Chevrolet Cruze Forums banner

1 - 20 of 31 Posts

·
Premium Member
2014 Cruze Diesel, 2007 Cobalt, 1981 Camaro Z28, 2017 Volt
Joined
·
4,410 Posts
Discussion Starter #1 (Edited)
This is the best way I can describe it, at least. Seems to be when you're slowing down gradually, it'll be a kind of hollow "clunk" noise, once, just in front of the driver footwell (or so). Then generally it will do it a second time right as you're stopping. This doesn't happen every time, but it certainly was something I heard this morning, while my wife was driving into work, and I have heard it before (I believe prior to the Trifecta tune, though perhaps not).

Of course, when I had my camera recording, it chose not to do it. When we leave work here in a couple hours, I'll try and get a recording of it. Since I'm not driving, I can't see if it truly is when a downshift occurs or not, but I'll try and keep an eye on the tach.

Anyone have something similar to this happening?
 

·
Premium Member
2014 Cruze Diesel, 2007 Cobalt, 1981 Camaro Z28, 2017 Volt
Joined
·
4,410 Posts
Discussion Starter #2
Bit more info from the drive home, in a bit more traffic, and watching the tach (and speedo). The clunk that occurs just as you're coming to a stop happens right around 5 mph and you can watch the tach pop up a tiny bit just as it does that.

The other thing it does that is around 25 mph or so, and we found out it'll do it multiple times if you accelerate, then let off, then get back on the throttle again, all in a short period of time - typical to city traffic (and people who cannot drive). The tach jumps up and down considerably when that happens.

I did get a video, so I will upload that here soon. You can see the tach, the digital speed reading and you can absolutely hear it (a bit louder than in real life, but all the better for diagnosis).
 

·
Premium Member
2014 Cruze Diesel, 2007 Cobalt, 1981 Camaro Z28, 2017 Volt
Joined
·
4,410 Posts
Discussion Starter #3
 

·
Registered
Joined
·
951 Posts
That seems to be the Torque converter lock-up kicking in and out. Are you running the original fluid, and if so how many miles. It is not really a lifetime fill as the manual might suggest, I would not go more than 50K on that fluid, and if you have not changed it, that is first thing I'd do, as it could make the engage and release of the torque converter lock more harsh just by old, thin and worn out fluid in the transmission.
 

·
Registered
Joined
·
951 Posts
At one point I had 2 Gen 1 Diesels, the second one I bought used with 45K miles that were put on the car in 10 months by the prior owner. It did something similar to your video and had some odd shift behavior, especially compared to my other much lower miles car with the same power train. I did the fluid replacement per the DIY section, using the Amsoil and it was massively improved. I ended up trading that car for the Gen 2 my wife now has, she never liked the used car, mostly because it had a bit of residual smoker smell to it, but otherwise it was a good car.
 

·
Premium Member
2014 Cruze Diesel, 2007 Cobalt, 1981 Camaro Z28, 2017 Volt
Joined
·
4,410 Posts
Discussion Starter #6
Car is running AMSOIL fluid in there...did that back in January of 2018 (at around 71k miles), and then had to do the trans lines a couple months (and 3000 miles later), so a little bit more AMSOIL into there after that. Roughly around 103-104k miles now.

Oddly enough, ever since then, the trans has not been great. This just seems to be the next thing in that list.

But yes, I was thinking torque converter lock/unlock, since I know this trans like to lock the converter up a good amount more than most autos seem to.
 

·
Registered
Joined
·
5 Posts
Just read this and even before I read the others reply I was going to suggest changing the transmission oil. MIne does the same thing. If you coast to a stop you will notice it more than braking quickly to stop. One day I decelerated with the transmission in manual mode, it seems the shift from 4 to 3 hits a bit hard. Remember the diesel is a fairly high compression engine. Changing the trans fluid did help but it does not seem as smooth as it was when it was new. Another comforting thing too is that my changed trans fluid did not have any metal in it. Metal in it would have indicated a real problem brewing. In summary this is just the way this transmission downshifts. So get the fluid changed, it will be better, and don't worry too much about it.
 

·
Premium Member
2014 Cruze Diesel, 2007 Cobalt, 1981 Camaro Z28, 2017 Volt
Joined
·
4,410 Posts
Discussion Starter #8
The fluid only has about 30k miles and about two years on it, and it is Amsoil...shouldn't be needing replacement just yet...

I bought some Race Ramps wheel cribs so I can get the car up, but level (without using stands), and get the aeroshield off and make sure those stupid lines aren't leaking again.
 

·
Premium Member
2014 Cruze Diesel, 2007 Cobalt, 1981 Camaro Z28, 2017 Volt
Joined
·
4,410 Posts
Discussion Starter #10
Yeah, this seems to be present cold or warm. It seems to occasionally be louder if it is colder out, so, that's great.

When I do my oil change in the near future, I'll be pulling the belly pan and checking the trans fluid level. It's been a couple years (and 35k miles) since I did it last anyway, so it's worth checking. Moreso to make sure these stupid trans lines aren't leaking again. I have the old ones, which I'd do the $5 mod on and reinstall, though I'd rather not because that process suckkkkks.
 

