octagone

Updating this thread after I've done the job in hopes this can help someone else in the future. Replaced both rear calipers, on Autodoc I filtered by "TRW" brake system and then chose TRW-branded ones - these were correct. And in fact they were refurbs of the OEM part that I pulled off the Octavia - happy days. Cost a bit more than other manufacturers, but going OEM never hurt anybody. I spent a lot of time looking at what size banjo bolt/washer size is needed - nothing official online, the ones in the Halfords variety pack I bought looked too skinny (ID 12mm OD 14mm) - I was right, the washers I pulled off are ID 12mm OD ~17mm. I used ID 12mm OD 18mm Thickness 1.5mm washers - these worked fine. Don't go less than 17mm OD or the washer will be thinner than the flange of the bolt. Also found it difficult to find a torque spec for the banjo bolt, you'll see anywhere from 20nm-40nm online for other makes of cars with 10 or 12mm bolts. I went by feel balancing "will this leak" with "will this snap", while also firmly tapping the bolt head with a ball-peen to seat the washers. Checked the torque after and both are coming in at around 35nm. No leaks and the driver's side disc is now wearing down properly so that's solved the binding!

If "slider" is the guide pins on the caliper - both sides moved freely and the boots looked OK. If it's the mounting bracket, which I can't remember if the caliper should move along this - yes it's quite rusty and I didn't give it a thorough clean or grease (if there's anywhere sensible to grease contact points of mounting bracket + caliper). I focused on cleaning the contact points for the pads, which I did manage to get to a high standard - nice and smooth. I'd hate to have to remove the mounting bracket, the bolts are almost certainly seized and my ego can't take stripping another bolt head on this car For which brake system I have, looking at llparts and previous forum threads while nobody mentions Lucas/TRW or calipers themselves it's often suggested that 1KD with 253mm discs will be TRW system, and given I can't notice any difference between the two parts I'm growing confident that I should be getting TRW calipers. Hopefully someone will chime in saying for sure. I'll have a go at cleaning the caliper and contact points more thoroughly, and inspect the piston since that might allow me to actually leave the house this bank holiday weekend, but I'm suspecting the final solution will be replacing the calipers.

I don't currently need the car, and I'm avoiding driving it while it has brand new discs & pads on since the stuck caliper is very obviously wearing down the driver's side disc incorrectly - it's seen about 10 miles since I replaced them - but looks to have done no damage other than half the diameter of the disc is the factory coat still. If I find I do desperately need it before I get a chance to replace the calipers then I will look at giving the pistons a clean. Is it possible to clean the pistons without completely removing them? In my mind half the labour involved is going to be introducing air to the brakes and having to bleed, which is what I'll have to do if I replace the calipers, anyway. Can the rubber piston seal be pulled off the piston (while it's fully rewound) and cleaned?

Rear brakes binding, cleaned everything, removed and replaced some very seized pads on both sides and replaced some quite tired discs on both sides. Passenger's side works perfectly, driver's side still binding. Rewinding the pistons I did notice that they were looking worse for wear but I already had discs & pads and was a bit too hopeful - need to replace or refresh the calipers. Looking at calipers on autodoc, I can see TRW or "Lucas/TRW" brake systems as options. The only difference being that "Lucas/TRW" is twice the price. I've got a 1.6TDI DDYA engine, 1KD code for brakes with 253mm rear discs. On the caliper itself enscribed is "VWAG, GNO, TRW" and the piston diameter is 38mm as seen on the calipers. Both "TRW" and "Lucas/TRW" options match those fitment details. How am I supposed to know which one? Does it matter? Cheers!