tr4 Disc? judder

[monty]

Decided on a run out the other day. The car, although in my garage, was a little effort to reverse, due to the pad(s) sticking to the disc(s) after an earlier wash. I reversed with a little resistance followed by a clunk. Result, a juddering of steering wheel, front brakes & a faint noise on braking. Obviously a link as it was OK before the wash! Disc now warped or high spot on it or calliper/piston problem? Suggestions?

An engineer friend has offered to skim the discs or should I replace?

Cheers.

[Motorsport Mickey]

Take the wheel off and tighten up the centre stub axle nut removing all play in the taper bearing, no need to "gorilla" it just remove the play. Then measure the disc run out with a magnetic stand or other method of holding a DTI (clock) before jumping to conclusions of warped discs, if so measure the thickness of disc to establish if there is a skim amount left on them.

PS. Push the boat out and check both the front and rear surfaces.

 

Mick Richards

[oldtuckunder]

An engineer friend has offered to skim the discs or should I replace?

 

 

Do as Mick said and take a look you may also spot the problem. If they are standard solid rotors and there i something wrong just junk them, new ones are cheap and most are good (even the cheapest).

 

Alan

[monty]

Take the wheel off and tighten up the centre stub axle nut removing all play in the taper bearing, no need to "gorilla" it just remove the play. Then measure the disc run out with a magnetic stand or other method of holding a DTI (clock) before jumping to conclusions of warped discs, if so measure the thickness of disc to establish if there is a skim amount left on them.

PS. Push the boat out and check both the front and rear surfaces.

 

Mick Richards

Thanks for that Mick, curious to know why I would suddenly get play in the taper bearing by just breaking a temporary 'seal' between disc & pad by reversing. Absolutely no play by 'rocking' the wheels in the usual manner, either before or now.

Regards.

[Peter Cobbold]

Rusty patch still on the disc(s)? - can be removed by driving. Can't myself see a bit of rust warping a disc. Peter

[peejay4A]

I'd guess that some of the pad material has detached and stuck to the discs. I've had exactly that on my old Jag but they were frozen on whilst sat parked at BHX. Getting the car moving shears off a layer of pad and you get your symptoms.

Edited February 16, 2016 by peejay4A

[Motorsport Mickey]

"why I would suddenly get play in the taper bearing by just breaking a temporary 'seal' between disc & pad by reversing"

 

You don't know you do have play, that's why you are going to check it. You also say there is no play when rocking the wheels before or after ? they are taper bearings there should be an amount of play that's why I'm suggesting tightening the stub axle nut to remove it.

Investigate with care, sometimes you can't second guess the cause without doing the necessary work, you have to "earn" the right to diagnose.

 

Mick Richards

[ctc77965o]

I dont think you'll make it worse by driving it...I would bet that a few hard stops will clean things up and all will be fine...root cause is rusty disks...a normal storage issue.