not get noticed during MOT unless the pads were wrecked and even then it would be the pads that caused a fail (so easy to remedy by replacing pads).

Unless the heat of the wheel(s) fried the ABS sensor(s), there's no reason to assume that the seized caliper and ABS warning are necessarily related, excepting that they are both things that apparently and predictably go wrong somewhere near the 140k service point.

Based on what I have read around here and experienced personally, the ABS rings and engine mounts should be part of the 140k service (if not nearer the 120k mark). I guess it's pretty obvious to any engineer that these components can't possibly last indefinitely (unless the car is never driven and is stored indoors).

In my xc90, the front headlight main bulbs failed within 1000 miles of each other. The mounts and ABS rings and rear caliper failed within 4000 miles of each other. You could easily interpret this as 'concurrent failure' and wonder about the amazing coincidence.... My take is that this is a well engineered machine and so failures are quite predictable - we should be surprised if they didn't happen on time. Who'd expect the cam belt to last 140k?

So, the take home message is: check (or change) front ABS rings before spending the money on stab-in-the-dark electronic code reading-based diagnosis as it will not be able to tell you 'the ABS rings are shot' (and they probably are).

Andy

[WrathOfKain]

Originally Posted by cheshired5

I would never clamp a brake hose.
Most that I see aren't squishy rubber that just pops back to shape but in fact have a metal core so if you clamp it, you risk permanently deforming the core and restricting fluid flow.
You're also not going to lose that much fluid anyway if you leave the reservoir cap in place and let the hose hang and any small amount lost is replaced by the new fluid you have on standby.
The metal core in the hose is also a reason why braided "upgraded" hoses are a waste of money and are probably only worth doing on motorbikes, where standard hoses can still be a bit last century.

Strangely enough not long finished watching a chap on utube who did exactly that in his "how to change xc90 caliper" ..... crikey makes you wonder.

[Clan]

Originally Posted by WrathOfKain

Strangely enough not long finished watching a chap on utube who did exactly that in his "how to change xc90 caliper" ..... crikey makes you wonder.

Don't worry , In my 50 years in the trade I've never seen a brake hose with a steel core, remember that are constantly moving and twisting as the car goes along . they are rubber with a fibre reinforcement inside half way through it's thickness , the hole through the centre is just 3mm diameter. Brake hose clamps are a professional tool . what can happen on a very old hose is that the crushing by the clamp could close up the hole in the middle and restrict it , but never seen that yet ! If you get a hot brake on a volvo its the caliper sticking , no amount of cleaning or new piston is going to fix it for long , ALWAYS fit a new caliper and forget about it ... a sign of an overheated disk is an orangy colour of the disk metal .