Front bakes grabbing, grinding, and chirping after suspension refresh

[rwmorrisonjr]

Just did the full front suspension refresh on my 2012 and had it aligned, so all is good there. However, when I hit the brakes lightly, I'm hearing a faint chirping sound that I hadn't heard before. When I hit the brakes hard, I hear some grinding, suspension groaning, and the truck wants to dive to the right a bit. I've checked all the front bolts and re-torqued them just to be sure, and I've checked both brake calipers and everything is in place properly and torqued to specs. Front wheels also seem to be dragging when I spin them which isn't normal. I did compress the calipers prior to removing them and pumped the pedal before road testing. Should I give it a few days of regular driving and let is all settle in before trying to chase this down? Other than the noises, the truck drives, rides, and brakes normally.

Pads and rotors are only one month old, all Ford parts.

 

[2020FordRaptor]

Just did the full front suspension refresh on my 2012 and had it aligned, so all is good there. However, when I hit the brakes lightly, I'm hearing a faint chirping sound that I hadn't heard before. When I hit the brakes hard, I hear some grinding, suspension groaning, and the truck wants to dive to the right a bit. I've checked all the front bolts and re-torqued them just to be sure, and I've checked both brake calipers and everything is in place properly and torqued to specs. Front wheels also seem to be dragging when I spin them which isn't normal. I did compress the calipers prior to removing them and pumped the pedal before road testing. Should I give it a few days of regular driving and let is all settle in before trying to chase this down? Other than the noises, the truck drives, rides, and brakes normally.

Pads and rotors are only one month old, all Ford parts.

I'd take it back where you had them aligned. Maybe they'll find what's wrong FOR FREE.

 

[rwmorrisonjr]

Duplicate post

 

[rwmorrisonjr]

UPDATE: Truck is still pulling to the right under hard braking and both front wheels are running very hot to the touch. Did a very low speed brake test in my driveway and when I hit the brakes, the steering wheel pulls to the left, then straightens out when I release the brakes; this happens going both forward and in reverse.

Fluid reservoir is full above the full line to the bottom of the filler neck and the pedal isn't as firm as it was before I did the work. Not sure what changed since I didn't do anything to the brakes other than remove & reinstall them. Thinking either calipers are seized after compressing them (OEM, 168k. miles) or flex lines (OEM) might be collapsed, but don't look damaged.

Any thoughts or suggestions?

 

[David Schaefer]

Did you try bleeding the brake lines already? one side braking stronger than the other sounds like how a skid steer works. Also, if you hear grinding when you use the brakes, it doesn't take long to show the scars somewhere (on the rotors, on the pads, etc) You might have to disassemble all of it and take a very close look.

 

[rwmorrisonjr]

Did you try bleeding the brake lines already? one side braking stronger than the other sounds like how a skid steer works. Also, if you hear grinding when you use the brakes, it doesn't take long to show the scars somewhere (on the rotors, on the pads, etc) You might have to disassemble all of it and take a very close look.

Not yet, but that's on the list. No grinding, just some pulling to the right and grabbiness when hard barking. The reservoir is overfilled so I'm going to remove some fluid to see if that helps before going further with bleeding and replacing parts.

 

[David Schaefer]

Not yet, but that's on the list. No grinding, just some pulling to the right and grabbiness when hard barking. The reservoir is overfilled so I'm going to remove some fluid to see if that helps before going further with bleeding and replacing parts.

Your OP mentioned grinding, did that go away?
I used a turkey baster to remove excess fluid. My wife got mad so Ihad to go buy another one as I now had a "garage only" turkey baster! LOL

 

[rwmorrisonjr]

Your OP mentioned grinding, did that go away?
I used a turkey baster to remove excess fluid. My wife got mad so Ihad to go buy another one as I now had a "garage only" turkey baster! LOL

Yes, it went away once things settled in a bit. Just used my bleeder kit to remove the extra fluid, will road test it in a bit to see if that helps.

 

[David Schaefer]

Yes, it went away once things settled in a bit. Just used my bleeder kit to remove the extra fluid, will road test it in a bit to see if that helps.

Did you bleed the lines too, down by the brake caliper to make sure no air was in the line and that the fluid looked good?

 

[rwmorrisonjr]

Did you bleed the lines too, down by the brake caliper to make sure no air was in the line and that the fluid looked good?

Not yet since I didn’t crack the system when I did the other front end work. Will do that next if the road test sucks. Fluid is about two years old and still looks good.

 

[David Schaefer]

Not yet since I didn’t crack the system when I did the other front end work. Will do that next if the road test sucks. Fluid is about two years old and still looks good.

