Technical Warm rear wheel - caliper issues

[Jamie KC]

I've been struggling to get as close as usual to 60mpg for the last week or so, and occasionally it felt as if the car wasn't rolling as freely as it ought when coasting clutch down on flat ground. Twice now when arriving at work I have put my hand against all four wheels, and found three being relatively even in temperature, but with the OSR being noticeably warmer. Clearly this means the pads are remaining in contact with the disc, and the rust rings on the disc point to this too.

Although the pads aren't low, I've ordered a pad set with replacement steel inserts for the caliper that the pads sit against. I've also ordered new slider pins for the caliper to run on, and will lube the piston before winding it back.

Is there anything else worth bearing in mind specific to the calipers on a Panda 4x4, or any advice worth following when giving these an overhaul?

 

[Herts Hillhopper]

Yes - they’re a bugger to remove! There’s a great thread somewhere about how to do it, and suggestions it takes a day’s time. I paid The Fiat Workshop in Royston, North Herts who charged just one hour’s labour to replace rear pads and discs. Apparently they take the rear hub nut off and take the whole unit off the car instead of the dismantling process described in YellowCar's post - see here https://www.fiatforum.com/threads/4x4-rear-brake-discs.437398/post-4377889 (its worth reading the whole of that thread for background as well)

 

[Herts Hillhopper]

Yes - they’re a bugger to remove! There’s a great thread somewhere about how to do it, and suggestions it takes a day’s time. I paid The Fiat Workshop in Royston, North Herts who charged just one hour’s labour to replace rear pads and discs. Apparently they take the rear hub nut off and take the whole unit off the car instead of the dismantling process described in YellowCar's post - see here https://www.fiatforum.com/threads/4x4-rear-brake-discs.437398/post-4377889 (its worth reading the whole of that thread for background as well)

By the way, lots here swear by smearing copper grease etc all over. Personally I don’t like that: grease + brake dust = glue, making things stick. Mine have never been greased - even the backs of the pads (front or rear). But do get a good blast from the hose on the rare occasions I wash the car. Keeping accumulated mud or brake dust off seems to do the trick. Old rear discs were perfectly shiny and all pads equally worn prior to replacement, and the new ones still all in great shape 6 months on.

 

[Panda IIs]

Yes - they’re a bugger to remove! There’s a great thread somewhere about how to do it, and suggestions it takes a day’s time. I paid The Fiat Workshop in Royston, North Herts who charged just one hour’s labour to replace rear pads and discs. Apparently they take the rear hub nut off and take the whole unit off the car instead of the dismantling process described in YellowCar's post - see here https://www.fiatforum.com/threads/4x4-rear-brake-discs.437398/post-4377889 (its worth reading the whole of that thread for background as well)

I think the tricky bit is just the disc replacement (removal of the calliper bracket is the issue, to release the disc) I think @Jamie KC is only planning to swap out pads and pins? You do need to wind the piston back in on each side (handbrake) for which you can buy a tool but I managed with judicious pressure applied via a g-clamp while rotating the piston with an adjustable spanner (don't grip the piston on the OD and destroy the sealing surface).

 

[Herts Hillhopper]

I think the tricky bit is just the disc replacement (removal of the calliper bracket is the issue, to release the disc) I think @Jamie KC is only planning to swap out pads and pins? You do need to wind the piston back in on each side (handbrake) for which you can buy a tool but I managed with judicious pressure applied via a g-clamp while rotating the piston with an adjustable spanner (don't grip the piston on the OD and destroy the sealing surface).

Ah yes - in which case, not so bad.

 

[Jamie KC]

Thanks gents. Yes, plan is to replace pads only, as well as the carrier pins. But, I am now in a quandary; do I copper grease the surfaces (original plan), or leave them dry (newly considered plan)!

 

[Panda IIs]

Thanks gents. Yes, plan is to replace pads only, as well as the carrier pins. But, I am now in a quandary; do I copper grease the surfaces (original plan), or leave them dry (newly considered plan)!

Ah, well you could do a controlled (ish) experiment and grease one side and leave the other dry - then report back here in two or so years time!

Very useful data to have Mine were greased! But with high temp brake grease.

 

[TTR]

Eh up,

My view and I’ve stripped mine a few times is use red rubber grease on the sliders

Copper grease solidifies and should not be used as a grease in this application

Mine have remained free and even

Cheers

 

[Jamie KC]

Eh up,

My view and I’ve stripped mine a few times is use red rubber grease on the sliders

Copper grease solidifies and should not be used as a grease in this application

Mine have remained free and even

Cheers

Have this, will use

 

[The Panda Nut]

My experience is ONLY use sspecific brake grease on slider pins, NEVER copper grease. I use Bosch brake grease and have never had issues with slide pins.
I have had issues with the rubber sleeves on slider pins going soft and suggest these can be a problem. I think the two slider pins in the rear brakes are different, one has rubber sleeves and the other doesnt. Dont get them mixed up or it will cause issues. If the piston has become sticky, I would bite the bullet and fit a new caliper as once they start to stick its a down hill battle.
A little copper grease on the back of the pad where in contact with the piston helps helps reduce sqealing risk but dont use anywhere else. I have now a supply of aluminium based grease for pads. It basically dries and seems to stop pad edges rusting or becoming sticky. Koalar recommends dry assembly and I strongly suspect he is on the money. Just use copious anmounts of brake cleaner to get rid of black dust.

Sick of rusty discs on our 169 I have recently had the calpiers changed, and the problem has been resolved hence my suggestion on replacement. Maybe give it one chance for a working fix first.

 

[Big gerry]

Ah, well you could do a controlled (ish) experiment and grease one side and leave the other dry - then report back here in two or so years time!

Very useful data to have Mine were greased! But with high temp brake grease.

Yes so did I the high temperature grease in my opinion is a better job than copper grease

 

[Herts Hillhopper]

My comment was there’s no grease of any sort on my pads, callipers etc. All assembled dry, just as they are in the factory, and - so far - never seen any issues. But, my car gets a reasonable amount of use, often carrying load in the boot: this I believe keeps the brakes in good order. The rear disks on little-used 4x4s do seem to suffer for not having near-daily exercise

 

[WitleyPanda]

Depending on where you source the pads, you may get a sachet of pin lubricant., which looks similar to red rubber grease As for backs of pads, use white ceramic grease is the standard but dry OK particularly on the panda. If there any issue with the disc, it worth the hassle of changing as from experience the problem re-occurs. Obviously if you change one side, just pads or discs you need to do both sides of the vehicle. It useful to compare the wear/thickness of all four pads as it will help you identify root cause. In my case it was lack of clearance ( tolerance on parts) between the tag on the pad to stainless steel channel to calliper groove. I changed brand of pad, which came with better stainless steel parts with built in return spring element and the pin lubricant. All good now and knowledge gained. [ Car now does 60-80+miles a day, rather than a few thousand a year which helps.]