What have you done to your mustang today?

StockishS197

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Replaced my brakes, took it out to bed them in following the directions in the box.. front pads were smoking when I pulled up, car has almost no stopping power now. Literally NEVER had a brake bed, on any vehicle, go wrong until this one.. need to make sure I'm not losing fluid somewhere (pedal doesn't hit the floor so I don't think so).. maybe the pads glazed over, the instructions in the box were, um, aggressive for how to bed them.
Some smoking is normal for bedding in, but shouldn’t have any issues stopping.

If it’s excessive, I would check the caliper slide pins and pistons to see if they are seized/not retracting.

If it was a fluid issue, you would have a spongy pedal. Did you also bleed out fluid after the pad swap or just compress the piston and keep the same fluid?
 

Forty61

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Some smoking is normal for bedding in, but shouldn’t have any issues stopping.

If it’s excessive, I would check the caliper slide pins and pistons to see if they are seized/not retracting.

If it was a fluid issue, you would have a spongy pedal. Did you also bleed out fluid after the pad swap or just compress the piston and keep the same fluid?

It seemed a little excessive but the instructions for bedding were a little more aggressive than I would normally do.

I lubed everything when it went back together, everything was dry and covered with brake dust but now it all clean and shiny with fresh grease.

Pedal feels firm in the driveway but step hard on the brakes and it's a little spongy. Never hits the floor but it's not confidence inspiring either. Did not bleed the system, just compressed the pistons using the compression tool like last time I did them.
 

JC SSP

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Very interesting. Did you pump the brakes before leaving for the bedding procedure? Did you crack any of the bleeder screws?

If you glazed them… try using emery cloth on the pads and rotors & try the process again.
 
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StockishS197

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It seemed a little excessive but the instructions for bedding were a little more aggressive than I would normally do.

I lubed everything when it went back together, everything was dry and covered with brake dust but now it all clean and shiny with fresh grease.

Pedal feels firm in the driveway but step hard on the brakes and it's a little spongy. Never hits the floor but it's not confidence inspiring either. Did not bleed the system, just compressed the pistons using the compression tool like last time I did them.
I would bleed through the calipers and see if it improves. Compressing the calipers pushes the old fluid back into the lines and could cause a spongy pedal. If the fluid is original, might be worth just vacuum bleeding everything with fresh fluid.
 

Forty61

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Very interesting. Did you pump the brakes before leaving for the bedding procedure? Did you crack any of the bleeder screws?

If you glazed them… try using emery cloth on the pads and rotors & try the process again.
I pumped them and they felt decent, didn't touch any of the bleeders. Emery cloth is a good idea, I do have a spare set of pads somewhere too.

I would bleed through the calipers and see if it improves. Compressing the calipers pushes the old fluid back into the lines and could cause a spongy pedal. If the fluid is original, might be worth just vacuum bleeding everything with fresh fluid.
Fluid isn't new but it's not original either, we bled them at the last replacement which was a decent time but not many miles ago.

I will try find the time and daylight to dick around with it.. kind of annoying to go in on brakes that work to fix a small squeak, which I never found the cause of, and come out with brakes that are now quiet but don't work well enough to drive with.
 

JC SSP

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Jake up the car and spin the tire to see if a caliper is binding. I am wondering if you have a caliper piston stuck or brake hose collapsing?

I personally would do a full brake bleed and flush. Start RR, LR and then RF & LF.
 

GriffX

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Compressing the calipers pushes the old fluid back into the lines and could cause a spongy pedal.
Why? It is a closed system and fluid cannot be compressed regardless of age.

Never did a brake in procedure - I don't have the empty road for this, 100 miles careful driving was enough.
What pads did you install?
 

graybeard

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Bought new 18" wheels and tires today for the 2005 GT to replace the 20" that were on the car when purchased.

The new wheels are 18" x 8.5" with a 30 mm off-set. New chrome lug nuts came with the wheels.

Tires are 235/45/R18 front and back. I'll post a photo or two of the new wheels and tires on the car tomorrow.

