how to change brake pads on vivaro?

As I just completed the above, with no car manual available (can't get anything from the web here, very frustrating), I thought I would feedback here as a goodwill gesture from all the great help I did find from members of such 'how to sites' - I will only record some additional useful things I found out, as I think in other responses the technique required here is adequately covered:

1) front disc pad changing will I suspect be a little difficult if the discs are well worn, as usually there is a rusty ring at the edge of the disc which helps stop the caliper assembly coming away from the support...obviously the technique is some tapping with a hammer and wood on the brake cylinder part of the assembly to get it free from the rest of the caliper assemby, with the parts dropping off (of having to also be tapped out after tghe cylinder assembly is first removed)...however, as the discs are meant to be minimum of 10 mm thick, if that rusty edge is quite thick, it probably means that the disc needs replacing in any case - if not, and the pads only are replaced, then I personally tend to kock any rusty edge pieces off with a hammer, which aids to the pads going back in - one must put the cylinder back into it's caliper to enable enough space to take the new thicker pads.....I use a g-clamp, although when desperate have levered with a long socket bar, with a suitable piece of wood protecting the cylinder face...I think if either method does not work, it would mean that the cylinders might be stuck...personally I have never found a trulc ceased cylinder, and the cylinders I have pushed back need a reasonable ampunt of force, but you can pretty easily see if the cylinder moves a little - if it does, just keep pressing

2) On this occasion with the vivaro, I replaced also the discs - in theory they ere replaced just 2 years prior.....to cut a long stroy short, I spent 2 or 3 hours banging away trying to get a disc off, which was obviously a little rusted onto the underlying wheel hub assembly.....on the 2nd one I tried, whilst it did not 'fall off', it only took a few taps from a hammer - so my only suggestion is that some discs may be a very tight fit, and it will take alternate hits on the disc from behind, usually top and bottom, until a little movement is seen, and then perhaps taps at 120 degree intervals whilst turning the disc...on my 'stick disc' it took very many taps at all stages...I suppose a professional mechanic would have a better idea how hard to tap, but I did tap pretty hard with a short heavy hammer...I also used WD40 sprayed in the wheel holes and from the back, once I got a little movement, which seemed to help...as I said, on the 2nd one, 2 taps more or less got the disc off.......ibn case not obvious, to get the disc off, you first must take off the two largeísh bolts that hold the caliper frame to the car...I had already taken the wheel brake cylinder assembly/pads away (using the two smaller bolts), but I suppose it is possible to leave the wheel cylinder connected to the caliper frame, and just take the whole thing off (although to get the brake cylinder piston pushed back in you probably need to separate the bits in any case.....as I am a home mechanic, I have the time to be slow...I suppose a professional needs to be faster and may do it together

