: weird noise on hard acceleration



B1n2fra
10-19-12, 07:11 AM
I have a 2007 awd Northstar 1sg and recently under hard acceleration from 0 I get a weird clunking noise as if the gears were skipping or something. I really can't identify where the noise is coming from, 1 moment it's from the front 1 moment it's from the middle. what possibly could be wrong. if I release the gas pedal when I hear the noise it stops and it's only occurs from 0 or a stop when I put the pedal down when I put the pedal down.

DarkMingBlueSTS
10-19-12, 07:18 AM
Transfer case maybe?

truckinman
10-19-12, 07:26 AM
Is it just one initial clunk the second you take off? Or a series of clunks? Bc I'm thinking it could even be a bad or loose front strut, and when you take off and that initial release of weight up front could be causing the strut to move just enough. I'd check the engine mounts too for same scenario.

B1n2fra
10-19-12, 05:47 PM
It's a continuous noise until the car gets going or after I release the gas pedal , it's not really a clunk it's more like gears skipping on each other its kinda hard to describe a noise in words lol.

DarkMingBlueSTS
10-19-12, 06:22 PM
It's a continuous noise until the car gets going or after I release the gas pedal , it's not really a clunk it's more like gears skipping on each other its kinda hard to describe a noise in words lol.

IMO I really think its a transfer case, driveshaft(s), or transmission. I don't really know how these cars are built but down here we build a lot of mud trucks and I've seen some crazy things happen to transfer cases

truckinman
10-19-12, 07:28 PM
IMO I really think its a transfer case, driveshaft(s), or transmission. I don't really know how these cars are built but down here we build a lot of mud trucks and I've seen some crazy things happen to transfer cases

Yea now that I know it's continuous, I agree. I'm all about 4-wheeling jeeps so I know what can happen with drive shafts and what not. T-case sounds like a good culprit. Could be a diff tho too.

DarkMingBlueSTS
10-19-12, 07:39 PM
Yea now that I know it's continuous, I agree. I'm all about 4-wheeling jeeps so I know what can happen with drive shafts and what not. T-case sounds like a good culprit. Could be a diff tho too.

Agreed on the diff

B1n2fra
10-19-12, 08:23 PM
Front or rear differential and is that a very expensive repair

DarkMingBlueSTS
10-19-12, 08:58 PM
Front or rear differential and is that a very expensive repair

Front, I think you said you heard the noise there and in the middle. Idk how much but it will cheaper than a tranny or a transfer case

truckinman
10-19-12, 11:45 PM
Front, I think you said you heard the noise there and in the middle. Idk how much but it will cheaper than a tranny or a transfer case

Could have something to do with the yoke on your front diff. At least that's where the drive shaft hooks to the diff on trucks and jeeps. I don't know tho, does the caddy use a good ol fashion U-joint like trucks to hook the shaft to the yoke? Or is it even called a "yoke" on the caddy? But that could be slipping, causing the drive shaft to make noise at the front and in the middle with the t-case.

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Front or rear differential and is that a very expensive repair

I know in my jeep, if I had someone else do it (which I would fix it myself) but if you paid some one to do it, it would be about 300 ish. But in jeeps and trucks, that's all pretty easy to get too. Especially jeeps with their solid (straight) axles. So I'm sure the caddy would easily be double that.

DarkMingBlueSTS
10-20-12, 12:05 AM
Could have something to do with the yoke on your front diff. At least that's where the drive shaft hooks to the diff on trucks and jeeps. I don't know tho, does the caddy use a good ol fashion U-joint like trucks to hook the shaft to the yoke? Or is it even called a "yoke" on the caddy? But that could be slipping, causing the drive shaft to make noise at the front and in the middle with the t-case.

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Lol I have no idea myself I'm just going on experience with trucks too

I know in my jeep, if I had someone else do it (which I would fix it myself) but if you paid some one to do it, it would be about 300 ish. But in jeeps and trucks, that's all pretty easy to get too. Especially jeeps with their solid (straight) axles. So I'm sure the caddy would easily be double that.

Yup what he said

B1n2fra
10-20-12, 12:24 PM
Just a though... Would it be possible to rip the front differential and drive components out and do away with the awd and make the car rwd. Just a though I love the awd on this car just a pain to fix these problems im experiencing on this car .

DarkMingBlueSTS
10-20-12, 12:39 PM
Probably but you'd have to remove the front drive shaft and maybe even remove some parts out of the front diff

dkozloski
10-20-12, 03:37 PM
The Morse chain is worn out in the transfer case and is jumping teeth. There is a repair kit available through Borg-Warner.

