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Discussion Starter #1
In the morning when I fire up the car and start driving heading to work, I hear a rattle or thump, almost a light knocking sound. It seems it is coming from the suspension, possibly strut or maybe control arm. However, once the car warms up I don't hear it any more.

Any ideas?
 

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I have the same issue. Desperately looking for the source of the noise. I will be putting my Cobalt on the jack stands soon, to thoroghly check, the under pinnings.
I will be checking ball joints, tie rod ends, swing arms, steering knuckles, struts, strut top hats, and anything I might have left out, related to the front suspension.
I will post my findings, afterwords.
If you figure it out, please post it here.
Thanks
james
 

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Well these are notorious for saddle bushings and later on control ARM pancake bushings...Check those first.
 

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With your mileage it is probably saddle bushings. If you can see daylight between rubber and swaybar they're done. One guy on here could even move his swaybar side to side. If you wait too long it will destroy the end-links. As far as pancake bushing in control ARM rubber will start to separate from outside ring but won't make noise until they completely separate.
 

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Discussion Starter #6
With your mileage it is probably saddle bushings. If you can see daylight between rubber and swaybar they're done. One guy on here could even move his swaybar side to side. If you wait too long it will destroy the end-links. As far as pancake bushing in control ARM rubber will start to separate from outside ring but won't make noise until they completely separate.
Thanks for the info...

My friend who is a suspension guru and I will get it up int he air and looked at, if they're worn or beat I will get a new set.... was thinking of redoing the control arms anyway... so might as well get everything I can done to it.

Seafoamed it tonight int he gas tank and going to do the crank tomorrow as well, but the rattling noise gets on my nerves in the morning and it has go to go.
 

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Washington probably gets cool enough in the morning to stiffen rubber of saddle bushings so if there is a bit of play there it will make noise until rubber softens up.
 

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Discussion Starter #8
Well, we had the car up int he air and sure enough the bushings are bad. I won't say toast, but worn enough to cause the rattle.

I ordered two new LCAs and I also ordered a pair of Moog Bushings, since they seem to be a lot better in quality.
 

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Yeah, I was shocked at how low they were on eBay.... That is where I ordered them from got the Moog Bushing from Local store.

I should get them installed Next week as I expect they will probably arrive on Wed or Thursday at the latest.

Got an off topic question for you...

Is it possible to re-gear the 5 speed manual. at 70-75 that thing almost runs 3,000 RPMS and I want it to be closer to 2250-2500
 

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Now you know why 150 MPH is pretty much impossible with these.

I know gearing is different between regular SS and TC or SC but I don't know if they make sets for different ratios like the old Chevys. I know some guys oversize their tires and get their speedometer recalibrated.

Even the automatic that we have is gear to slow.

---------- Post added at 11:46 PM ---------- Previous post was at 11:39 PM ----------

Let me know how those Lower control arms turn out, because I have them in my wish list for next spring.
 

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Discussion Starter #12
Well definitely not trying to get to 150, but If I could re-gaer fifth, it would cut down on RPMs thus hopefully increasing Gas Mileage even more. I just think 3000 rpms is a bit high for 75 mph, and that is what I normally drive since I have a killer commute.

Not complaining as I am averaging 35+, and on the instant sometimes it is reading 45+, but I know those can be off +/- 3mpgs (inst screen)

But 60 miles each way of 3000 RPMS for an hour straight can't be good for wear and tear on a motor either. I got her running nice right now, but a few tweaks and she could purr even better. Not trying to Fast and Furious it out, just make it more economical and less wear and tear on the powertrain.

Also, will do on the LCAs. if they come in Wed they go in Friday, if Thursday they go in Saturday. that is also providing my Moog Bushings are in too.
 

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You will be lucky to get them this week with the holidays.

I agree with your theory on the RPM's of these little engines but a 4 cylinder has to rev to get horsepower and it might be some sort of compromise. I noticed the 2012 Cruze has 10% less rev's than the 2011 model. Maybe they're taking baby steps to keep oil companies happy and the government happy at same time.

My autoCobalt is reving at 2200rpm at 60mph with torq locked up.
 

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Discussion Starter #16
It's not, but at 3,000 RPMs your pretty much keeping the fuel delivery at a much higher rate than if you did 2500 or 2000.

UPDATE: LCAs are in, as well as upper strut mounts and the noise is gone.
 

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Is the quality of LCA as good as the picture leads us to believe. And you say upper strut mounts??? I tought you said saddle bushings.
 

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Discussion Starter #18
Well the Bushings are already in the LCA but we decided to replace the upper strut mounts too... because they were worn, and BAM the car drives very nice, smooth and no more rattle.

The quality is about the same as what the factory ones are, but the bushing was a full rubber as opposed to the slotted OEM
 

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The quality is about the same as what the factory ones are, but the bushing was a full rubber as opposed to the slotted OEM

OK so not like picture. I was going to order those and switch the bushing for a full one so now I won't have to. Thanks a lot...

But they are cast aluminum right?
 

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Discussion Starter #20
Yes, cast aluminum.

---------- Post added at 09:34 PM ---------- Previous post was at 09:28 PM ----------

GM must use a very cheap rubber compound as the Bushings looked like they had dry rot.
 
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