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2013 SRX4
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7 Posts
Discussion Starter #1
I live in northern Illinois and over the last winter, my 2006 CTS started making a whoooooing sound when it's cold. It goes away after it warms up. It doesn't appear to be related to the engine RPM, but it happens when I decelerate and the tranny downshifts. Transmission fluid is at 50%. When should it be changed, since I can't see any dipstick to check it? Wife said the car stopped funny a couple days ago, said she had to press real hard on the brakes to stop. Could the noise be coming from the booster on the master cylinder? Looking for things to check.
 

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2006 3.6L CTS, Hotchkis Sway Bars, FE2
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I live in northern Illinois and over the last winter, my 2006 CTS started making a whoooooing sound when it's cold. It goes away after it warms up. It doesn't appear to be related to the engine RPM, but it happens when I decelerate and the tranny downshifts. Transmission fluid is at 50%. When should it be changed, since I can't see any dipstick to check it? Wife said the car stopped funny a couple days ago, said she had to press real hard on the brakes to stop. Could the noise be coming from the booster on the master cylinder? Looking for things to check.
The only way to check the fluid in the trans is to remove the fill plug while the car is running. Some transmission fluid will drain because of the change in pressure but it'll stop shortly. After that you then add transmission fluid till it starts to drip out of the fill hole. If it happens almost immediately, then your trans is full. However if you've never checked the fluid in your trans or had it replaced in the time that you've owned it, you'd be better off just having the fluid changed and maybe even replace the filter while you're at it. If you decide to check the fluid yourself, the fill plug must be removed and reinstalled while the car is running. If not you can expect to lose quite a bit of fluid and warm or possibly hot transmission fluid is not something you want sprayed all over you.

If she had to press real hard on the brakes then it might be a good idea to check the brake fluid reservoir. If it looks low or is really dirty, changing the fluid might help.

It'll really help to know how many miles your car has and a brief description of your maintenance habits. The master cylinder is separate from the motor so if it only makes the sound when the engine is running, then I would check the vacuum line running from the brake booster to the intake and then possibly the serpentine belt.

I know the power steering pump makes a pretty audible whine if it's low on fluid or the pump is on it's way out. It could also be one of your belts or pulleys or belt tensioners that are bad.
 

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2013 SRX4
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Discussion Starter #3
Sorry about that. She's got 112K miles. I bought it used at around 54K. I keep up with routine maintenance religiously on my cars. I haven't had a car go under 225K miles in the last 20 years. I have no idea how many miles are on the fluid. I was curious as to what mileage it should be changed. I know I should probably trust the computer, but I've never let the tranny fluid in my car get this many miles on it without changing it. Having no dipstick makes it worse, since I can't even see what i

As for the whoooing sound, I'll check out the things you mentioned later this week.
 

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2006 3.6L CTS, Hotchkis Sway Bars, FE2
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Sorry about that. She's got 112K miles. I bought it used at around 54K. I keep up with routine maintenance religiously on my cars. I haven't had a car go under 225K miles in the last 20 years. I have no idea how many miles are on the fluid. I was curious as to what mileage it should be changed. I know I should probably trust the computer, but I've never let the tranny fluid in my car get this many miles on it without changing it. Having no dipstick makes it worse, since I can't even see what i

As for the whoooing sound, I'll check out the things you mentioned later this week.
For safe measure I would just replace all the fluids. Mechanically these cars are great but only if you follow a maintenance schedule religiously. Trans fluid is stated to last 100k but 50k intervals is much better. Trans failure is common on these cars if you let the fluid go to long or if coolant gets in the trans. Engine oil should be changed every 3 to 5k and you should check the fluid level every time you go to start the car. It should always be full but these cars have a habit of drinking oil, thats why it's important to check. Rear diff is typically pretty whiney, but regular fluid changes at 15 to 20k is recommended. In other words, if you want the car to last, change the fluids as much as possible and top the fluids off every chance you get.
 

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2013 SRX4
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Discussion Starter #6
Yeah. I checked it when I replaced the plugs, along with the master cylinder and brake lines. I'll just get the tranny fluid changed when I have them replace the shocks in a couple weeks.
 
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