3) Rear discs......mine did not look too worn, but the MOT had advised change them.....then when checking the thickness, it is clear that on vivaros the amount of thickness is not very generous, and therefore, with only 1 mm of wear on each side, you probably need a new disc - unlike the front (as front wheel drive), the disc change is actually a wheel hub change also...in the past I have happily changed bearings and hubs, but when I saw the price difference online to buy replacement hub/disc units that already had new beraings (and the abs ring) fitted, then I just went straight ahead and bought that - the kit also included the pads.....very easy to change, i.e. just lever (actually I knock with a old screwdriver and hammer) the cap that covers access to the large nut that holds the hub in....take off the wheel brake cylinder, pads (as per front, i.e. tapping if needed, noting that it will be a little tighter because of the way the cylinders are held close to the discs given the automatic handbrake adjustment system.....then take off the caliper frame with the large two bolts - note when taking the small bolts out, you need to hold a nut which sits between the metal from the brake cylinder assemply and the caliper frame mount, otherwise you might twist the rubber sleeve which sits over the 'bolts holes'...actually when tightening, this is probably more important - if you find splits in the rubber, you should defintely change, as without these, the cylinder movement could rust up)...ok, back to the main nut holding the wheel hub on the car..... it is a 36mm nut, which is a large socket (most socket sets stop at 32 mm), and there is not enough room to get an open end, ring spanner etc etc in....lukcily for me I had just got from ebay a very large socket set for HGV's, i.e. with a 1 inch and 3/4 incl drive (my normal sets have 1/2 and 3/8'), with sockets that went all the was to 60 mm......I was intending to use a torque wrench to undo, so as to get an idea of what torque to tighten it to on re-assembly, but as this has only a 1/2 drive on it, I could not see a way to do it, so instead, I tried different length socket bars (my set allowed me to try 3 different lengthes), to give me a rough feel for how tight...it IS a anti-clockwise turn (standard)...I did wonder as it did not undo easily - I in the end used the longest bars I had (on my system can be put together), which gave me something like 1.2 metres leverage, and with quite a lot of effort, it came off smoothly) - I note that on other veciles I have (unimogs), which have very heavy and tíght nuts/bolts, I usually get away using my smaller 3/8 socket, with my standard t bar, but this placed into a longish hollow tube that I take from my trolley jack handle, and this shifts (with quite some muscle) very tight nuts.........once the nut is away, my hubs dropped off easily, if tight (probably unlikely), some knocking would I assume free easily, as there is not really a way for the area to become rusted (since my vivaro is only 5 years old, I assume this to be the case)....placing the new hub-disc assemly on is a simply push (one of mine was tighter than the other and had to be pushed by hand with a little force, whereas the other slid on smoothly...don't worry about greasing anything, as the bearings come pre-greased....on tightening the nuts, they have a 'drag' as the end of the nuts have a squashed head, to sopt them coming loose in service...with a large socket on however, this is not too hard to tighten....do use the new nuts that are provided in the hub kit.....I found that with a standard socket tbar length, the nuts went tight pretty quickly, and the hubs went from feeling 'loose' to rotating nicely, but no lateral movement´...when I tightened with my longer tbar, it also went tight with very little movement, so I concluded that perhaps the torque is not so critical (if another reader has the torgue information, and you have the torque wrench with adrive that fits your 36mm socket, then obviously that is a better method to use)

4) once both hubs are on, you need to wind back the brake cylinders....they wind back clock wise,....I did by the winding kit, as it fits very many different vehicles, and I found it easy to use, although you need to be sure to use the right direction tool (i.e. kits come with clockwise and anti-clockwise tools, and mine had both) - I am sure using pliers would also work, proving the cylinder turned...on mine, one cylinder turned fairly easily, and I think pliers would have been fine - on the other one, however, it was a really hard slow turn, and I was glad I had the tool.....only thing to be careful (with or without tool), is to not damage the rubber around the cylinder, and to make sure it is turned all the way in (pretty obvious as it more or less does just stop, and is also almost flush with the surrounding metal)...once the cylinders are wound back, attached the caliper frame with the large two bolts, place the pads into this (they may need a littkle tap to get them fitting all the way in, and push on the wheel brake cylinder assemby over the new pads and disc....when tightening the smaller two bolts that attach this, don'T forget to hold with a second open wring spanner the nuts into which the bolts also turn through, to avoid twisting/splitting the rubber 8as well as to get them properly bolted down fully)....always hand tighten first, as normally it is a fiddle to get the wheel cylinder unit sitting exaatly in the right place.....I also did not have the torque for these bolts, so basically used two differnt lengthed ring spanners for the final tightening (on the basis that a shorter one tightens the smaller bolt) - in either case, they should be tight, but not so that your hands hurt


...you can adjust the rear cylinders by a few pulls of the handbrake, a cautious test drive, light braking and a few more pulls, and hopefully all the pads and adjustments occur...

Not a difficult job...but, when I did my jeep discs the following day, I did not have any trouble taking them off (they just 'fell loose'), and I did not need an hgv sized socket to do it.....I am sure a professional mechanic would do all 4 wheels in around 2 hours max...I spent probably 7 hours in total, although if I did it again with the knowledge I have now, I am sure I would mange 3 hours......

Hope that helps...