QuestionQUESTION: I know you answer regarding ford, but thought I would take a shot in asking you about my sons truck. Last night, he pulled out of a store and he heard a loud clicking/popping noise coming from the rear. He put it in reverse and the sound got louder. I went to pick him up, my dh drove the truck home but couldnt get the truck over 10mph because clicking/popping became louder. It sounds as if the sound disappears for a bit, then all at once it gets loud.. It almost sounds like a machine gun but not as loud of course. We got it home, my dh got out of the truck after placing the truck in park and it began to roll forward, even being in Park??? Can you guess at what my cause this?? Please help us...
ANSWER: sounds to me like theres something wrong with the transmission, possibly a gear issue. Did he not want to go over 10 or was he unable to go over 10? If thje vehicle would not go over 10 then it could be a VSS(vehicle speed sensor) grounding out on the output shaft causing the noise, and since the VSS isn't properly sending the vehicle speed to the PCM, the PCM thinks the vehicle is traveling at low speed or not at all, thus not allowing the transmission shift solenoid, to shift into the next gear.
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QUESTION: No, it will go over 10, just slowed because when we got above 10 the noise would get louder.
ANSWER: oh then i doubt its the VSS. I googled this and all i could seem to find was issues with the front ball joints wearing out, and making the noise. if the ball joints are good, I'll have to ask my auto teacher about this. I am going to need more info on the vehicle.
Model:
Mileage:
What size engine:
Did your son go off0roading that day or anything extreme that might have caused this:
but i wont be able to talk to him untill tuesday.
I'll keep looking on google and other sites i know of.
If you would like my e-mail is corymumm@bellsouth.net you can email me pics of where the sound is comming from, and the driveline itself. and ill be able to try and help you out a bit further from the pics, and i can try to determine whats going on. But dont worry I wont give up on you guys. Just email me a few pics if you can or we can email back and fourth about this so you can get a quicker response,and possibly a quicker solution.
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QUESTION: 98 Chevy Z71 4x4- 135,000 miles, 350 vtec - yes he frequently visits mud! But not that very day, however more than a week ago, he took a challenge and went into a very ugly hole... the truck buried so deep that he had to wench it out.. I dont have pics... sorry
AnswerAllrighty I'll be able to look more into this for you, and as soon as I find out more I'll let you know.
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Ok I search google, and I found a page on yahoo that has answers about this, that person had the same exact problem(unless you posted on yahoo also).
But some of the responses were:
"
If the truck started rolling, and making that sound even though it was in Park, I would suspect a broken Park Pawl. The park pawl is a piece in the transmission that locks or latches the gears so the truck won't move when in Park. This may have broken and the broken piece is loose inside the transmission, and making the machine gun noise. To avoid any further damage to the transmission, have it towed (don't drive it) to a transmission shop or the car dealer for repair.
The park pawl is subject to damage from:
1. Parking the truck on a slope or hill and not setting the parking brake BEFORE shifting into Park. This causes the park pawl to hold the full weight of the truck from rolling down the hill. It usually is fairly difficult to pull the truck out of Park, and it makes a loud clunk sound when you do jerk it out of park.
2. The park pawl is also damaged when the truck is shifted into Park before the truck has come to a complete stop. Even while rolling a couple of miles an hour and shifting into park will cause it to break.
3. Those concrete parking lot bumpers are another cause........ if you pull up tight to them, putting the tires against them with some pressure, and then shift into Park, the park pawl will have a great deal of pressure put on it and will be difficult to pull out of park, and make that big clunk sound when you do ( like in #1)
When you stop and are going to put the truck in Park, always hold your foot on the foot brake.... then set the parking brake.....and then shift it into Park."
"If the noise is coming from the rear it may be in the rear end, maybe a chipped ring or pinion, or even just the bearing in the front seal is out. This would also explain the rolling, because even if you put it in park and the rear end won't hold it will roll"
Check those things out, I'm going to look for more info on that parking pawl, a bit more.
But I'm going to need the following:
Vehicle model: (ex. Silvarado 1500)
Engine size:(ex. V8 5.7L FI)
But the more I read about that parking pawl the more I think that could be the problem. Good Luck. Ill keep looking.
