Lobex

5 hours ago, Linas.P said:

They would be identical, however my personal opinion - it would be waste of money.

First of all you would need new discs anyway when you upgrade your calipers to ones from IS350, so you get the discs now and then throw them away. Secondly, only replacing discs makes no measurable difference - I have fitted sort of "performance" drilled discs and apart from generating more noise, wearing quicker, cracking and warping there were no noticeable benefit in stopping power.

I am going to get mine skimmed soon in a hope of getting the back to the shape as they still have a lot of thickness left, but I would not advise getting anything but most generic discs on IS250. The only advantage I had was that they were coated with protective coating, so I have no issue of rusted ventilation channels or the surface which touches the hubs like on the original discs.  Basically, the reason why I was replacing old discs were that they were rusted, ventilation channels blocked by rust flakes and they weren't sitting flush on hubs. Obviously, I could have the rust cleaned on the discs, but I just asked to clean the hubs and ordered new discs.

Better invest in better pads... and if you do order discs make sure if you have ventilated or solid rears as there are difference year to year. Some IS250 have solid some vented discs and it is not trim dependent. I believe it depends on the actual manufacturing date of the car and not even date of registration. Effectively, some cars registered before 2008 have solid rear discs, but some already have ventilated, whereas all the cars after ~ 2008 have only ventilated.  

👍

On 1. 3. 2018 at 7:19 PM, Linas.P said:

Yes, that seems to be the case - only calipers, discs and pads obviously. I believe rear dust shields won't fit IS250 hubs, so you will have to do without them.

Linas.P, thanks a million!! Let me ask you one more thing. I decided to buy just the performance disks for the 250 for now, and than after I have bought the 18" wheels I will upgrade the brakes to 350s. I found them on Carid but I am not sure if the American Lexus IS 250 identical to the Japanese one, regarding the brakes ofcourse?  Thanks

On 20. 2. 2018 at 9:21 PM, Linas.P said:

I really don't know. If anything I would just upgrade the wheel to 18" ... just in case rather than caring about geometry of the car later.. Previously I just wrongly assumed that the bolt-on upgrade includes hubs, but upon reading the thread again it is clear hub change would impact much more than just a brake calipers fitting. 

Is there any reason why you want  to stay with 17"?

 

I was actually thinking of going on 18" for the summer tire but keep the 17" for the winter because it's much easier to get the tires.  But I guess I'll be driving 18" the whole year round and wory about the tires when it comes to that. And you say that with 18" I can do the 350 upgrade without changing the hubs or anything else?

On 30. 1. 2018 at 7:57 PM, Linas.P said:

Not sure where hub theory came into my mind... probably memory issue... from the past I have looked to thread below and could swear the guy replaced hubs, but reading it again - no mention of the hubs:

https://www.clublexus.com/forums/suspension-and-brakes/405811-is350-brake-upgrade-on-is250.html

So if I change the hub too the 17" original wheels will clear? Do you know anything about the steering knuckles. Do they have to be replaced also? Thanks.. 

On 7. 2. 2018 at 8:46 PM, Lobex said:

So the original 17" won't clear?

Sorry I quoted wrong. What I meant to ask you was if I change the hub will the original 17"  clear or not? And do I need to change the steering knuckles also or are they the same? Thanks 

On 20. 1. 2018 at 12:57 PM, Exdee said:

The hub on the IS350 is different. Unless you are going to replace the hub too the stock 17" wheels won't clear. 

The clearance is fine as far as the diameter goes but offset is an issue. 17 wheels with a more aggressive offset will clear.

And I know all of this as I too found the brakes on the IS250 inadequate!

So the original 17" won't clear?

On 29. 1. 2018 at 6:58 PM, Tango said:

I don't know if a hub conversion is even possible without knowledge of the full front suspension set-up. Here's a few pics of the calipers as received, another when deciding whether to paint them all black or black with polished face and the car with the new discs and calipers. The pads were Hawk ceramic which provided excellent progressive braking with very little dusting, unlike the high dust grabby standard set-up. The car was on Eibach American specification lowering springs with 1.5 inch drop on the front and 1 inch drop on the rear. Having a drop of more than 30mm on the front required the fitting of a camber kit to bring the geometry back within the Lexus specified tolerances.

What about the steering knuckles, do I have to replace them also or just the hubs? I'm asking because the caliper fixes to the knuckle and if the holes don't match than I have a new problem.. If it's just the hubs and if they are really that cheap (https://www.rockauto.com/en/catalog/lexus,2007,is350,3.5l+v6,1434544,brake+&+wheel+hub,wheel+bearing+&+hub+assembly,1636) than it's a nobrainer, I'm definitely doing it. And the 17" will definitely clear the 350s rotors and calipers?

Hm, I guess I'll be staying on standard dimensions. Thanks for the info Tango, not even my mechanic knew of this diference.  

But I would still like to get a 4 piston front caliper if its possible . Does anyone have any suggestions? 

On 23. 1. 2018 at 8:04 PM, Linas.P said:

Just because they are standard 17" for mk2 - my car used to have set of these wheels originally, there are no way to get it wrong. Pre-face lift cars had two options:

18":

17":

Again, it seems (apparently) 17" clears IS350 brakes - I personally would go for 18" regardless... just in case - it looks tight with 17".

I was actually thinking about 18" for the summer tire but I would still like to keep the 17" for the winter because it's easier to get the tires. I also asked my mechanic for any sugestions and than i'll decide.  Thanks for all the info 👍

On 18. 1. 2018 at 8:18 PM, Linas.P said:

I am very surprised by that, I remember reading on US forum that it won't clear front caliper. Additionally, it seems that all US 350's had 18inch alloys from factory. However, if following car is anything to go by (JDM version):

https://www.beforward.jp/lexus/is/bf708762/id/836297/

..then indeed 17 inch clears IS350 brakes (it looks quite thigh there). Note that rear ones looks identical to IS250, so maybe you only need to get front's done.

