Servicing Front Brakes

[quick2tr]

12000 miles and 5 Track days so far and my front pads look shot. Leading edge on all 4 front pads have worn 3-4 times faster than trailing edge. This might also explain why I have felt a slightly rougher (mild grind, but nice bite!) braking after a few hot laps. Im assuming since the rears are not the same, this is strictly a result of the tracking and that these stock street pads are abrading away as expected.

As much as I hate wrenchin now, I might as well get used to doing this part myself. Does anyone know the answers to the following questions :

Proper torque for the 10mm headed caliper retaining bolts? Anti-seize or locktite?

Without removing the caliper first, its hard for me to see what tool (if any) I will need for removing the retaining pins. Are these held in by the caliper bolts? If they are threaded, what is the tool and torque?

Should I drop a set of CCoupe front pads in for both track/street use? Or is using the CCoupe pads on the street a dangerous no-no? Do the pads go in dry?

Proper torque for the bleeder valves? I had these set to 12lbs and the front calipers bleeders were weeping out a bit of my SRF after a few hot sessions.

Thanks.

 

[GR8_ASP]

Why are you removing the calipers?

To install new pads all you do is remove the two pins and clip, retract the pistons by squeezing the pad toward the caliper and inserting the replacement.

Real easy and a 2 minute job + wheel removal.

I use brakeman 3 pads for the track. I found the stock pads not capable of higher brake temps on the track. The rear pads wear at less than 1/2 the rate of the front.

 

[Vipera Russelli]

I don’t understand why your pads would be wearing 3 to 4 times faster on the trailing edge. In my experience I’ve noticed that the pads do not wear completely evenly from the leading edge to the trailing edge of the pad, but the difference is pretty minor (less than a millimeter in all cases--I've used a micrometer to measure at different stages of wear). Given that your pads are over a centimeter thick when new (not counting the plate), 3 to 4 times wear sounds like several millimeters of difference across the pad surface. Maybe some of your caliber pistons are sticking, I don’t know, but that doesn’t sound right to me. And although I used Brakeman 3s for the track, I did wear out my one and only set of OEM pads at the track and they wore petty evenly as well.

As GR8 ASP points out, the front pads wear more quickly than the pads on the rear. Most of the stopping force occurs at the front. Additionally, my front-driver-side pads wear more quickly than my front-passenger-side pads. I attribute this difference to the fact that I drive mostly right-hand-turn tracks and the front-passenger wheel doesn’t do as much stopping since it spends more time with less weight on it, and sometimes halfway off the ground. My rear pads wear at about half the pace of my front-driver pads.

Changing pads is really easy and does not require that you remove the calipers (which is pretty easy too, and something you’ll do when you replace your rotors, which is also easy). To change the pads, remove the wheel, and then simply tap the caliper pins out with a light hammer and nail (they are not threaded), removing the anti-rattle spring between pins, and then use a C-clamp on the caliper outside and on the lip of the pad’s backing plate to squeeze the pad away from the rotor and in so doing force the pistons back into their sleeves. Pull the now loose pad out by hand and replace it with a new pad before using the C-clamp on the other pad. Once two new pads are positioned, tap the pins back in, replacing the anti-rattle spring between pins. The whole process takes about three to five minutes per wheel and no more.

I use Brakeman 3s all the way around without any issues. Others have used stock pads in the rear and CC pads in the front. And Brakeman now has a Brakeman 4, although I haven’t tried it.

I’m not sure of the torque specs for the calipers screws or bleeding screws. I just torque them to what feels right to me, which is pretty tight. I have a manual and could look it up, I suppose.

I hope at least some of this helps.

 

[Steve-Indy]

From the 2004 Viper Service Manual...torque for bleeder screw is 10 N-M...or 88 in-lbs.

Would suggest finding a 2004 Service Manual. ..sources include buying from Woodhouse, Tator, or PartsRack...or, ordering same from D-C via:
https://techauthority.gltghosting.com/webapp/wcs/stores/servlet/CustomerHome?storeId=10051&langId=-1&catalogId=10051

 

[quick2tr]

Thanks for the info, exactly what I needed.

 

[Vipera Russelli]

From the 2004 Viper Service Manual...torque for bleeder screw is 10 N-M...or 88 in-lbs.

Would suggest finding a 2004 Service Manual. ..sources include buying from Woodhouse, Tator, or PartsRack...or, ordering same from D-C via:
https://techauthority.gltghosting.com/webapp/wcs/stores/servlet/CustomerHome?storeId=10051&langId=-1&catalogId=10051

Don't forget to tell DC that you're a VCA member. It makes a significant difference in price.

 

[quick2tr]

Pistons moved freely enough that I could push them in with my fingers. Ok, maybe not worn 3-4 times faster on the leading edge . . . But it is noticeable. To be fair, I did track the car 3 times last year without bleeding or changing the fluid. Possibly air in the caliper could explain uneven wear.

The Brakemans seem to be popular with you trackrats, so I will try them on just the fronts as GR8_ASP suggested in the ABS thread.

Thanks again for all your help!

 

[Racer Robbie]

You really have me on this one. I would check to make sure all the pistons move freely out without hanging up. Also I would bleed the whole system just in case there is a little air pocket trapped in the top of the caliper which is keeping the top pistons from moving out at the same rate as the bottom pistons. This was always a common problem on Jeet CJ front calipers. If you bleed them with the caliper in place you would trap air inside of them as the bleeder screw did not face straight up at 12:00. We would remove the caliper, turn it towards 12:00, and then bleed it. Hope this helps.

 

[Steve-Indy]

...and, to "bleed the whole system" on your Viper (and any other ABS Viper) you will need a DRB III.

 

[GR8_ASP]

...and, to "bleed the whole system" on your Viper (and any other ABS Viper) you will need a DRB III.

Yes, to open the valves.

 

[Racer Robbie]

You are quite correct. Above in my post was my findings on an old jeep which drove us crazy with no brake pedal until we realized that the bleeder had to be upright to remove all the air. You could not do it with the caliber attached to the jeep.

 

[BigSaleen]

Thanks for the post. I tried to replace my "squeal at mid pressure" EBC greens myself but couldn't break the calipers apart. Good to know that you don't even have to do this to change the pads. Will give it another try this weekend and post if I have any problems.