Brembo 380 mm GT kit - install tips (not a full DIY)

[swamp2]

Today I installed the yellow 380 mm GT (Gran Turismo) kit I picked up very lightly used. Sorry guys, no full DIY, nor pics (yet) just a few tips for anyone handy enough to bother with this job in the first place.

1. Jacking: I went rears then fronts. Block the front wheels. Jack on the rear differential (NOT THE ALUMINUM housing) in front of the housing - it is the cast iron/steel metal housing of the differential. You can also use the large flat part of the black painted rear subframe. You should use a 2x4 or wood block for both locations unless you jack has a very firm/thick pad already on it. Once jacked up use two jack stands under the side skirts with appropriate blocks (I just have some custom cut 2x4 pieces I always keep in my trunk). Then you can do both rear wheels. For the front block your right rear wheel and use the e-brake then use the front left jack pad just behind the side skirt. When you lift high enough even the right rear wheel will lift. Then get a single jack stand under the jack point visible right between the front wheels along the cars center line. Now when you release the jack you will have both front wheels elevated so you can do both at the same time. Don't forget to loosen your lug bolts to a low torque value before jacking.
2. Reduce the mess: Lock the brake pedal in the partially depressed position before disconnecting any brake lines. Put a stick between the front seat and the pedal (protect the seat with a towel) and run the seat forward far enough to apply the brakes. Then release the pressure in the calipers by opening and closing the bleed screws (use your catch bottle). This procedure blocks the duct from the brake fluid reservoir to the master cylinder, so when you disconnect the caliper hoses, they hardly drip at all. So long as the pedal remains depressed, brake fluid can't drain down from the reservoir and make a mess.
3. The "right order". Despite any instruction sheets do not disconnect the existing fluid lines until you have the new rotor and caliper fully in place. Then you can minimize fluid spill. Brake fluid is extremely corrosive to almost anything painted. Clean up well and use some brake cleaner (paint safe), simple green, degreaser, etc.
4. You can move the steering rack back and forth (holding the disc) to get better access for loosening bolts, retorqing, running lines, etc.
5. Slide OEM caliper off of disc: You must retract the pistons a bit because of the the ridge naturally created by disc wear. Pop off the anti-vibration clips with a screw driver (they shoot off - cover the area with a gloved hand). Finally use a large C clamp (it does need to be a pretty darn big one...) over the outer pad and back body of the caliper. This will gently retract the pistons making more space between the pads. Don't forget that you can't get the rear rotors off with the ebrake applied.
6. Seized rotor(s)?: Try some penetrating oil. I used Blaster brand penetrating catalyst. It worked wonders - really penetrated far. Add it around the hub to disc connection and in the lug bolt and disc mounting screw bolt holes since it can also penetrate through to the hub in those holes. Let it sit for a while. Then use a dead blow hammer (better than a rubber mallet) on both the front and back faces of the disc. Finally you can buy or rent a disc puller from many auto parts stores. Unfortunately I needed one. Despite the good So Cal weather and roads I still managed some good corrosion. Clean up the corrosion on the hub with a small wire wheel in a battery powered driver. Clean the lug bolt threads and threaded disc mounting holes with brake cleaner (torque specs are for clean/dry threads ONLY) and use a nice coat of copper based anti-seize paste on all of the hubs to prevent another seizure.
7. Trimming splash guards: For the 380mm kit you have to trim both the front and rear splash guards. I've heard these called "dust guards" but my understanding is in fact they are splash guards and improve panic braking in wet condition by keeping the rotor drier. If you choose to simply remove the guards you can easily remove the fronts but to get the rears off requires disassembling the parking brake and even removing the hub. Way too much work for me - trimming seemed like a much better option all around. The fronts are only a few quick snips so the caliper/caliper mount can fit. How to mark them: Remove the OEM rotor and caliper leaving the OEM fluid lines connected. You can rest the OEM caliper on a small can while you work so it does not hang on its fluid line. Hold the new assembled caliper/caliper mount in place and mark your cuts with a sharpie. The rears must have an entire lip/ring that arches up and around the OEM rotor cut off. In other words you actually need more lateral clearance for the larger disc (even if it was not larger in diameter its offset is different and you would still need to trim). It is a bit of work with snips especially to keep a nice curved snip path all the way around the guard. I ended up removing about half of the depth of this lip and I had plenty of clearance. I cleaned up the cuts with a dremel (coarse sanding wheel) and coarse carbide sandpaper. I suppose I could have repainted the exposed metal here but I just could not bring myself to do all of the masking that would be required...
8. Orientation: Discs and rotors are specific to front and rear and left to right. Disc should be mounted such that when looking at the top of any disc, each fins end on the outermost diameter of the disc should be closer to the rear of the car than the begining of that same fin on the inner diameter of the disc. Calipers have arrows on the to distinguish left from right and should also be simply mounted with the bleed screws facing up. Don't forget to bleed both sets of screws on each caliper.
9. Watch out for the tiny metal clips that hold the wear sensor in place on the pad. They are really easy to leave in the old pads or drop and lose.
10. Despite multiple comments on this forum, and after checking both with some BMW parts guys and an experienced ex BMW Tech, NONE of the fasteners in this job are the one time use only type and thus none must be replaced when doing such a brake replacement job. Generally only three types of fasteners are one time use: those with special sealants or thread lockers applied, lobed threads (i.e. for cutting ) and some highly stressed engine fasteners (typically in the engine).
11. Torque values: Although you might get by just fine without torquing these fasteners assuming you have a great feel for torque. Personally, when it comes to wheels and brakes, I simply would not do this job without a torque wrench. You life could depend on it. Really.
    • Rear caliper mounting bolts (OEM BMW): 48 ft lb (65 Nm)
    • Rear caliper to aluminum Brembo adapter bolts (hex drive): 85 ft lb (115 Nm)
    • Front caliper mounting bolts (OEM BMW): 81 ft lb (110 Nm)
    • Front caliper to aluminum Brembo adapter bolts (hex drive): 85 ft lb (115 Nm)
    • Disc to hub hex screws: 12 ft lb (16 Nm) (I just sinched em down tight with a hand held hex key)
    • Wheel lugs: 88 ft lb (120 Nm)
    ALL TORQUE values are for clean and dry ONLY.

