This Jubilee bank holiday see's me finally swapping out my noisy power steering pump & replacement from disc and pads.
PAS Pump all swapped and bled up, jobs a gooden.

Then we move onto the brakes.......old pads and discs off, new discs on, pushed back caliper pistons as far back as they would go with a G clamp and block of wood (with the brake fluid res cap undone) + I cleaned up the calipers a bit.

I then inserted the new Brembo pads into the caliper carriers, I then went to fit the caliper over new pads but I was not able to fit the caliper over the new Brembo pads.

I then removed the caliper again and was able to push the caliper pistons back another small amount using the G clamp once again, but still I was not able to get the caliper over the new Brembo pads.

Click image to enlarge

Remote diagnosis is never easy, but......Wracking what brain cells I have left.....
Compatibility issues between parts?
Brake carrier not scrupulously cleaned up, deposits left? Rust scale deposits can be very thick. Use of hammer and chisel is not uncommon to remove deposits that look like metal.
Stainless spring plates incorrectly fitted ?
Incorrect parts in box by accident from maker / factory?
Not the right pads? - 5mm does seem excessive.
Wrong parts for model / year? - Do not know the part numbers myself.
May sound daft, but please do not take offence - G clamp at the end of it's travel / thread damaged, will not go further?

I know what will happen next, the next 'postee' will post the obvious answer that I missed

When you solve the problem, please post your answer / solution

Thanks for your reply, yes I did use a G clamp that was suitable for the job, parts definitely the right ones

Merchy ! - you have hit the nail on the head in fact.
Even though I cleaned up the caliper carrier, it was the outer piston itself that was covered in and rust (Offside)

Before I tackled the rusty offside caliper again, I decided to take a stab at the nearside to see what that side was like. Turns out its had a new caliper at some point on this side, as we can see by the distinct lack of rust inside the chamber there.

Click image to enlarge

Click image to enlarge

The state of that piston l would be changing the calliper before it causes you trouble. Don’t ask me how l know.

The calipers could also be over hauled using new pistons / seals.

When metal oxide ( Rust ) layers build up, there is quite an expansion ration from metal to rust, if memory serves me correctly with basic mild steel the expansion ratio can be up to 6 to 1, so lose 1mm metal and you could gain 6mm of rust.

In the past ive sent motorbike calipers away for overhaul at a specialist due to leaky seals, and on other motors ended up swapping calipers if either A bleed nipple is ceased or B handbrake sticky. I hadnt seen this much surface rust on a piston before upon closer inspection as recommended. I guess if the piston pushed back originally all the way I wouldnt have even wrote this post .

Ive also got a 200.000 touran that I wasnt able to successfully undo the bleed nipples on both front calipers due to rust but the pistons didnt look anything like the ones on this range rover.

Braking performance is still as good as it was before on this old girl, and now that shuddery steering wheel is a thing of the past when breaking.

Also ended up tightening the handbrake up a bit as we were almost 9 clicks up rather than the 7 as the manual stipulates (which even then is quite high)
Also had my MOT guy say yr before last that it was advisory, showed him the workshop manual stating 7 clicks. Current Fleet

FF L322 2.9TD6 SE
BMW e46 330ci Msport
Skoda Superb TDI Mk2, stage 1
Audi A3 8P 2.0 T 4x4, stage 2
Yamaha R6 13S
Triumph Thruxton R
Sold, but not forgotten

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