I think I need new brakes. So might as well upgrade. Could use some advice please. :)

[Lex_utor]

I have an IS250. My car is pulling to the sides when I brake. It doesn't pull to just one side. It depends on the road I guess. But it pulls heavily to either side. Also squeaks and or I hear the brakes. But the wheels are not hot, so I guess the calipers are not seized. I have 19" 8.5 J wheels all around. Front tires are 225/35.  The discs are lipped. So I guess I need new discs and maybe new pads. So I thought about upgrading to GS350 front calipers and ventilated slotted discs all around. I found Rotinger, which came well recommended. Anybody ever used them? Thinking of going with their graphite line.

So for the front I will go GS350 calipers with larger discs. The stock IS250 front discs are 296mm right? How thick? 28mm? Mine are ventilated.

Rear discs I also want to go larger. Stock is 291mm? But I would like to keep the stock calipers for the rear. Is that a problem? I did some research and it seems since I have non ventilated discs at the rear, my discs are 10mm thick, while the ventilated would be 18mm. I found a Rotinger 291mm rear disc and they are also 10mm. Meaning they would fit my stock rear caliper. But they are ventilated. In a 10mm disc, I was wondering, not too thin for ventilated? But I guess it must be 10mm thick or it won't fit my stock rear calipers. And if 291mm is the same as stock size, I would like larger ones. Just not sure it's possible to go larger while using the stock rear calipers. I just thought if I'm going to get new discs, might as well get larger ones as the stock ones look a little small in my 19" wheels.

 

Thanks as always for the advice. 🙂

[H3XME]

13 hours ago, Lex_utor said:

I have an IS250. My car is pulling to the sides when I brake. It doesn't pull to just one side. It depends on the road I guess. But it pulls heavily to either side. Also squeaks and or I hear the brakes. But the wheels are not hot, so I guess the calipers are not seized. I have 19" 8.5 J wheels all around. Front tires are 225/35.  The discs are lipped. So I guess I need new discs and maybe new pads. So I thought about upgrading to GS350 front calipers and ventilated slotted discs all around. I found Rotinger, which came well recommended. Anybody ever used them? Thinking of going with their graphite line.

So for the front I will go GS350 calipers with larger discs. The stock IS250 front discs are 296mm right? How thick? 28mm? Mine are ventilated.

Rear discs I also want to go larger. Stock is 291mm? But I would like to keep the stock calipers for the rear. Is that a problem? I did some research and it seems since I have non ventilated discs at the rear, my discs are 10mm thick, while the ventilated would be 18mm. I found a Rotinger 291mm rear disc and they are also 10mm. Meaning they would fit my stock rear caliper. But they are ventilated. In a 10mm disc, I was wondering, not too thin for ventilated? But I guess it must be 10mm thick or it won't fit my stock rear calipers. And if 291mm is the same as stock size, I would like larger ones. Just not sure it's possible to go larger while using the stock rear calipers. I just thought if I'm going to get new discs, might as well get larger ones as the stock ones look a little small in my 19" wheels.

 

Thanks as always for the advice. 🙂

If they are lipped and squeak, you definitely new brake pads. Maybe even discs.. They might be warped if it's pulling or maybe the braking power isn't being distributed evenly. I'd give the calipers an overhaul, grease up the slider pins just in case and get new pads/discs. Brake fluid flush would be beneficial too..

As for bigger brakes, I was toying with the idea of doing the fronts on my IS250 as well. 2005+ GS300/350 GS450h use the same calipers and discs IIRC. Find whatever is cheapest (eBay / scrapyard) and get it refurbed - can even pick your desired colour then 😉

And the rears... I doubt yours would be 291mm as mine are 310mm x 18mm vented rears. I believe only 220d and possibly the BASIC spec is250 had the smaller brakes. This is why I wouldn't bother putting GS brakes on the back. 90% of the braking is happening on the front anyway, that's the real gain. 

[Lex_utor]

1 hour ago, H3XME said:

If they are lipped and squeak, you definitely new brake pads. Maybe even discs.. They might be warped if it's pulling or maybe the braking power isn't being distributed evenly. I'd give the calipers an overhaul, grease up the slider pins just in case and get new pads/discs. Brake fluid flush would be beneficial too..

As for bigger brakes, I was toying with the idea of doing the fronts on my IS250 as well. 2005+ GS300/350 GS450h use the same calipers and discs IIRC. Find whatever is cheapest (eBay / scrapyard) and get it refurbed - can even pick your desired colour then 😉

And the rears... I doubt yours would be 291mm as mine are 310mm x 18mm vented rears. I believe only 220d and possibly the BASIC spec is250 had the smaller brakes. This is why I wouldn't bother putting GS brakes on the back. 90% of the braking is happening on the front anyway, that's the real gain. 

