I have a 95 1500 2wd that has been having a weird moaning sound happen when the brake pedal is pressed. Whenever my wife is in the truck she gets a kick out of mimmicking the sound in an obnoxious fashion and tells me my truck sounds like the lamb toy that she bought for our dog. She nicknamed my truck lammie, so I need to get this fixed before I have to resort to spousal abuse .

It usually only happens at low speeds and happens mostly when pressing the brake pedal. However the sound does happen sometimes at low speeds right before the automatic trans shifts to the next gear, without my foot on the brake pedal. A few months ago the rear brake line sprouted a pinhole and had to be replaced. I bled the brakes starting with the farthest wheel first. A few weeks after that, I started noticing the sound and so I bled the brakes again (using 2 people) and did not see any air bubbles come out, but the sound was still there.

What do you guys think? The rear reservoir did go dry when the pinhole happened, is there a special way to bleed the brakes when this a happens? I remember reading something about holding proportioning valves open but couldn't find any instructions. I was also told that it may be my Power Brake Booster is bad. Any thoughts??

thanks
jasper

 

anyone?

 

You describe a problem/sound that happens with your foot on or off the brake pedal.

As far as as booster problem, you'd have to check that with a gauge.

I also have a 95. And if you live in an area where road salt is used for winters, then it's probably time to replace ALL the brake lines. Where was the hole? How did you bleed the brakes both times? Gravity, pedal, pressure,???????


Try to be a little more specific on the noise. All your belts are good? All the other fluids are at their proper levels?

Let me know.

 

First you don't have to open any valves for a traditional brake bleed (manual); the only time you need to worry about that is if you are using an automatic brake bleeder (like a dealer might). So it sounds like that is not your problem, unless you aren't sure if you got all the air out.

Did any fluid leak into the rear brakes, like on the shoes? If so that can cause some really strange things to happen and might be your problem, it softens the shoes and glazes the drum. If you think this is it you will need to replace the shoes (I am assuming drum brakes) and possibly get the drums machined since they may be glazed due to the fluid and brake heat.

If that isn't it then I would say try to isolate it to the front or rear brakes and determine if you are sure you heard it with your foot off the brake pedal. Plus try to describe it a little better, someone may have had this exact problem before.

Good luck

 

thanks for the responses....

the hole in my brake line happened right around where the gas tank is, about halfway between the cab and the rear tire. Nothing leaked on the rear brakes and the inner tire was dry. The first time I bled the brakes I used one of those one man bleeder kits. I didn't have alot of confidence in it so the second time I my wife help me with the pump and hold method.

The sound is hard to describe. At first I thought it was the abs unit adjusting itself. You know how some cars (or maybe all) will have the abs unit make a noise within the first few minutes of moving, it kinda of sounds like that. The noise is coming from the brake pedal area, either under my dash or right against the firewall. It's not coming from one of the wheels. As ridiculous as this sounds, the noise resembles the sound a goat would make. Its annoying.

It only happens at low speeds, like below 10mph. For example, when I back out of my driveway and hit the brake, it'll make the noise when I press the pedal. As I approach the stop sign at the end of our court, I let off the gas and the sound shows its face. Occasionally when I'm sitting at a traffic light with my foot on the brake, the sound will happen and I can feel something in the pedal like a faint vibration. Also sometimes when I start the truck up, and my foot is on the brake, the sound happens.

hope this helps

thanks again
jasper

 

Wow, that is strange! The only thing I could think of would be the brake booster as you mentioned in the first post. Since it is vacuum operated it would make sense that it would happen while the engine is at a low RPM. A quick check would be to drive and then before stopping put the truck in nuetral and rev the engine to about 2500 RPM. It sounds like the problem happens pretty often, so if you do this a few times and the sound doesn't occur then I would look at the booster or a vacuum leak somewhere. Another way to check for that would be to remove and plug the vacuum line from the booster. Remember you will be driving without power brakes in a very heavy truck so make sure you do it in a remote area and go slow. Even if it goes away it could still be vacuum related instead of being a bad booster.

Please let us know what happens

 

Here is something I just found on the dodgetalk forum
http://www.dodgetalk.com/forums/showthread.php?t=122777
Might be worth looking at.
The forum places * in place of dodgetalk in the link, just replace the * with dodgetalk.

 

thanks for the info...

I'm gonna try the vacuum thing this weekend. If it doesn't point to anything, I'm gonna try bleeding everything again. I'll let you guys know what I find.

 

I can't belive this forum won't let me post a link to another forum or even the name of it. Anyway here is the text from the other forum that I thought you might be intereted in:

There are really several brake problems identified through out the threads. I just completed reading 10 pages back to identify my problem. My problem spongy go to the floor intermittently. Now, I've purge brake lines with help in the past. Years past I didn't have two electronic blocks between the master cylinder and the shoes or rotters(?). Well, by the book: Master cylinder, proportioning valve connections, ABS block connections, right rear, left rear, right front then left front. Amazing, I have brakes. I'll wake up in the morning and give her another try. But no fade to the floor. Folks, I've been to a friends shop, A Brake (un-named) Shop and neither knew about the sequence I picked up here. Hope this helps someone, I've lost a day and a half of work trying to figure it out. Chris in Memphis.

Remember, I didn't post this and I wanted to link to it, but was unable to.

 

yeah I figured that was a moderator edit or something. When I attempted to reply to your post, the quoted text in my reply actually had the name instead of the astericks, so I was able to cut and paste...


thanks
jasper