2001 Dodge Ram 1500 with 158,000 miles, the front left brake has been overheating. I have replaced the pads ,rotor, caliper and brake hose. Im still having problems especially during stop and go driving. When they get hot they start slipping. someone told me maybe the proportioning valve is bad. I would like to know if it could be anything else before I replace it.

Did you replace all those parts on BOTH sides of the truck?

Are you getting any pulling either on or off the brakes?

Are the slide pins moving freely?




78 Corvette Pace Car For Sale-18k mi orig-Florida

I only replaced those parts on the drivers side, it was pulling to the right before i replaced the caliper. now it is just overheating just on the drivers side, almost to the point of brake failure. I need some help on this one. I use this truck for work and family. I also live and work in the city so it is crucial that I get this fixed as soon as possible. If anyone has any idea of what could be wrong I would like to hear your feedback.


thank you

You can't expect equal braking when only changing parts on one side of the truck. I'm not saying that's your problem but it definitely wasn't repaired correctly.




78 Corvette Pace Car For Sale-18k mi orig-Florida

why was it overhetin before I replaced everything

I wouldn't even begin to guess knowing the brakes were only done on one side of the truck. The timing alone points to an installation error but the problem could have been misdiagnosed from the beginning.




78 Corvette Pace Car For Sale-18k mi orig-Florida

On that system I would probably be looking for signs of contamination (swollen or disformed rubber gasket on the master cap, brk fluid that looked thick or just not right) if any type of petroleum product got in there, that wouldn't be good.

If that checked out I would bleed the whole system, make sure you are getting fluid to the rears. The frts do the highest percentage of the brking but if the rears stop that would definately start overheating the frts............

I replaced the master cylinder and did a full flush, now both fronts
are getting very hot. maybe proporting valve could be tripped? how do
I fix? is that the problem

It sounds like you may have had a contamination problem. Merely flushing won't resolve that. Every piece of rubber will swell and have to be replaced.




78 Corvette Pace Car For Sale-18k mi orig-Florida

To add: Sometimes brake will pull to better side after one gets hot/too hot called brake fade. As Hammer said it wasn't done right and if both weren't done or non brake fluid ever used it would cause problems especially after bleeding if only bleeding one side if that's what happened.

When someone mistakes an oil to top off master cylinder's reservoir the oil should stay on top. If there was any question you quickly remove all fluid from reservoir.

Now that both are hot is suggests to me the master cylinder has an issue or allowing fluid return OR once I installed a new master that was defective at returning fluid - fine cool and at 6-8 miles brakes applied themselves from expansion of fluid from using brakes or even engine heat near lines. Drove the car myself using parking brake and it did it to me without touching regular brakes.

Rubber will not tolerate oils in a brake systems ever TMK,

T
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Tom Greenleaf - MetroWest, Boston
http://acsource.net/acforum/index.php