Thanks for the reply.

My rear brake discs are much smaller than my front ones. If my rear discs are 310mm, I wonder how big are my front discs. But my rear discs are not ventilated. I read the solid not ventilated rear discs are 10mm thick. So I was guessing I had 291mm x 10mm rear and 310mm front as the front ones are ventilated.

 

About the pulling, what you said makes a lot of sense. In any case I have decided to change the discs and calipers on the front to GS ones as well as pads.  So hopefully this will solve the pulling problem.

 

For the rear, as you said, doesn't seem to be worth it putting GS brakes on the rear. But I would like to at least get larger discs for the rear. If I will have to buy new ones anyways because they are worn. But I don't want to replace the rear calipers at all. I'm just not sure if it's possible to get larger discs for the current rear calipers, or if to get larger discs I have to also upgrade the calipers.

[H3XME]

2 minutes ago, Lex_utor said:

Thanks for the reply.

My rear brake discs are much smaller than my front ones. If my rear discs are 310mm, I wonder how big are my front discs. But my rear discs are not ventilated. I read the solid not ventilated rear discs are 10mm thick. So I was guessing I had 291mm x 10mm rear and 310mm front as the front ones are ventilated.

 

About the pulling, what you said makes a lot of sense. In any case I have decided to change the discs and calipers on the front to GS ones as well as pads.  So hopefully this will solve the pulling problem.

 

For the rear, as you said, doesn't seem to be worth it putting GS brakes on the rear. But I would like to at least get larger discs for the rear. If I will have to buy new ones anyways because they are worn. But I don't want to replace the rear calipers at all. I'm just not sure if it's possible to get larger discs for the current rear calipers, or if to get larger discs I have to also upgrade the calipers.

Interesting. Must be some NON-UK low spec thing. I don't know if my rear calipers would be the same as your calipers then since my rear discs are 310 vented. (bigger than front) - BMWs do this a lot, they have rear discs bigger than front, but it might be something to do with hand brake mechanism - even though mine is a manual with a normal hand brake as opposed to electric foot brake on auto's.

[Lex_utor]

22 minutes ago, H3XME said:

Interesting. Must be some NON-UK low spec thing. I don't know if my rear calipers would be the same as your calipers then since my rear discs are 310 vented. (bigger than front) - BMWs do this a lot, they have rear discs bigger than front, but it might be something to do with hand brake mechanism - even though mine is a manual with a normal hand brake as opposed to electric foot brake on auto's.

Could be that a former owner cheaped out when replacing the rear discs. But I just looked and my rear calipers say L10, which I think means 10mm thick. 

[J Henderson]

6 hours ago, Lex_utor said:

But I just looked and my rear calipers say L10, which I think means 10mm thick. 

Correct. The vented calipers are different and have 18 stamped on them, so you would need to upgrade the calipers too.

As for your issue with the steering pulling. That could be down to the tyres, not the brakes.

My own car tramlined quite badly when I had 19" wheels on it.

[H3XME]

28 minutes ago, J Henderson said:

As for your issue with the steering pulling. That could be down to the tyres, not the brakes.

My own car tramlined quite badly when I had 19" wheels on it.

It wouldn't be happening under braking. 

And wheel diameter wouldn't make a difference. Unbalanced wheels or uneven pressures more like

[Lex_utor]

On 10/4/2021 at 9:00 PM, J Henderson said:

Correct. The vented calipers are different and have 18 stamped on them, so you would need to upgrade the calipers too.

As for your issue with the steering pulling. That could be down to the tyres, not the brakes.

My own car tramlined quite badly when I had 19" wheels on it.

I first thought it was because of the 19" wheels as well. But it doesn't pull unless braking. I can let go from the steering wheel when driving and it doesn't pull to any side. Once I looked at the discs and saw how lipped they are, I started thinking it was probably the brakes. I think they might be the original discs.

About the rear discs, so the only way to get larger discs is upgrading the calipers as well? There is no aftermarket 10mm discs which are a bit larger? The current discs look pretty comical in the 19" wheels.  I wouldn't bother changing if they didn't need replacement. But since I must buy new ones anyway, I thought I might as well make it look nicer too in the process. 🙂

 

[Lex_utor]

On 10/4/2021 at 9:29 PM, H3XME said:

It wouldn't be happening under braking. 

And wheel diameter wouldn't make a difference. Unbalanced wheels or uneven pressures more like

I think it has to be the brakes right? If the wheels were unbalanced it would pull in normal driving too and not just under braking I would say?

[jumbojake]

I get the same on my IS200d ..... seems to be very sensitive to the road surface and camber... it's always been like it, even before/after both front and rear brake changes.