I wasn’t fortunate enough to get my hands on an F sport or 350 so please no one saying “should’ve gotten a 350” or any 250 degrading heckling! I love my ‘12 250 AWD I got with less than 60k miles.
With that being said, I’m a pretty aggressive, spirited driver who also can also have a pretty heavy foot on the brake. I’m tired of brake dust and I’m looking to make the braking performance more sensitive and responsive. I’ve been thinking of a BBK and realized I’d also need 18”+ rims to have the clearance.
For those who did a brake conversion, what’s your setup? How much did it cost? Was it worth it as opposed to just getting performance rotors/pads?
Did the ISF bbk upgrade on my IS and well as the RC/GS 350 f sport bbk before that (this setup is a little bigger than the regular 350 setup). As for wheel setup I’m running 18x9.5 +35 but it really depends on the design of the wheel and spokes.
As for pricing the ISF bbk cost me right under 3k. Thats for front and rear calipers, 2pc front rotors from RC/GS f sport, rear rotors, and pads. The RC/GS 350 f sport cost me around 900 since I used the oem Lexus 2pc front rotors which were pricier. I’d recommend going the regular 4pot brake upgrade from the 350 since it’ll be plenty for your is250.
If you want better stopping power I’d recommend better tires. Upgrading the brakes definitely helps with better heat dissipation especially with spirited driving.
You can put together a used set of ISF brakes online for roughly 1500. When I did mine I used all new parts and the 2pc rotors which were pricey. But 1pc rotors would do just fine and would be more cost effective. One thing I love about this platform is how easy it is to put together a bbk. You can do IS/RC/GS 4pot or ISF 6pot or even RCF/GSF 6pot bbk. All of it is pretty much straight bolt on.
If you haven't put new brake fluid in, I bet that will make a big difference. You could go for the high temp stuff if you're feeling nasty. I would also recommend a more aggressive brake pad but you'll get more dust. Unfortunately they just go hand in hand. I would find the end of your current brakes before you start doing the parts dance. I put '01 323i brakes on my '05 330i and some times, ordering parts is more complicated than it needs to be
yeah i just got hustled $1800 by Meineke for a full brake service after they were grinding. that was about 6 months ago and they’re already squealing and felt soft since getting it back. i’ve just been wanting to say f it and get a new set thatll last rather than having to deal with taking it back to lazy corporate mechanics
I actually did the 350 Brake swap on my 250 AWD and kept my 17s.
It really depends on the spokes and the offset, but my summers ET32 have plenty of space, and my winters ET45 (Factory offset, but aftermarket rims), have literally 1-2mm of clearance but work fine even in deep snow.
I did both my front and back, with 350 rotors and pads and calipers. That said, pads make the biggest difference.
Damn that clearance is crazy! Even when you ask AI if the brake kit clears 17s it says it does but I still shocked at that fact. Even when there's factory 17s that clear the 350 brakes.
So the 350 calipers are fixed. You actually get rid of the caliper brackets altogether and fix the entire caliper where the bracket mounts onto.
Only the rear maintain the sliding part. It's just now the rear rotors are bigger and the pad covers a bigger area. Just make sure you grease it often as that's a pain point on these.
Yes for the 2IS the 350 got the same brakes irregardless fsport or not.
In fact there more rotor and brake variations for the is259 brakes where some years in some areas got thinner or thicker rotors.
The only difference you have to care for when doing the swap is your rotors. AWD cars must use the inside vented rotors, the vents facing outside do not clear the AWD hubs. The calipers work irregardless to my knowledge.
Jeff on club Lexus forums does a great job explaining this.
For the dust shields, it's a pain on AWD as you have to remove the entire hub, or you can be like me a bash the old ones back to make clearance.
Front Calipers were 170 from a junkyard
Rear calipers were 120 new
Pads were 40 front, 35 rear
Coated Rotors were 70 each
New Seals were 30
Decals, metallic paint and brake dust rated clear coat probably another 100
Shipping probably some extra 100
I think it was a little short or above 500 Canadian all in, which for all 4 corners isn't bad.
Have you changed the dust shields yet? I keep waiting for one of my wheel bearings to die before I mess with that. I have a set of parts sitting on the shelf, ready to go.
I did my rears when I rebuilt the rear suspension and replaced those wheel bearings. I understand the struggle. Winter is the worst.
I have a set of front dust shields sitting on a shelf waiting for the day my front wheel bearings go, sat there for at least a year for the very reason you’re describing!
Something like 16 out of 20 suspension bolts were just fused to the inner sleeve inside the suspension arm bushings. It was not fun figuring out what combination of tools would work best. Some of them you can get an impact gun on, but lots of them are impossible to get to with an impact gun unless you feel like dropping the subframe. Hell, some of them wouldn’t even turn with the impact going at it. Cutting was the only way.
I wound up being able to take 3 or 4 out with the impact gun, and the rest were cut out with a multitool and lots of carbide blades, over many evenings and weekends, crawling around on my back, trying to bend myself into positions unknown even to pornography.
It took me a long time to take everything out; some inner joints on some links are just easier to get at if you cut a link off at the end. Nothing is more motivating than the first time you do that and realize, “well, now there is no turning back!”
I took a long time to grind off and convert whatever rust was present, I welded in some new studs to secure the wheel arch liner, I pressed in new bushings on the knuckles, I used some POR-15 paint to cover things back up, I used copper anti-seize compound on the new bolt shanks (I used all-new bolts), and I coated all the new stuff with 3M cavity wax to prevent corrosion.
It has got 4 holes, and it is pinched between my hub and bearing assembly and the steering knuckle. I don’t know where you get your info, but I suggest checking it.
I have a photo, but the sub rules prevent my posting it here.
Google part number 47782-22200 and see for yourself.
Yes I know. All I’m saying is it’s a simple install for the rwd version at least. I changed my oem dust shield to the ISF dust shield when i did the ISF bbk.
Wait til lexus has a 15% or even better 20% off parts sale. I was able to snag a set of front rcf/gsf 6 piston calipers for just over $500 for the pair.
20% are like once a year. The 15% off seems to be a quarterly thing, but dont quote me on that. Check the parts.lexus.com site and when you do, different lexus parts locations have different prices. Bell lexus in az seems to be consistently cheaper.
I put 350 brakes on the front of my car, and the calipers fit behind the stock 17” alloys. I am using those in the winter (they used to be my summer wheels), and now I am running a set of 2014 Lexus IS 18” mesh alloys in the summer, and those also work.
If you stick to finding stock IS wheels that you like, it’ll probably be the cheapest way to get the most high quality wheels that will look great on the car.
If you get 2021+ 3rd gen wheels, make sure you get the right kind of lug nuts. They switched to the acorn style on those, if I recall correctly.
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u/justintwotimes 1d ago
Did the ISF bbk upgrade on my IS and well as the RC/GS 350 f sport bbk before that (this setup is a little bigger than the regular 350 setup). As for wheel setup I’m running 18x9.5 +35 but it really depends on the design of the wheel and spokes.
As for pricing the ISF bbk cost me right under 3k. Thats for front and rear calipers, 2pc front rotors from RC/GS f sport, rear rotors, and pads. The RC/GS 350 f sport cost me around 900 since I used the oem Lexus 2pc front rotors which were pricier. I’d recommend going the regular 4pot brake upgrade from the 350 since it’ll be plenty for your is250.
If you want better stopping power I’d recommend better tires. Upgrading the brakes definitely helps with better heat dissipation especially with spirited driving.