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OK, got the Bendix PBD1351/1352s installed. Need some insights here.

Bedded them in (I think) doing a lot of moderate and heavy braking starting at speeds of 40 - 70 mph. The braking action doesn't feel much different from the factory pads. Certainly not able to activate the anti-lock system easily like Turboner was/is able to. So any suggestions?
 

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Discussion Starter #42
OK, got the Bendix PBD1351/1352s installed. Need some insights here.

Bedded them in (I think) doing a lot of moderate and heavy braking starting at speeds of 40 - 70 mph. The braking action doesn't feel much different from the factory pads. Certainly not able to activate the anti-lock system easily like Turboner was/is able to. So any suggestions?
I did notice a world of difference, but I have no idea what pads were on my car before. (Just bought the car) I still stand by what I said because I can easily lock up my wheels under braking. Possibly they are not fully conformed to the rotor and need for bedding, or factory (and i do mean gm) is close to what the bendix pads are and again, I have no idea what brand pads came with my car when i bought it in march.

To compare I have stock suspension and stock tire sized all season tire. I also had the frond calipers rebuilt after finding some fluid in the boot during first safety inspection
 

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The key thing is you are easily able to lock up your wheels. I cannot.

I am running stock size Michelin Pilot Sport AS/3 all season tires (and PPV dampers). They are the stickier of the all seasons but unless your tires are 'greasy' tires, I doubt that explains the difference.
 

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Discussion Starter #44
I can suggest check piston movement and pin sliders? Also pads aren't jammed in anchors, I had to grind a lot of rust on mine before I had a freely moving pad.

Maybe they just need more bedding? Idono, you should have the ability to lock up wheels, even with an average pad imo.
 

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OK, got the Bendix PBD1351/1352s installed. Need some insights here.

Bedded them in (I think) doing a lot of moderate and heavy braking starting at speeds of 40 - 70 mph. The braking action doesn't feel much different from the factory pads. Certainly not able to activate the anti-lock system easily like Turboner was/is able to. So any suggestions?
Here's where it's important to understand what the details are--specifically, what was done and what was not done in the process--a "pad slap" is what sounds (to me) happened in this case, and the results reported are addressed below.

1. old pads removed, new pads installed - check

2. rotor condition?

3. rotor prep?

4. brake lubricant used?

5. anything else?

Here's the point: unless there are details that have not been divulged, a new set of pads (and especially with different friction material) require that the rotors, at the very least, have the friction surfaces scuffed, to remove the transfer film that has formed from the previous pads.

Bedding the (new) pads is properly done with fresh, clean metal on the rotor cheeks--the old pad film on the rotors actually becomes a contaminant, preventing the new pad from forming it's own transfer film with the rotors.

Options to remove transfer film, in order of preference - least preferable to most preferable--this depends on the rotor meeting all other parameters for continued use--lateral runout, disc thickness variation, friction surface finish:

1. brake lathe to turn rotors, either on-car or off, making lightest cut possible - least preferable because it DOES remove metal

2. scuff rotors using a sanding disc, such as 3M Roloc, or even sandpaper with a block to keep the paper flat on the disc surface

3. scuff rotors using a "flex hone", as offered by Brush Research

Both 2. & 3. are better performed off-car, as reaching inside rotor cheeks is difficult at best on-car. Ideally, a means to spin the rotor is the proper way to do this--in other words, mount the rotor on a brake lathe to do this--with 3. (Flex Hone) the objective is to create a non-directional finish--it has a sort of cross-hatch appearance done properly.

In addition, once rotors are scuffed or cut, they must be thoroughly cleaned to remove all residual metal or potential contaminants. Water and soap is best, then air-drying, but most will likely opt for spray brake cleaner--just be prepared to use lots of it.

4. replace rotors - final/best option to ensure new pads are able to bed and form the transfer film properly

Photo shows a new rotor (custom hat & DBA ring) for an Impala SS -- non-directional surface finish is from flex honing, using a reversible drill motor, with rotor mounted & spinning on a brake lathe. It still required final cleaning to remove any loose metal or other debris/contaminants.
 

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Discussion Starter #46
With new pads being metallic and working with ABRASIVE friction try driving a few days to do the same thing. If you had ceramics before your rotors are coated with a layer of ceramic pad material. Ill post pics later of my rotors with ceramic pads vs to currently after a month with metallic pads

...monday when i get it back from the tint shop.

And maybe bleed your brakes? Air in the system?
 

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I agree with inov8rPPV on the technical prep of old rotors for new pads. But... tried to take the quick and easy way out. If I was going with the expensive Carbothech pads, I would have gotten new rotors. I'll try driving more and see what happens.

WRT other concerns: I check the slide pins on every brake job, these were silky and greasy. The calibers where the pads slot into were clean/rust free, new slide clips were used and a tiny bit of Sil-Glyde put on the pad tabs. The pads slotted into the calibers easily (some brake jobs I had to grind the tabs). I changed and bled the brake fluid a year ago. The pistons are working as the surface rust that forms overnite from rain is cleaned off (I'll check the rear/inside rotor surfaces again). I can lock up the brakes but only with a lot of pedal force and after most of the speed is scrubbed off.


Edit: Just pulled the rear wheels and eyeballed the rotor surfaces. The new pads do need more embedding. The inside rotor surfaces are not quite as shiny as the outsides.
 
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