I agree, it's a long shot that you actually need a bleed. It's just one of the things I thought to try, especially since you had extra fluid in the reservoir. IMO, removing the extra fluid from the top should have zero impact on the skid steer affect. Please let me know if I'm wrong about that.

 

[purevw]

My concern would be the calipers. I always rebuild or replace them any time I do a brake job, as they often partially seize after the piston position is changed due to new pads. When I worked as an NIASE mechanic, it was considered standard procedure. The brakes may work, but the pads do not fully release the rotor, causing extreme wear and heat.

 

[David Schaefer]

OP: How many miles on your Expy?

purevw (NIASE mechanic) - that seems overly cautious and would add a lot more expense & work to a brake job. I can't argue new parts wouldn't be better in every case, but IMO, it isn't always necessary to replace the calipers. In fact, I never have and although I've probably only done less then 20 DIY brake jobs, I've never had an issue with a caliper/piston seize.

 

[rwmorrisonjr]

My concern would be the calipers. I always rebuild or replace them any time I do a brake job, as they often partially seize after the piston position is changed due to new pads. When I worked as an NIASE mechanic, it was considered standard procedure. The brakes may work, but the pads do not fully release the rotor, causing extreme wear and heat.

OP: How many miles on your Expy?

purevw (NIASE mechanic) - that seems overly cautious and would add a lot more expense & work to a brake job. I can't argue new parts wouldn't be better in every case, but IMO, it isn't always necessary to replace the calipers. In fact, I never have and although I've probably only done less then 20 DIY brake jobs, I've never had an issue with a caliper/piston seize.

Purevw: that's my plan. If the fluid removal doesn't help, I'll go the new flex lines and calipers route along with a fluid swap to be safe.

David: 168k miles

 

[purevw]

Purevw: that's my plan. If the fluid removal doesn't help, I'll go the new flex lines and calipers route along with a fluid swap to be safe.

David: 168k miles

Yes, I forgot the lines. I had that problem with my '94 Ranger. For whatever reason, the line was not allowing fluid to return. Perhaps there was also a delay in actuation, but I didn't sense any. But it did absolutely cause brake drag.

 

[David Schaefer]

Giving thought to purevw's response about a piston seizing in a brake caliper. 168K miles is quite a few. If it were mine, I'd remove the caliper and note where the piston was. I'd probably mark it with a sharpie. Then I'd carefully compress the piston like I would for new pads. Yours might not go in much. Next, I'd have my wife slowly press the brake pedal, to see if the piston moves up to the line I marked. "hint, very slowly" I would not want the piston to come out and make a fluid mess on the floor!. I would compress it again and repeat, making sure each way is smooth and like normal. After a few cycles, reassemble and go for a test drive. If it still acted like a skid steer, I'd replace the caliper(s), bleed the lines and hope you got it fixed.

 

[rwmorrisonjr]

Ok, here we go. Just pulled both front brakes off and they're both dragging the rotors. When I compress the pistons, they both work properly and come out evenly when I apply pressure, but don't retract when I let off the pedal. I don't see how both calipers can go bad at the same time, but I could see the lines going since they're OEM. Going to try the lines first then the calipers.

I also found my clunking noise. The MF's at Firestone where I had the alignment checked didn't tighten the right LCA when they had it on the rack, so that's also contributing to the problems! I'll need to find a real alignment shop when this is all done!

 

[Trainmaster]

The calipers don't retract. The pressure is simply relieved from them and they are free to release as the rotor turns. Some drag is normal. There should be no reason to change them if they freely are pressed back in when replacing the pads and they don't leak.

Some hoses can be problematic. But those too are fine if the calipers release their grip on the rotors.

 

[rwmorrisonjr]

The calipers don't retract. The pressure is simply relieved from them and they are free to release as the rotor turns. Some drag is normal. There should be no reason to change them if they freely are pressed back in when replacing the pads and they don't leak.

Some hoses can be problematic. But those too are fine if the calipers release their grip on the rotors.

Thanks for the info. The calipers aren’t leaking and retract smoothly when I compress them. However, they aren’t releasing to allow the rotors to spin freely without a lot of drag. That’s why I’m focusing on the hoses since I moved them around a lot when I did the other front end work.

 

[rwmorrisonjr]

UPDATE: I tightened up the LCA mount bolts to torque and the nose diving and grabbing has stopped! I also reinspected the calipers and shoes, replaced the slide pin dust boots, verified the calipers are sliding, and bled a bit more fluid out directly from the bleed screw. I did a short road test around the neighborhood and to get my daughter at school and things seem to be working better.

I called Firestone and told them what I found, and they want me to bring it back tomorrow to have them realign it. That’ll be a better road test for the brakes too. Fingers crossed this will be the beginning of the end of this adventure!