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brent 02-21-2010 10:02 AM

Front brake job questions.
I'm going to be replacing my front disc brakes/rotors today. They're warped and rather than resurfacing the rotors, I'm just going to replace them. I picked up the OEM Mopar "make it new" brake kit (PN VWKXK868AA)

So I got some packets of Permatex ultra disc brake caliper lube, antiseize, and some disc brake quiet for the job. I feel like I've done my homework and am ready to go.

My questions are:

1. Is it necessary to bleed the brake lines for the procedure? I noticed the other forumites haven't and the service manual doesn't call for it. However, generic instructions on the internets typically recommend bleeding and topping off the master cylinder.

2. I think I got the inboard and outboard pads figured out but I wanted to ask. On the mopar set, there are no indicators other than red and yellow paint and an extra set of pins on the outside.

Top outboard (red paint, 4 pins pins)
Bottom inboard (yellow paint, 2 pins)

Can someone verify my thinking here?


mon_21 02-21-2010 10:27 AM

Re: Front brake job questions.
I replaced all four brakes and all four rotors on my jeep without bleeding it. Topping off the master cyclinder prevents air from going inside the line while in the process of bleeding it.

Its not really necessary but it wont hurt you either if you do. As to your brake pads, I have a WJ so I couldnt really comment on it.

06HemiLtd 02-21-2010 10:52 AM

Re: Front brake job questions.
you don't need to bleed the brakes unless you're disconnecting the brake lines or changing calipers. you should still siphon a small amount of brake fluid out of the master cylinder and leave the cap off the reservoir. you'll have to push the pistons back into the caliper which forces the fluid back into the master cylinder.

robpp 02-21-2010 10:58 AM

Re: Front brake job questions.
and dont sweat the inner outer stuff, you can figure it out when you take out the old pads by comparing........

and for the master, as stated above, NO Bleeding, but you will push fluid up to the master when you squeeze the pistons so what I do is open the master, and put a substantial rag under it so if it does overfill, it goes on the rag.

brent 02-21-2010 08:26 PM

Re: Front brake job questions.
Thanks! Got the fronts and the rears done today! Nice!

Scottina06 02-21-2010 09:44 PM

Re: Front brake job questions.

brent 02-22-2010 09:59 AM

Re: Front brake job questions.
ya, threw some wagner thermoquiets on the back but didn't replace the back rotors. Used some brake clean and a scrubber to (hopefully) remove the existing glaze.

So far, I've been happy with my work. Need to put some miles on them to get them fully broken in but I did go through the bedding procedure possibly erroring on the side of caution.

Rich 02-22-2010 11:37 AM

Re: Front brake job questions.
I know your done now, nice!
I had similar questions prior to doing my front & rears. I though it was a standard rule of thumb to never push brake fluid back through an abs system? So the advised method would be to crack the bleeder when pushing the pistons back. I did not do this for ease of the job, but is this really not necessary with our setups?

robpp 02-22-2010 11:45 AM

Re: Front brake job questions.
never heard of that, but i am old school. have done dozens of brakes on abs systems. i always just open the master and put a rag under it if it overflows......use a c clamp to compress the pads against the pistons.

Rich 02-22-2010 01:11 PM

Re: Front brake job questions.

Originally Posted by robpp (Post 155916)
never heard of that, but i am old school. have done dozens of brakes on abs systems. i always just open the master and put a rag under it if it overflows......use a c clamp to compress the pads against the pistons.

Same here, except I "try" to remove excess before it overflows. But just a quick search turns up stuff like this:

scottydog 02-22-2010 02:30 PM

Re: Front brake job questions.
I bleed the brakes when I do the pads/rotors. The old fluid collects water and starts looking pretty grim. It's an easy thing to do while the wheel is off. Be sure and use a turkey baster to take out the old fluid from the BMC, then fill with new. You can use a bleeder, or just open the valve and take a break while it gravity drains.

If you squeeze the caliper piston too much the excess pressure can break the ABS. Just do it slowly, or you can open the valve.

Make sure you torque the caliper bolts to 125 ft-lb, slide pins 18.

brent 02-22-2010 11:13 PM

Re: Front brake job questions.
Ya, torqued the caliper bolts to 125 and slide pins to 18.

I may bleed my brake lines this weekend. Sounds like fluid vapor (water) can build up in there and bleeding them should be done when replacing pads. Good article.

I'll follow this recommendation instead of compressing the calipers since the pads have already been replaced.

Use Mopar brake fluid, or an equivalent quality fluid meeting SAE J1703-F and DOT 3 standards only. Use fresh, clean fluid from a sealed container at all times.

Do not pump the brake pedal at any time while bleeding. Air in the system will be compressed into small bubbles that are distributed throughout the hydraulic system. This will make additional bleeding operations necessary.

Do not allow the master cylinder to run out of fluid during bleed operations. An empty cylinder will allow additional air to be drawn into the system. Check the cylinder fluid level frequently and add fluid as needed.

Bleed only one brake component at a time in the following sequence:

1. Fill the master cylinder reservoir with brake fluid.
2. If calipers are overhauled, open all caliper bleed screws. Then close each bleed screw as fluid starts to drip from it. Top off master cylinder reservoir once more before proceeding.
3. Attach one end of bleed hose to bleed screw and insert opposite end in glass container partially filled with brake fluid . Be sure end of bleed hose is immersed in fluid.

4. Open up bleeder, then have a helper press down the brake pedal. Once the pedal is down close the bleeder. Repeat bleeding until fluid stream is clear and free of bubbles. Then move to the next wheel.

More fun! At least it looks doable without having to jack up the vehicle. Just need a good helper monkey.

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