20260224_Downsized.jpg
 

Gabe

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Bought new 18" wheels and tires today for the 2005 GT to replace the 20" that were on the car when purchased.

The new wheels are 18" x 8.5" with a 30 mm off-set. New chrome lug nuts came with the wheels.

Tires are 235/45/R18 front and back. I'll post a photo or two of the new wheels and tires on the car tomorrow.

View attachment 114152

That size tire is pretty short at 26.3" .... S197 fitment is usually around 27-27.5" tall
 

graybeard

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L
Bought new 18" wheels and tires today for the 2005 GT to replace the 20" that were on the car when purchased.

The new wheels are 18" x 8.5" with a 30 mm off-set. New chrome lug nuts came with the wheels.

Tires are 235/45/R18 front and back. I'll post a photo or two of the new wheels and tires on the car tomorrow.

View attachment 114152
Cool wheels. Did you get hub-centric rings too?
I'm not sure what hub centric rings are, but they did come with caps that snap into the hub bore.
 

StockishS197

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I'm not sure what hub centric rings are, but they did come with caps that snap into the hub bore.
Most aftermarket wheels, especially wheels that are not specific to mustangs, are lug centric vs hub centric like OEM wheels.

Hub centric simply means the hub face fits inside the center bore of the wheel. Hub centric rings ensure the bore of the wheel is centered on the hub.

Most aftermarket wheels are lug centric which is usually less strong to lateral forces since you are using only the lugs, and can also lead to vibrations.
 

JC SSP

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Most aftermarket rims are lug-centric meaning they align via the lugs. OEM and quality aftermarket rims which usually are vehicle specific are hub-centric, where the rims fit snuggly over the hub.

Hub centric rings (aka spacer) take up the slack between the rim and hub, providing a tight fit which trans lates to no vibration or wobble.

You can still get a great ride with lug-centric, but these rings make easier.

1772028396535.png
 

graybeard

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That size tire is pretty short at 26.3" .... S197 fitment is usually around 27-27.5" tall
The spec I found for OEM tires (235/55/R17) is 26.77"
Yes, the new tires are a bit shorter.

The 285/35/ZR20 Nittos that came with the car, are suppose to have a 27.87" OD.
Too tall.
 

graybeard

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JC SSP,
The 2005 Mustang wheel hub diameter is reported to be 70.5 mm.

The hub bore in these new wheels is 73.1 mm.

The hub ring would be approximately .06" thick.
Are there hub rings made that thin?

(There is more to specifying a wheel than I lead myself to believe)
 

JC SSP

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The hub-centric rings come in many different sizes. Usually, the manufacture of the rims or whoever sold you the wheels has a chart/list with the specs and options (plastic, aluminum, nylon, etc.)

Please double check the size... Also, I am not affiliated with this company, just a quick Google search, there are many vendors out there.

 

graybeard

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JC SSP,
Thank you for the info. Bookmarked.

The dealer I bought from contacted Ace Wheels this morning. They told him hub rings were not necessary, just use the lug nuts provided.
I may not be seeing some feature on this wheel or the lug nuts.
 

Gabe

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The spec I found for OEM tires (235/55/R17) is 26.77"
Yes, the new tires are a bit shorter.

The 285/35/ZR20 Nittos that came with the car, are suppose to have a 27.87" OD.
Too tall.

285/35/20 is actually a great size for the back of an S197 Mustang.
Hell, I'm running 275/35/20 on my wife's '08 GT500. That tire is about 27.5" tall and looks great on there.
I've run 305/35/20 rears on my '13, that size is 28.4" tall and it was fine. No rubbing, no issues.

On OEM 18's the car comes with 235/50/18 which is about 27.25" tall.

2007-2009 GT500 came from the factory with 255/45/18 fronts and 285/40/18 rears both 27" tall.

Yes, I'm going on and on. I guess I just really don't care for short/thin tires.

But sometimes it takes having the first-hand experience to believe it.
 
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