06 Saturn Vue, front brakes drag.
 

2006 Saturn Vue Redline, AWD 3.5L V6. Front disc brakes, rear drum brakes.

The front brakes (usually passenger side) drag after about 20 minutes of driving, I have to stop to let them cool down in order to continue. If they're dragging really bad, it'll feel like the whole car is shaking (not Jeep death wobble shaking, like a bumpy road shaking). This started after replacing the front calipers and rear shoes.

Here's a list of everything I've done:
- Replaced both front calipers, all new hardware and greased
- Replaced both front rotors (old ones are on now, same issue)
- Replaced rear shoes, springs, and drums
- Replaced all 4 rubber lines
- Replaced all 4 bearings and wheel speed sensors
- Replaced master cylinder (with new fluid, system has been bled hundreds of times at this point)
- Replaced ABS pump & electronic module
- Replaced brake booster (no fluid in old one or new one)
- Checked pedal switches, they're not interfering
- Adjusted booster push rod (after doing this the pedal only goes down half way and I get half brake pressure, but they still drag)

In it's current state, the brakes still drag after about 20 minutes, but now the pedal only goes down about half the distance it should, and I get about half brake pressure. All 4 wheels get brake pressure, I jacked it up and made sure. I've since adjusted the booster 2 more times, and bled after every adjustment since I had to remove the master, and same thing. I bought a booster measurement tool but it doesn't fir with this style of booster and master, so I'm basically just guessing.

I'm determining the fronts are dragging by measuring them with a heat gun. Highest I've ever seen was 800F on the passenger but that was only once. Usually now they get up to 300F, but yesterday got up to 500F twice. We originally replaced the brakes because the old fluid was black and the bleeder screws were snapped off both front calipers. For a while we had an issue with a soft brake pedal and a clunk when disengaging the parking brake, but that stopped when we replaced the wheel cylinders (this was before we replaced the front brakes, and before the drag started.)

I know I made this really long, but I've been dealing with this since July (it's December as of posting), and I really need some help here. I don't want to get rid of this car, this is a very frustrating issue. We took it to a small town shop once and they said they fixed it, but they made no difference. Any help or ideas are greatly appreciated, thanks.

I by no means am trying to question your ability here since you've gone to this extent.
But just to start with the basics, calipers are on correct side, bleeders up? And no kinks in the rubber hoses?
Is it possible you received a bad soft line for that front passenger side?

Also, do these abs pumps require a scanner to be bled? I can't remember off hand.

If you're in the east Texas area, I wouldn't mind helping out.

No offense taken. The calipers are installed correctly with the bleeders at the top, I bought 4 brand new rubber lines from the local parts store, and I didn't bend or kink them at all during installation. Some people say to use a scan tool to bleed the abs, some say the fluid should go through the abs module during bleeding, and others say to activate the ABS on loose ground a few times before bleeding. I'm taking the car to s shop tomorrow where they have the scan tool, so hopefully that makes a difference.

The fact that the problem persists even with 1/2 pressure (well stopping power so not quite right) let's say reduced power leads me to believe it is related to some obstruction preventing the fluid from being pulled back towards the master.

Remember you're buying parts for an 18 yr old vehicle. Whether aftermarket or oem, if they are application specific for your year Vue, they were likely manufactured over a decade ago. Rubber parts degrade over time, and their physical properties often change as a result.

If they are not application specific for your Vue, that may also be an issue.

Come to think of it, I ran into a similar issue with a 1999 f150 V6 2wd once.
Master was the original cause.
Replaced master, and brakes wouldn't bleed. Super spongy peddle.
Found a small rubber grommet/hose cap/screen looking thing in the master where the line for the rears went into it. Took that out, boom.
That truck does not have abs, though.

Hopefully the shop can get it figured out for you

No solution yet, but here's what happened at the shop:

First we lifted the car off the ground, and after braking a little bit with the car running the wheels locked up. Fronts wouldn't move, rears were stiff but could rotate. Then we tried cracking the bleeder, and fluid actually came out and loosened up the wheels. This is weird because I've loosened the bleeder screw while the brakes were locked up multiple times before and fluid never came out, and it never released them like that.

Their scan tool couldn't connect to the ABS, probably because it's a GM with a Honda engine or something, so I wasn't able to do the ABS bleed. They checked the vacuum line going to the booster and said that was fine, and other than that not much else happened. I tried slamming on the brakes in a gravel parking lot near by (safely of course) and I was actually able to activate the ABS just a tiny bit right at the end of the stop, still not full braking power though. I was along side them with the car to answer any questions and to see what they have to say about it, and in the end the guy's best guess was something electronic isn't communicating properly. He suggested some other places that might have a better scan tool than his, so I might go to one of those places next week.

They didn't end up charging me for anything, so that was nice. I had to make a 3 hour drive right after the shop visit and what's interesting is the brakes didn't drag almost at all on the whole trip. There were a couple times where one rotor was about 50F hotter than the other, but nothing close to what I've been dealing with. Like I said I still have the half pedal weak brakes problem, and I still think that might be something to do with the brake booster rod. I'll try to make a better home-made tool to adjust it closer to perfectly. I'll keep this thread updated as time goes on until the problem is fixed, and keep the suggestions coming.

I would definitely recommend the booster adjustment to obtain proper braking at the earliest.

There seems to be a static pressure building up between the caliper and master / ABS valves that does not reverse when the pedal is lifted. Hence the fluid out the bleeders and the pads are stuck to the rotor.

Based on your almost trouble-free trip afterwards, it sounds as though most of that static pressure was released when you opened the bleeder valve. Consequently, the magnitude of that static pressure was smaller.

Is there a proportioning valve for the brake system?

I'm going to build a tool to get the closest adjustment to perfect as I can, basically because of the shape of my master cylinder I need a pretty large regular shaped brake booster adjustment tool. I can draw a diagram to explain what I'm talking about if that would help.

The regular Vues have a proportioning valve, while the Redline versions (which I have) have the ABS pump that acts as the proportioning valve, at least that's what I've read. This does sound like a proportioning valve issue which is why I was hoping to get the ABS professionally bled at a local mechanic shop, but as you've read that didn't quite work out.

Here's a better explanation for "didn't drag almost at all on the whole trip":

The brakes didn't feel like they were dragging at all for the entire trip, maybe a couple times where the pedal might have felt a small bit stiffer than a few minutes before, but felt good. On one of my stops the passenger rotor rear 10-20F hotter than the driver, and on the very last stop the passenger side was about 40-50F hotter than the driver side, so there was definitely some drag taking place, whether that be on a small lever or just at the end. It was 90% highway driving, but there was lots of stop-and-go traffic in the towns.

I can answer as many questions as you have, it only helps. Thanks

Maybe you should try getting it on a lift again and try bleeding all 4 wheels. You don't say that both front wheel calipers were bled or just one. And you didn't mention bleeding the back ones either. I'd definitely try to get all 4 wheels bled as this sure sounds like a blockage in one of the lines to me. BUT, keep in mind that I'm NOT a mechanic and don't know diddly about the ABS system or how it's supposed to work. It seems kind of odd to me that there's no proportioning valve in the system.