Toyota warranty - brake disc replacement

Grey_Critic

Warranty covers a *faulty* part so in theory as only one disc was corroded then just replacing that one is correct.

marlot

If they're replacing the disc like-for-like, I'd be surprised if there was an issue given the modest mileage on the other one.

Give the new pads a few hundred miles to settle in, then try hard braking from (say) 50mph.  I'd expect the car to pull up evenly.

roddydogs

If you were paying, it would be a different story!

inspectorperez

You mention that your car is 11 months old. Presumably by that you mean you have owned it for 11 months?

If so, I wonder when the car was manufactured? It does sound perhaps that your vehicle may have been sitting somewhere for a long time before it was delivered to the dealer.

I once had such an issue with a Renault Megane which I discovered had been sitting in a field for months after unloaded from cargo boat. The only issue with that vehicle was corroded brake discs which were replaced under warranty along with new pads.

collins74

I think if I was paying it would be replace as a pair and they would never recommend anything else 😂.

We couldn’t pick the car up for three weeks due to Covid and it may well have been stored somewhere for a while.

We will give time for the brakes to bed in and then so how they are.

Username03725

5800 miles in 11 months is buttons really, you've barely run it in. In this specific situation there's no issue with replacing just one disc. Normally they would be replaced in pairs but normally replacement is due to wear; in this case it isn't so - assuming the good disc didn't have any significant corrosion - there's no issue with it. As above, brake systems automatically apply equal pressure anyway so even allowing for the small difference in disc thickness it won't have any effect on braking performance. 

Try it yourself - find a quiet empty space and brake with varying degrees of harshness and see if you can identify any pulling one side or the other. That's all that matters in this instance. Pretty certain that you won't. 

Username03725

collins74 said:

I think if I was paying it would be replace as a pair and they would never recommend anything else 😂.

We couldn’t pick the car up for three weeks due to Covid and it may well have been stored somewhere for a while.

We will give time for the brakes to bed in and then so how they are.

You'd do well occasionally to brake a little more firmly than normal tbh. In the same way that an Italian tune-up is good for an engine occasionally to clear the cobwebs out, brakes do suffer from light surface rust after even a rainy day, and it's worth braking firmly enough to clear that front and rear surface rust from time to time, having ensured the obvious that there's no one up your trumpet when do you do it etc.

peter12345678910

It normally is the same pressure on either side. But my last mot I had a brake imbalance with the rear wheels. So after I changed the wheel bearing, I did a simple test, i raised the wheel and pushed it, obviously one wheel turned over twice and the other did not turn much.

It was very easy to adjust rear drum brakes. But you check the front wheels in the same way.. I am guessing but I am no mechanic not even close to one, instead of trying to change a perfectly working disc. Jack up each front wheel and try to spin it, this is will tell you if there is a brake imbalance. But I am just guessing. 

marlot

peter12345678910 said:

It normally is the same pressure on either side. But my last mot I had a brake imbalance with the rear wheels. So after I changed the wheel bearing, I did a simple test, i raised the wheel and pushed it, obviously one wheel turned over twice and the other did not turn much.

It was very easy to adjust rear drum brakes. But you check the front wheels in the same way.. I am guessing but I am no mechanic not even close to one, instead of trying to change a perfectly working disc. Jack up each front wheel and try to spin it, this is will tell you if there is a brake imbalance. But I am just guessing. 

Drum brakes have an adjuster, which alters the distance the shoes are from the drum, and hence the balance.

Disc brakes do not.  There is nothing to adjust.

Richard53

peter12345678910 said:

It was very easy to adjust rear drum brakes. But you check the front wheels in the same way.. I am guessing but I am no mechanic not even close to one, instead of trying to change a perfectly working disc. Jack up each front wheel and try to spin it, this is will tell you if there is a brake imbalance. But I am just guessing. 

Yes. you are just guessing.   Spinning the front wheels with the car jacked up will tell you nothing about brake imbalance. It'll tell you if the brakes are binding, but that's not the same thing. Brake imbalance is usually caused by sticking calipers where one side is prevented from applying full braking pressure because the brake pistons are corroded in the bores. Cure is new calipers (main dealer £££) or a good clean-up and a seal kit (DIY £).

As others have said, if the opposite disc is not worn, there is no reason to replace both discs. I would, as a DIYer, but I'm fussy. I wouldn't expect a dealer to do so if I were not paying for it. At this mileage, I'd be surprised if there were any significant wear on the other disc. A firm brake test on a quiet road will tell you if you have a problem.