Thursday 23 August 2012

Vauxhall Vivaro rear hub nut and brake dices replace


This post has been prompted by the lack of good technical information out there on the Vauxhall Vivaro, Primastar and traffic van and in particular the rear hub settings.

I recently had a rear hub bearing seize up, luckily the bearing had not welded itself to the stub axle. Which is all too common in this type of bearing failure.


I am surprised and concerned to find a lot of miss information on forums. The lack of this information is making a statement like: “if you don't know the torque setting for the hub nut just tighten it up as tight as you can and then put a scaffold pole on the Tee bar and do it up some more!”. This stratagem can be dangerous and will cause the bearing to prematurely fail again. Why? The rear hub bearing is of the taper roller type which means that if you do not set it up correctly it will bind on the runners causing it to overheat and seize. These are not like ball bearings which can be over tightened (which is not recommended) because there is not the same direct affect.


The specialist kit you need to do this job properly:

36 mm socket


  1. A thirty-six-millimetre socket for the hub nut. Which is three quarter inch drive that you may step down to half inch.
  2. A Tee bar.
  3. An extension bar like a scaffold pole no longer than a meter for loosening only.
  4. A torque wrench that can go up to three hundred Newton meters. Which are not that expensive. Please note that wrench is Six hundred millimetre long (half a meter) This is the optimum length for this weight of tightness.
  5. Spanners and or sockets for the brake calliper mounting bolts of twenty-one millimetres.
300 Newton meter
torque wrench

Destroyed bearing.
Also shows ABS ring.
Be careful not to damage the wheel sensor. The hub nut should be tightened to two hundred and eighty Newton Meters which is surprisingly not that tight - about a quarter of a turn or so after it has been done up normally with a ratchet. The mounting bolts for the calliper cage- one hundred and eighty Newton meters- you should clean the threads with a tap before adding new thread lock and the wheel nuts are one hundred and forty Newton meters and don't forget to put a little bit of lube on the threads.



If you would like to ask any questions or add further to this post, please do.

Related post:   Sticking handbrake.

9 comments:

  1. You mention 36mm socket but picture shows 34mm?

    ReplyDelete
    Replies
    1. Thank you for your comment and pointing out that the picture caption is wrong.
      I wil change it when I have a chance

      Delete
  2. Hi mitch,


    Is there a quick way of checking whether my vivaro is equipped with ABS as I don't know if I need the ABS ring or not.

    Cheers.

    ReplyDelete
    Replies
    1. Yes there should be a cable that runs along the back of the trailing arm to the rear axle.with a yellow connection. which you maybe able to feel with your hand. That then goes to the sensor behind the caliper body. There is a picture of the rear caliper back in post Handbrake fails MOT that shows it. The cable in the picture looks like a pipe that comes down from the weather plate. It is a case of pocking your head under the back of the van with a light to see it.

      I hope this helps.

      Delete
  3. Did you have a step by step for the complete removal and refit for these rear brake discs?

    ReplyDelete
    Replies
    1. Sorry Glynn I am a time served engineer meaning I did it from memory which I know is of no help to you.

      I would have to write one from scratch and then post it. Something I had not thought was needed.

      Delete
  4. Just did mine today. I'm not a mechanic but found it easier than I thought it would be. Firstly I must correct Mitch on the size of the caliper bolts. They are 21mm and not 18mm (well they are on my 05 vivaro) There are four 18mm bolts but they are for the hub assembly and don't need to be removed. Just undo the two 21mm bolts top and bottom of the caliper and tap it away from the disc. Now you can undo the 36mm nut holding the bearing and disc assembly on. You will need a caliper rewind tool to wind the piston back in, in order to get the new pads back in and over the disc.I've heard of people using long nose pliers but you'll be there all night. There are a few kits on the market but I went for the cheaper cube one(Around £10) with various lugs on it, and while it didn't fit at first I filed 2 lugs down and it fitted perfect. Hope this helps guys

    ReplyDelete
    Replies
    1. Thank you Carl for pointing the incorrect bolt size out. It was not my intention to mislead people and apologize for writing the wrong size. I agree about the Caliper return tool makes the job so much faster. I have in the past used a set of very large adjustable spanner and G clamp to get round having the tool but it is slow.

      Delete
    2. I can confirm it is 280Nm it is a job we have done recently.You should change the smash nut when doing this job.

      Delete