Rear brake's

[Rusty]

Can anyone solve this issue for me.

I've just replaced the rear brakes on my RN85 4X2 Hilux and now when I apply the brakes they are badly shuddering. I followed the workshop manual word for word and have replaced the slave cylinders, drums and shoes, and I can't seem to find the fault.

[qkslvr]

what kind of a shudder is it? does it feel like the back end is 'fishing tailing' a little? or is there just general vibration?

[Rusty]

what kind of a shudder is it? does it feel like the back end is 'fishing tailing' a little? or is there just general vibration?

Thanks qkslvr,

It is a general vibration which is felt each turn of the wheel while the brakes are applied. The faster the wheels are turning the greater the shudder. There are no problems with control or the braking effectiveness, except the the grabbing is greater at one point. I have checked the new drums for out of roundness and there are no issues there. The one thing I have noticed is that the shoes are very abravise, but to me that would mean that would mean that they would try to lock-up if anything. I've done this before with other types of cars, but this is the first time with a Toyota.

[qkslvr]

what kind of a shudder is it? does it feel like the back end is 'fishing tailing' a little? or is there just general vibration?

Thanks qkslvr,

It is a general vibration which is felt each turn of the wheel while the brakes are applied. The faster the wheels are turning the greater the shudder. There are no problems with control or the braking effectiveness, except the the grabbing is greater at one point. I have checked the new drums for out of roundness and there are no issues there. The one thing I have noticed is that the shoes are very abravise, but to me that would mean that would mean that they would try to lock-up if anything. I've done this before with other types of cars, but this is the first time with a Toyota.

How did you check for roundness? It only has to be slighly off for there to be a 'tight spot'. also, did you make sure the drum was centered?

[Rusty]

what kind of a shudder is it? does it feel like the back end is 'fishing tailing' a little? or is there just general vibration?

Thanks qkslvr,

It is a general vibration which is felt each turn of the wheel while the brakes are applied. The faster the wheels are turning the greater the shudder. There are no problems with control or the braking effectiveness, except the the grabbing is greater at one point. I have checked the new drums for out of roundness and there are no issues there. The one thing I have noticed is that the shoes are very abravise, but to me that would mean that would mean that they would try to lock-up if anything. I've done this before with other types of cars, but this is the first time with a Toyota.

How did you check for roundness? It only has to be slighly off for there to be a 'tight spot'. also, did you make sure the drum was centered?

Thanks mate. I checked for roundness using the bush way - by placing the shoe into the drum and running it around. I checked the centering first and all is good. I swapped one of my old drums on the drivers side and this only made a tiny bit of difference. I have been told today that there are another set of shoes under a different number which I'm going to try this weekend. The type of system is called the "DUO TYPE".

Please keep coming up with more things to try - thanks, Russ.

[SuperDave]

The drums only have to have a small bump, in the order of hundreds of an inch, to cause a noticeable shudder.

How were the new brakes bedded in? If you put too much heat through them early on there is a chance that they did not bed correctly, machining the surface of the drum might fix that problem. The only other idea I can think of is the pad assembly being a little loose and causing the shudder. But I take it you wouldn't have the second problem if you have done this before.

[Rusty]

The drums only have to have a small bump, in the order of hundreds of an inch, to cause a noticeable shudder.

How were the new brakes bedded in? If you put too much heat through them early on there is a chance that they did not bed correctly, machining the surface of the drum might fix that problem. The only other idea I can think of is the pad assembly being a little loose and causing the shudder. But I take it you wouldn't have the second problem if you have done this before.

Thanks mate. I just found out that the brake shoes that were supplied were the wrong one's when I fitted the new after-market drums. Code 1485 are the replacement shoes when using the original equipment, however when you fit new shoes and new drums you need to fit Code 1371. Apparently there is a .5 mm variance in the shoe width. Supplier appologised for the inconvenience.

In other words Super Dave - your right