How do you know they are 17s? I can't find any data..

On 17. 1. 2018 at 9:33 AM, TigerFish said:

I’d say it was a good move. Regardless of the adequacy of the stock brakes, if you don’t have 100% confidence in them when they are pushed hard (I never did on any of my GS’s), then it is worth the work. Even if yours aren’t right in some way, fixing the stock ones, or going for a much better option, is a no brainier IMO. Especially as we all know, the sliding calipers are commonly “problematic” on most lexus models.

Unfortunately, I’ve no idea how easily they fit, but it sounds like it has been done before, and the other lexus models that have those calipers as stock, run 17’s as an option.


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Thanks 👍

On 20. 1. 2018 at 2:53 PM, Linas.P said:

This is incorrect, IS250 F-Sport has identical brakes to the rest of the range. Specifically, in UK there seems to be only styling differences, half-alcantara seats and sound-amplifying intake, but mechanically the car is identical to the rest. EU and US models seems to have upgraded anti-roll bars, but as far as suspension and brakes goes they are still identical.

@Exdee - that was my understanding as well, but as posted above JDM car has stock 17 inch alloys over IS350 brakes... That is new to me as well... 

Funny, cause I got this info about the F sport from a friend that works at a Lexus dealer here in Slovenia. But its also true that Lexus dealers in Slovenia don't know sh..t about the brand.  They still think Audi is the best car in the world.. Anyway thanks for all the info.. Regards,

Iztok 

On 17. 1. 2018 at 12:06 AM, Rebecca said:

Do they? 

I never noticed this in my 250 f-sport and 75% of my driving takes place across the very twisty roads of the Brecon beacons/black mountains. 

I consider myself an enthusiastic driver and found the brakes of the 250 to be superb in any situation. 

Sure you can fit the larger brakes if you wish but you won't see any benefit with the upgrade. 

Of course they will look better on the vehicle I guess.

If you are talking about the 250 F sport you must know that it already comes with bigger brakes and an upgraded suspension as stock..

The other thing is that I when I raced rally cars I got used to braking in the middle of the corner with my left food which I still do today so the brakes really do a lot of work..

I don't know how the roads in Black mountains look like but the roads here in Slovenia are "sick" 😀

17 hours ago, Linas.P said:

IS350 calipers are one of typical IS250 upgrades. However, the front calipers won't clear 17" wheels - you have to go 18" if you want IS350 calipers. 

One way or another I highly recommend to do this, it is massive benefit from having IS350 brakes in terms of maintenance. IS250 calipers is really weak spot of the car, they are definitely undersized and wears excessively. I even hardly lock-up the wheels - I remember when I fitted new tires and had nice 500 miles run-in there was the point where it would not engage ABS, because wheels would not slip. Obviously, that heavily depends on conditions - yes on the wet road or with the worn tires IS250 calipers can lock-up wheels.

That all said, the biggest benefit of IS350 calipers is the maintenance, wear on IS250 is excessive - disks needs changing with almost every set of pads. As well undersized disk on IS250 are easily overheated, easy to warp and crack - especially if you fit some aftermarket drilled/grooved/slotted ones. And lets not start talking about all calipers sticking issues etc. - that is the sole pain point of mk IS250 (maybe expect of creaks from dash).

Whats more - you will be better of looking for GS350/300 mk2 calipers, they are identical to IS350 mk2 but being from older car are much cheaper.

Are you sure I have to go to 18' because I checked the factory wheel size and and the IS 350 also comes on 17' so I should be OK..

Don't get me wrong the brakes work perfectly in normal everyday driving. But when you are driving fast on a twisti road they overheat very quickly. That's why the upgrade..

Hi,

I have a 2007 IS 250 II aut and I think that the original brakes are really not up to the job so I was thinking about upgrading them. Maybe put on the is350s 4 piston caliper and an original size drilled/slotted rotor because I would like to stay on the 17" tires. 

What do you think? Will the 350s caliper fit the original size rotor and a 17" wheel? Have any other suggestions?

Thanks..

On 26. 11. 2017 at 5:51 PM, is200 Newbie said:

I had a similar issue - had the oil changed and although it felt better I still had the vibration.

I found out through trial and error and from what owners on the forum were saying than there was an issue with the wheels. I found out the inner alloy was corroding on one wheel (had the tyre removed on the off chance) Found the corrosion was separating the tyre from the rim. I guessed all would be the same as they were not good at holding pressures.

Wheels have been changed and issue has gone. Not stating this is your issue but sounds similar so if you are able to change the wheels to do a trial then I would give that a go.

First thing monday I called the garage were I had my gearbox serviced and they told that it's normal for the shaking to continue for a short time before the program learns my driving after program reset. And after 3 days it really stoped and it hasn't been shaking since than. Looks like we have fixed the problem. 

Thanks for all you help,

Iztok 

Correct me if I am wrong but if the gear is damaged wouldn't it shake always when the car is in that gear? Because as  I said it doesn't happen always just from time to time. It feels like the transmission is engageing and disengaging in a very short interval.  Could it be something that isn't connected to the transmission.  Could it be the diferential? 

Hi, I have a problem with my 2007 Is 250 automatic transmission.  When I accelerate slowly the car starts shaking like if you would be driving over small bumps. It usually starts at arround 50 km/h but goes away when I continue accelerating. But it doesn't hapen all the time!? I had the transmission cleaned put in new oil and reset the transmission memory but it's still shaking. What do you think is the problem?  Thanks, Iztok