Vehicle: 2009 Chevy HHR 2.2L LS Automatic 4T45E 3.63 Trans
Odometer: 272,000 miles original motor and trans
Symptoms: Transmission Slippage, ATF Leak, ATF odor through cabin vents, Oxidized ATF (Brown Fluid), No CEL codes.
Procedure/Observations: Upon experiencing initial slippage, dropped transmission pan and observed brown fluid perhaps suggesting oxygen contamination and/or overheating of transmission. I then flushed the system, replaced ATF and filter/gasket. Observed ~1mm thickness of fine transmission particles on pan magnet. I concluded that this was within normal range of wear. The filter also did not possess any metallic material other than a very fine powder.
Notes: Concluding that worn fluid in combination with perhaps a clogged filter may cause slippage through inadequate ATF pressure, my initial course of action was to replace fluid with fresh ATF and replace filter along with new pan gasket. However, the worn fluid was brown in color indicating that there was a leak in the system and/or the system was overheating. The fluid that was flushed from the system was exactly 5.43 quarts of the 10.60 quarts that should have been in the system. Note that I used a professional fluid exchange machine so as not to leave residual worn ATF in system and to obtain the accurate fluid level.
Results: Slippage disappeared for several hundred miles however ATF smell remained and began to slip thereafter. Clearly, a leak is present and when enough fluid has left the system, it cannot properly maintain adequate internal pressure.
Pinpointing the Leak: I will be removing the pan again to inspect fluid and pan magnet for new metallic particles if present. If presence of large metallic particles is positive, then internal damage is likely and overhaul required. If presence of large metallic particles is negative, I will then determine if the leak is possibly external the transaxle by checking:
a) CV axle seals
b) Cooler Lines/Fittings
c) Leak at sensor
If leak is not external, it must therefore be internal. From what can be observed to date, the evidence suggests to me that an internal seal has failed allowing fluid to leak out of the system.

I will continue to update this post and if a complete transmission rebuild is required (more than likely), I will post detailed information, steps, and pictures for the rebuild process once I am finished.

Like oil, the transmission fluid along with the filter should be replaced regularly at 25,000 mile intervals. Failure to do so will inevitably create worn fluid, a high probability of clogging the filter, overheating, leaks, and eventual internal transmission problems. Changing the ATF and filter on our HHR's is as easy as doing an oil change. Preventative maintenance is key and if slippage occurs then the vehicle should immediately be parked and not be driven to prevent internal transmission damage. The longer you let the maintenance "slip" at the first signs of trouble it will create much bigger and expensive problems in the not so distant future.

 

Uh...No. Wrong.
This may be your personal belief but trying to post up incorrect info for others to follow is just wrong.

 

Idk man 25,000-30,000 is pretty standard, maybe a little more with Royal Purple.

 

Dexron VI is full syn and is rated "lifetime" under normal conditions. 50,000 miles under extreme conditions, like taxicabs.

Why not just locate and fix the leak?

From page 6-6 of your 2009 Owner Manual.

 

It’s your preference, I change mine every 250,000 klms or 150,000 miles , which is my preference.
It is fairly easy to drop the pan an change the fluid and filter but every 25,000 miles in synthetic fluid is a waste, of fluid, filter and money. Just my opinion .

 

Nice I was wrong you were right you're the man, when is a good day that I can sign the title of my HHR over to you?

I'll make sure not to flood the forums with my stupidity ever again.

 

MY HHR had a tranny fluid change at 40K, then 178K, and is still churning that fluid at 215K and forward. Even the "stealership" suggested 40K intervals. For me that would be once per year which is honestly overkill. We are all offering our personal input, much like you are. You can change the fluid at 2K, 20K, 150K, or more, but I am willing to bet you would find no difference between fluid drained at 25K vs 150K. Its just hydraulic fluid, after all. Its your money and time, man.

 

Touchy!

The dealership is out for your money, just like any other shop. They recommend oil changes every 3,000 mile regardless of the manufacturers recommendation (when the Oil Life Monitor says to), not to mention Power steering fluid flushes and ATF flushes (that GM recommends against).

They recommend a lot of services that GM warns against! That is why they give you an Owner Manual, so you can make your own decisions.

Brown fluid is bad, I would suspect a pin hole in the cooler.

It usually turns black in short order. Some shops will pull the dipstick and show you it is black as proof that you need to give them $150 to flush it.

I had a Toyota Pickup that came with lifetime oil changes. The Owner Manual said every 5,000 miles. The shop demanded that I come in every 3,000 miles or they would void the contract. I was driving more than 1,000 miles a week. Go figure.

 

I wasn’t intending to upset you, just explain my preferences and your preference, I did not say anything about your intelligence nor who was right or wrong.