Have done approx 78,000m from new in 2001MY 115PS TDI PD. My driving style is very light on brake use, plus main jouney is m/way. Original pads and discs stll have plenty of meat left. Rear brake squeal occasionally evident over approx last 30,000m.
Today I had the OSR tyre renewed... The operator managed to damage the alloy wheel by incorrectly loacting it on the tyre removing machine - wheel now has deep gouges across two of the spokes. I didnt notice this until I got home, but what I did notice on the way home was worse than expected fuel economy on the Multi function display, and really bad squealling from the rear brakes, which was partly silenced by sharp application of h/brake while in forward motion.
I've had the wheel off, cant see anythng wrong, except excessive binding. The binding is severe when the wheel bolts are torqued to spec (89 ft lbs), but less severe when bolts just finger tight. Torque to turn wheel is in region of 35 ft lbs in severe case.
After road test of 10 miles, NSR disc temp 50 deg C. OSR disc temp 158 deg C. Clearly I need to fix this - any suggestions?
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I would check:
1) if the handbrake is releasing properly, you can loosen it at the handbrake to confirm, if no difference reset the adjuster to how it was.
2) more likely though is the caliper sticking, from the symptons you describe the caliper guide mechanism could be seized so with the wheelnuts fully torqued the inner pad is in contact with the disc and is binding, and with the wheelnuts loosened the binding is less. Or possibly could be the piston sticking. Either way you need to release the handbrake cable and remove the pads, clean the caliper/piston with brake cleaner, check and lubricate the guide/slider mechanism and put it all back together with the coppergrease in the usual areas, set the pad to disc clearance (if it the same arrangement as Mk2 Golf GTi's!) and set the handbrake, should do the trick.
Ian
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Thanks Ian, missed you post by mins.
It was indeed the pads siezed in the caliper brkt. I've removed all the gung which was preventing their movement, and applied Never Seez (a nickel paste high temperature past to the relevant areas. Everything else was OK.
The difference is amazing. The car rolls much more freely than it did before the tyre change.
As the handbrake adjustment was OK I can only assume something got disturbed in the tyre change process.
The caliper bolts have pre-applied Loctite compound so I assume this is the reason for renewal. Strangely, the local main VW dealer does not stock these....
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PS
Will be dismantling caliper later today, but read in Haynes manual that caliper bracket retaining bolts must be renewed.
Is this really necessary? - the torque spec does not suggest they are put into yield.
(Thinking about it overnight, I think the handbrake mech has been "tweaked" somehow, moving the inboard pad closer to the disc, which may be why binding force increases when the wheel bolts are tightened).
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PS Will be dismantling caliper later today, but read in Haynes manual that caliper bracket retaining bolts must be renewed. Is this really necessary? - the torque spec does not suggest they are put into yield.
You're correct. But they only cost pennies so I generally renew them as a matter of course. Dealers never seem to stock them so I can only assume that their own factory trained technicians don't bother - maybe just drop a blob of Loctite on the old ones?
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