My cobalt Lt 5spd has started to develope a sort of rattle like a worn gear chatter or just a general chatter as you accelerate at low RPM's in 1st gear and when you change to 2nd gear in the 800-1600rpm 1st gear range and 1000-1700 second gear range and really now whenever you accelerate at lower rpms. its not a spark knock, its just like if you selected the wrong gear like turning 500rpm or less in 3rd gear you hear the gears being pissed off. the car just turned 5000k, no racing, brought the rpm's up to 5500 a few times and churped second while test driving with friends, but granny shifted always and just a daily driver. I have been reading alot about bad tranny's and clutches.. should i be concerned as a tranny issue or I also read about a timing chain issue that maybe i am hearing it rattle when the rpm is very low under load? also, seems to shift fine although lately i have had some issues getting into 1st at a dead stop, and I get the annoying sqweek from the clutch pedel when you turn right or left and engage the clutch, not all the time, usually only when it rains outside. Any help would be great. Oh yea its a non supercharged motor. Thanks in advance guys!

 

Any Thoughts?

 

It sounds like a warranty issue. I've heard of people bringing thier cars in for a lot less than that. Just explain to them what it is doing, and leave out the part of speed shifting and chirping 2nd!

 

Gear rattle happens. My LT's trans always rattles when lugging it around. Anything below 1,200 rpm under load is when its most noticeable. I've got close to 17k on her now with no problems. Its also hard to get the trans into first at a stop sometimes. One thing that I believe helped was switching to a synthetic fluid inside the trans. I went with royal purple ATF.

However, I gave up on just shfting into first and started going into 4th, then shifting into 1st before taking off. I know it -shouldn't- be that way but it really doesn't matter to me so long as the transmission still works.

 

Malaclypse, where is the refill and drain plug on the trans? I to also want to put a better fluid in the trans case...

 

Selecting first is sometimes difficult on mine too. My O/M even refers to it and said something like put transmission in neutral, release and then press down on the clutch pedal and retry first. I don't worry about it. My old M/T cars also did the same thing occasionally.

 

When I had my Cavalier Z24 I noticed that after the the first 30,000 miles or so I had developed gear noise, especially noticable in first and when in low RPMs especially second. I traded the car in on my SS, but it had 100,000 and still ran strong gear noise and all and had basically the same tranny. I also had occasional problems going into first, and usually just went into neutral then tried it again like samesun said and that usually worked fine. I usually I'm sure this is probably just typical for these transmissions. Unless you notice slipping, grinding or other problems I wouldn't worry too much.

 

Both drain and fill plugs are on the driver side of the car. The drain plug is at the bottom of the diff housing. The fill plug is about 3" up and to the left from the drain. They'll look the same and they both require an allen wrench to remove them. P.S. I think those plugs are torqued to sixty-two thousand ft/lbs from the factory.

 

Awsome thanks for the location.. What fluid did you add in yours? Royal Purple Sythetic ATF?

 

Yeah. I went with Royal Purple ATF. Might switch that out for GM Synchromesh after I do some more investigating for compatability.

 

I am Having The exact same problem with my 2.2. Started at 200 miles out of warranty. Its very loud at low rpm shifting into 1st and 2nd and sounds like its coming from the tranny area although im having trouble pinpointing the rattle. Any help would be greatly appreciated.

 

mine has it too, i have royal purple syncromax in it, it helped a bit and shifts better when first getting in the car for the day. the noise seems to be effected alot with weather, humidity and all that