rear brakes "grabbing"

a mate of mine has a acco 510a (i sold it to him earlier this year) he has just passed the truck for rego so now hes happy .... however the rear brakes are grabbing & overheating,he says he can back the adjusters off and the truck will roll freely ,then as he starts to drive they will shortly start to grab again .. any ideas? im thinking a faulty rear proportioning valve(if fitted) or a faulty brake booster

I have same problem but my one comes when the drums get cold and my is caused by a leaking axle seal it's ok in the warm weather but lousy in the winter. Dave

OK
Wot sorta brakes we talk n about
Hyd, Vac Hyd, Air Hyd, Air 'S' cams, Air wedge ??

any oil n grease on linings will cause m to grab

the xperts tell us the correct n only way to fix is to put new clean linings and thorougly clean all oil n grease from brake drum
n keep u're grubby little hands off the lining n brake drum surface

but wot u can do
is wash linings and brake drum in petrol etc donot submerge in petrol
then in a safe place with petrol or any other flamerables out of danger
apply a little warm with gas ax (oxy Aceterlene) to the linings to bring out all the oil n grease
this above procedure can work but is not recommended for a truck th@ is full on in carting to the max as a daily grind

ButEyeDoSt&2BCorrected

WotSayU

LOL
cya

Swishy is probably correct but there may be another reason for this. I had some of the first non asbestos shoes fitted to a truck I owned once. You set the adjustment cold, so they were just clear of the drum but when hot the shoes expanded more than the drum and started to drag badly. The only way to do it was to set the adjustment with warm brakes but then they didnt work too well when cold.

so far my mate has removed the rear drums (again)at this stage he thinks the linings are oversized..he has the adjusters backed off all the way .. ill keep everyone informed of his progress