I do hope this information is useful for any other potential Bremo DIY-ers. I know these things would have save me quite a bit of time knowing them all in advance.

[swamp2]

OK, finally got her cleaned up enough to get a few pics.

Thanks for the kind words guys.

My wheels are the RAC RG63 in semi-gloss black (from the M3post.com 1st RG63 group buy!).

[JAJ]

Originally Posted by swamp2

(RESERVED)

Great writeup! For anyone doing it, your words of wisdom will be helpful. When I did mine, replacing lines first, then a bbk, I followed someone else's advice and locked the brake pedal in the partially depressed position before I started. All I did was put a stick between the front seat and the pedal (protect the seat with a towel) and run the seat forward far enough to apply the brakes. Then you release the pressure in the calipers by opening and closing the bleed screws (use your catch bottle).

This procedure blocks the duct from the brake fluid reservoir to the master cylinder, so when you disconnect the caliper hoses, they hardly drip at all. So long as the pedal remains depressed, brake fluid can't drain down from the reservoir and make a mess.

Another point about the anti rattle springs on the OEM calipers. They're not particularly stiff and you can just squeeze them with your fingers and they'll disengage and come off. That way they don't go shooting around the place, and you don't risk damaging the caliper paint with a tool.

[aus]

Swamp, post some pics if the car. It'll look sweet with the brembos.

[Rshane]

Great ınfo SWAMP, thanks. I´ve surfed around a great deal on thıs sıte and couldn´t help but notıce, you contrıbute a great deal of good ınfo to thıs forum.

Just saw the pıcs....sweet. Yellow calıpers really complıment the wheel and car color combo. I have been thınkıng of eıther sılver or possıbly gold calıpers for my Lemans Blue. I wıll have to do some photoshoppıng to get an ıdea of how ıt wıll look.

[MNm3]

Pics please. I am looking at this system for my car. What wheels are you running? I've got the stock 19"s but have an 18" track setup.

[swamp2]

for new pics.

[Checkcaptain]

Excuse me, but I guess you mixed up left and right callipers...

[JAJ]

Originally Posted by Checkcaptain

Excuse me, but I guess you mixed up left and right callipers...

Checkcaptain - where have you been? Brembo always puts the bleed screws at the bottom of the caliper.