·
Premium Member
2014 Cruze Diesel, 2007 Cobalt, 1981 Camaro Z28, 2017 Volt
Joined
·
4,410 Posts
Discussion Starter #11
I checked the trans fluid when I did my oil change on Saturday (and added the specified 0.5qt after closing up the check plug), and found there to be no change in this - still does the clunk noise when the TC locks or unlocks. It drives fine, it's just annoying.

Something else is amiss inside the trans, it would appear. Solenoid or something.
 

·
Premium Member
2014 Cruze Diesel, 2007 Cobalt, 1981 Camaro Z28, 2017 Volt
Joined
·
4,410 Posts
Discussion Starter #12
So just to update this, as I'm not sure if I had made these observations before, or if this is newer behavior:

We park the car in the driveway, and obviously back it out onto the street to get going somewhere. When you shift from park to drive, it does the click/clunk noise. Then, as you are backing up onto the street, slowing down for the gear change to drive, it'll make the noise again, just before you stop. Then it makes the noise again when you shift into drive.

It seems like it's gotten louder, but that may very well be from it being warmer out now and me having the windows down.
 

·
Premium Member
2014 Cruze Diesel, 2007 Cobalt, 1981 Camaro Z28, 2017 Volt
Joined
·
4,410 Posts
Discussion Starter #14
Last time I was under the car (few months ago) I didn't see anything, but that's a good thought. I'm not even really sure what the transmission mounting scheme is on these things...
 

·
Premium Member
2014 Cruze Diesel, 2007 Cobalt, 1981 Camaro Z28, 2017 Volt
Joined
·
4,410 Posts
Discussion Starter #15
I took a peek at the mounts, and they all seemed to be good (from what I could see from the engine bay - which isn't much - at least).

However, today, since my wife was leaving, I popped the hood, and had her shift back and forth between Drive and Reverse with her foot on the brake, so I could listen for the sound and see if maybe I could spot a source.

Well, I can certainly say it isn't coming from the engine bay. Where does it seem to be the most "sharp"/loud? The center of the **** wheel. And out by the wheel. Definitely does not seem further inboard, closer to the transmission. So the transmission may not be the culprit, it's just tied to certain shifts (Park to Drive, Drive to Reverse, Park to Reverse, nearing a stop, and any time you get on and off the gas in 4th gear).

When the vehicle completes its shift, and you see the car's weight shift a bit from said shift (working against the brakes), that's when it pops/snaps.
 

·
Registered
Joined
·
330 Posts
I took a peek at the mounts, and they all seemed to be good (from what I could see from the engine bay - which isn't much - at least).

However, today, since my wife was leaving, I popped the hood, and had her shift back and forth between Drive and Reverse with her foot on the brake, so I could listen for the sound and see if maybe I could spot a source.

Well, I can certainly say it isn't coming from the engine bay. Where does it seem to be the most "sharp"/loud? The center of the **** wheel. And out by the wheel. Definitely does not seem further inboard, closer to the transmission. So the transmission may not be the culprit, it's just tied to certain shifts (Park to Drive, Drive to Reverse, Park to Reverse, nearing a stop, and any time you get on and off the gas in 4th gear).

When the vehicle completes its shift, and you see the car's weight shift a bit from said shift (working against the brakes), that's when it pops/snaps.
How do your rotors look? Last time you messed with the brakes?
 

·
Premium Member
2014 Cruze Diesel, 2007 Cobalt, 1981 Camaro Z28, 2017 Volt
Joined
·
4,410 Posts
Discussion Starter #17
Did pads and rotors back in mid-October, so they're nice and fresh.
 

·
Reverend Red Bull
Joined
·
1,058 Posts
I took a peek at the mounts, and they all seemed to be good (from what I could see from the engine bay - which isn't much - at least).

However, today, since my wife was leaving, I popped the hood, and had her shift back and forth between Drive and Reverse with her foot on the brake, so I could listen for the sound and see if maybe I could spot a source.

Well, I can certainly say it isn't coming from the engine bay. Where does it seem to be the most "sharp"/loud? The center of the **** wheel. And out by the wheel. Definitely does not seem further inboard, closer to the transmission. So the transmission may not be the culprit, it's just tied to certain shifts (Park to Drive, Drive to Reverse, Park to Reverse, nearing a stop, and any time you get on and off the gas in 4th gear).

When the vehicle completes its shift, and you see the car's weight shift a bit from said shift (working against the brakes), that's when it pops/snaps.
I'd take a real close look at the CV joints if you haven't done that yet.
 

·
Registered
Joined
·
965 Posts
Where does it seem to be the most "sharp"/loud? The center of the **** wheel. And out by the wheel.
I've learned, on the Impalas, the fix for this is to lube the splines on the axle where it goes thru the hub. A good amount.

The necessary amount for lubrication isn't great, but to deaden the clunk, put as much on as you can without it oozing all over your driveway :)

Doug

.
 

·
Registered
Joined
·
373 Posts
Check your a arms, wheel bearing.

Get that wheel off the ground and see if can duplicate the sound by applying force in different directions with a 2x4 (be careful not to damage the car)
 
1 - 20 of 31 Posts
Top