B1n2fra
10-20-12, 03:57 PM
The Morse chain is worn out in the transfer case and is jumping teeth. There is a repair kit available through Borg-Warner.

Has this happened to you before.is this a expensive repair

dkozloski
10-20-12, 04:27 PM
There is another thread on the same subject. It seems to me that you can get the repair kit other than through the dealer and the repair is not outrageous.

B1n2fra
10-20-12, 06:42 PM
There is another thread on the same subject. It seems to me that you can get the repair kit other than through the dealer and the repair is not outrageous.

Do you have a link for it or do you know what the title is.

dkozloski
10-20-12, 09:47 PM
Do you have a link for it or do you know what the title is.I don't remember the details. It might have been in a CTS or SRX thread but it's still the same circumstances.

truckinman
10-20-12, 10:09 PM
Just a though... Would it be possible to rip the front differential and drive components out and do away with the awd and make the car rwd. Just a though I love the awd on this car just a pain to fix these problems im experiencing on this car .

Not a good idea to take out the front components on an AWD car. If it had a selectable 4wd system like trucks do, yes. But not with an automatic AWD system. Your T Case will constantly think your front tires are spinning and you won't have all your power. Happened to my buddy in his Jeep Grand Cherokee with Automatic 4wd. He took out the front drive shaft and he lost a LOT of power bc the computer thought something was wrong.

Ludacrisvp
10-20-12, 11:37 PM
Not a good idea to take out the front components on an AWD car. If it had a selectable 4wd system like trucks do, yes. But not with an automatic AWD system. Your T Case will constantly think your front tires are spinning and you won't have all your power. Happened to my buddy in his Jeep Grand Cherokee with Automatic 4wd. He took out the front drive shaft and he lost a LOT of power bc the computer thought something was wrong.
Then i think the answer would be pull the transfer case out and driveshaft and replace it with the driveshaft for the RWD only model.
If I recall under the car its transmission -> really short shaft -> transfer case -> output front short shaft / output rear meduim length shaft -> front differential / rear differential.
So strip it out to transmission -> standard RWD driveshaft -> rear differential.

Removing transfer case, 3 varied length drive shafts, front differential, front axles?

So since I recall seeing that the 6l50E transmission is used in Trucks, any chance of swapping over the selectable 4WD transfer case?
Likely would never really work but who knows.

dkozloski
10-21-12, 12:13 AM
The STS transfer case is a surprisingly small and compact device. Even at that, there is diminished room for the passenger's feet. If you tried to install an FWD galumpous transfer case you'd have no room at all for a passenger and there is no point to it because under most circumstances the AWD unit works just fine.

truckinman
10-21-12, 12:23 AM
Then i think the answer would be pull the transfer case out and driveshaft and replace it with the driveshaft for the RWD only model.
If I recall under the car its transmission -> really short shaft -> transfer case -> output front short shaft / output rear meduim length shaft -> front differential / rear differential.
So strip it out to transmission -> standard RWD driveshaft -> rear differential.

Removing transfer case, 3 varied length drive shafts, front differential, front axles?

So since I recall seeing that the 6l50E transmission is used in Trucks, any chance of swapping over the selectable 4WD transfer case?
Likely would never really work but who knows.

I'm not sure it would work really. First off, depending how much room is Down there on the STS, I don't know that there would even be enough room for a big selectable T-case from a truck. And second, I'm not sure how you'd get it to work. I know GM likes to use buttons for there selectable systems. So at least there's no mechanical lever to put up thru the floor like in my jeeps. If the T-case fits, and you can wire it up right to select between 4 wheel and two wheel, I guess it'd work. I don't know enough about the Cadillac AWD system to give an educated guess on. Just what I know about them on trucks and jeeps.

B1n2fra
10-23-12, 09:36 PM
There is another thread on the same subject. It seems to me that you can get the repair kit other than through the dealer and the repair is not outrageous.

Thanks.. Found multiple threads and even a youtube video on this transfer case.

Platinum06
11-08-12, 12:13 AM
I had this exact same thing last week in my 07 AWD.
They said it was the drive shaft. Was fixed in 2 hours while i waited.
I video'd it on my Iphone if you need to hear it. It did sound like something was skipping or ratcheting.

B1n2fra
11-08-12, 05:58 PM
I had this exact same thing last week in my 07 AWD.
They said it was the drive shaft. Was fixed in 2 hours while i waited.
I video'd it on my Iphone if you need to hear it. It did sound like something was skipping or ratcheting.

Please post. Dont want to spend money on the wrong thing.

Platinum06
11-09-12, 02:58 PM
http://www.youtube.com/watch?v=DeAgOtmsvvI