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Help with brakes needed - rears lock first!
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Hi all,
Got a bit of a problem. Had to do an emergency stop in traffic today and nearly spun the car around. The rears locked first and the back came right out as the rear was trying to overtake the front. The car is a LX Torana V8 sedan and is fitted with a 9" ford diff (drum brakes) and has HQ disc brakes up front. It's running the standard large brake booster and master cylinder + stock proportioning valve. All components are in A1 condition. Is there any fix that can be done? Can the stock proportioning valve be modified? The car has a valve installed in the rear line which can be adjusted to simply reduce the rear braking pressure but I am not game to change it as I assume that this would not be the same as what a proportioning valve does, which as I understand it is to proportion a higher ratio of braking pressure toward the front brakes from a certain braking pressure onwards. If you can in practice simply reduce the rear pressure could somebody please confirm that this works. I also assume that other have come across this "rear brake locking first" problem when fitting different rear ends and larger back wheels so I'm really looking forward to any replies. Thanks in advance.
Paul E
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OK - 1st off, you jumped on the brakes. That'll do it. I know its hard but try and practice a squeeeeeeze method. I learnt on a drums-all-round car so I know its scary. Also advanced driving courses will teach you the feel of the pedal as it goes hard as
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I'm pretty sure there is a problem. All tyres are OK and good quality. The fuel tank was full and boot had my tools in it too. I did jump on the brakes a bit, but not excessively in my opinion. The back slid out to the right. I verified that I had a probl
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Hi Paul E.
A couple of things to discuss here.
Firstly, you said you had a Ford 9" rear end, do you have Ford rear brakes, as well or have you had the Torana brakes adapted. Ford rear brakes are prone to lock up especially if you still have th
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Thanks for the info Dr Terry. The rear drums are 6 months old (fitted brand new) and the pads friction rating I'm not sure about. The wheel cylinders are the bid ford ones so I'll try and get smaller ones as you've suggested. Cheers,
Paul E
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For what it's worth I agree with Dr Terry. Your rear wheel cylinders are too big and must be reduced to get more pressure into the front calipers. It might be surprising but drum brakes are much better at braking because of the huge area of brake shoe p
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Thanks for the help guys. Got some smaller wheel cylinders from a XU1 fitted on the rear brakes and a new rear brake shoe on the side that was locking up the most. Stops in a straight line now.
Cheers,
Paul E
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> drum brakes are much better at braking because of the huge area of brake shoe pressing inside the brake drum compared to disk brakes which have a tiny little pad in comparison.
Don't forget that braking produces heat and drums expand making bra
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But the fact remains that for the first 2 or 3 applications the drum brakes are better. And cast iron is better than the stainless steel ones.
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Help with brakes needed - rears lock first!
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