[swamp2]

Ugh, what a royal FU... I was so careful to get the rotors on the correct side but I botched the front calipers. The calipers not only have the bleed screws up but they have some arrows which indicate rotation direction. Luckily the only significant difference is the sizes of the pistons on the leading vs. trailing edges and that insures proper pad pressure and wear. There are no structural nor safety issues. Car stops fine. I certainly did a bit of testing before cruising around... I'm planning a track day soon so I'm glad someone caught this... Thanks guys. Another reason I enjoy this forum.

[BMRLVR]

Well Swamp, you are very knowledgeable in your posts but this mistake is a little disturbing. Bleed screws are always at the highest point no matter what since air will always be trapped at the highest point in the caliper. Please address this ASAP since you still have air in your brake system....... there is no possible way to bleed the system unless the bleed screws are at the top of the caliper....... I wouldn't want you or anyone else to get hurt from a brake failure. There would be big consequences in the event of an accident especially if they found out you did the work yourself.

I am sure you will never make this mistake again.

By the way, the Brakes/RG63's look awesome on your car!!!

[swamp2]

Yes, big mistake but not as tragic as you make it sound... No one is perfect...

1. Brakes are fully bled. There is no air in the system. The pedal is hard as a rock. That simply does not happen with air in the system. There are still relative high spots in the brake lines and the rest of the system even when bleed screws are oriented properly. As long as you get the fluid flowing during the bleed you can remove all air.
2. There are no structural problems. Everything fits great and everything is torqued. Thus there is NO possibility here of a catastrophic failure.
3. Car was tested lightly and moderately before heading on to the street and only lightly driven after that point.
4. Brakes will be swapped to correct sides before any more driving (obviously to insure proper pad pressure distribution and wear).

[BMRLVR]

It was an honest mistake, I am glad someone noticed it though!

[swamp2]

Thanks again Checkcaptain and BMRLVR!

Got everything sorted out this evening. I also used JAJs tip and added that to the original post along with tips on orientation. Will get some updated/replacement pics up soon too, mostly to save further embarrassment

[JAJ]

Originally Posted by swamp2

Thanks again Checkcaptain and BMRLVR!

Got everything sorted out this evening. I also used JAJs tip and added that to the original post along with tips on orientation. Will get some updated/replacement pics up soon too, mostly to save further embarrassment

By the way, I trimmed my post - I'll replace it completely when you replace the pix.

You might make the point in your initial post that a common error with the rear brakes is to try to take the rotor off with the hand brake applied. It won't move, of course.

[swamp2]

Originally Posted by JAJ

By the way, I trimmed my post - I'll replace it completely when you replace the pix.

You might make the point in your initial post that a common error with the rear brakes is to try to take the rotor off with the hand brake applied. It won't move, of course.

No worries, it is a bit embarrassing but no need to erase "history". No one is perfect. Cheers.

[biglare]

Nice write up regardless. Color combination also looks great!

Looking forward to seeing your car very soon!

[adc]

I used a different method to unstick the seized rotors - clamped them against the caliper brackets with a C clamp, then tightened just about 2mm, to break the corrosion film. Once the rotor has moved a little bit, remove the clamp and it's done.

Can anybody think of a reason this can cause a problem?

[swamp2]

^ Sounds like an OK method. I wouldn't recommend it in general though.

The caliper brackets are really designed to be the stiffest and strongest in the direction parallel to the discs travel direction through the pads. In other words the force you applied is more or less perpendicular to that direction. Almost for sure that is a weaker load direction. That being said these brackets are very strong/"beefy" so I'm sure it did not get anywhere close to a yield/damage point for the load you put into them.

[disapr]

I’d like to add that step 2 ‘Reduce the mess’ is a brilliant solution! I locked my brake pedal about half way down with a section of jack handle and a t-shirt, bled off the initial pressure from each caliper and I didn’t have a single drip when I disconnected the lines! – Thanks swamp2, JAJ!

Also - my front rotors came off with no issue but both of my rears were pretty frozen on. I tapped the bottom of the rotor gently with a dead blow to slightly pivot it on the hub and then squirted some WD40 into the disk-to-hub bolt holes so that it could gravity penetrate down between the disk and the hub. After about 15 minutes they both popped off with an easy tap from the dead blow.

[spdy330]

First off great write up. I am going to bring this back from the dead.

I wanted to thank you for providing the torque settings for this kit. I just readjusted all the bolts to your specs this evening.