Chevy auto trans problem

[2x4]

2009 Chevy 2500 6.0 liter, automatic transmission. Pulling long steep hill yesterday 6 miles from home & front end started shaking like flat tire. Pulled off & smoke rolling from under hood, trans. fluid leaking down on exhaust pipe. Prolly overflowing where fill tube enters trans. Stick showed overfull by a lot. Going downhill & level the leak didn't seem to hit exhaust pipe. Made it home ok after immediately turning around. When cold today, stick shows 2 inches above COLD full mark. When hot stick showed 4 inches above full HOT mark. Idling in driveway in PARK there is a whistling sound, then a squealing like a belt squealing but its not an engine belt & leak continues. Trans oil smells like cow poop when hot but don't know what it smelled like before. Newly opened bottle of trans. fluid smells about the same. Front end never shook any more on the way home at 55 mph. Beforehand stick always showed correct level hot or cold. What in the world is wrong? Never happened to any automatic I've ever driven before.

 

[rustred]

I would say your goose is cooked ! Oops trans. The fluid level will be high when not running due to the pump not pumping the oil. Once running the level drops to the full mark. And if the oil is brown and stinks it’s burnt. Should be red with just a slight oil smell if you know what trans oil smells like. It’s hard to say as the converter may be loose on the flex plate. Or the pump is shot , is my guess . And hard to tell without eyes and hands and feet being there.

 

[2x4]

I would say your goose is cooked ! Oops trans. The fluid level will be high when not running due to the pump not pumping the oil. Once running the level drops to the full mark. And if the oil is brown and stinks it’s burnt. Should be red with just a slight oil smell if you know what trans oil smells like. It’s hard to say as the converter may be loose on the flex plate. Or the pump is shot , is my guess . And hard to tell without eyes and hands and feet being there.

In your experience what might be best? Buy new, buy rebuilt, buy used or have it rebuilt. A long time transmission shop is 30 miles away.

 

[jimg.allentown]

In your experience what might be best? Buy new, buy rebuilt, buy used or have it rebuilt. A long time transmission shop is 30 miles away.

Best would be to find out where the extra oil came from. Or was it oil? Could it be coolant from a leaking trans cooler in the radiator? That might cause some funny noises and smells as well as an overfull transmission.
Either way, you need to do some diagnosis. I would start by removing the transmission oil pan to see what's in it. If it is coolant, you might get away with replacing the radiator and a transmission oil change.

 

[rustred]

In your experience what might be best? Buy new, buy rebuilt, buy used or have it rebuilt. A long time transmission shop is 30 miles away.

My view on it. If it’s the trans get a used one from an auto wrecker. Would be less than 1K. Vs a rebuild for 5 k , my view. Used ones have a 3 month warranty here at least. Vs a year on a rebuild. U need an expert on this for proper diagnosis.

 

[used red MN]

Please clarify, were the after the episode fluid checks when back home done with it idling or was the engine off? Auto trans fluids are almost always checked with the engine running. You also have to sort of learn how to “read” trans fluid on the dipstick. It is easy to misread fluid you drag up in the tube when you pull the stick out if you do the pull stick wipe a check sequence. If it was running I’d say it probably is not filling the torque converter properly. Not sure what that means. Older transmissions like the 350/400 used to fill the converter then the fluid out of the converter went to the cooler. What you thought was the front end shaking was very likely what is called a “shudder” from a clutch pack in the trans trying to hold but slipping and going between holding and slipping very quickly. If you are not pulling the trans yourself I definitely would get it towed or haul it on a trailer to where it will be repaired.

 

[2x4]

both when hot then later when cold. Neighbor with much Chevy tranny experience read it too.

My view on it. If it’s the trans get a used one from an auto wrecker. Would be less than 1K. Vs a rebuild for 5 k , my view. Used ones have a 3 month warranty here at least. Vs a year on a rebuild. U need an expert on this for proper diagnosis.

Best would be to find out where the extra oil came from. Or was it oil? Could it be coolant from a leaking trans cooler in the radiator? That might cause some funny noises and smells as well as an overfull transmission.
Either way, you need to do some diagnosis. I would start by removing the transmission oil pan to see what's in it. If it is coolant, you might get away with replacing the radiator and a transmission oil change.

coolant has been disappearing regularly & added a gallon to plastic reservoir tonite & it disappeared too. Truck wasn't running when I added the gallon.

 

[used red MN]

coolant has been disappearing regularly & added a gallon to plastic reservoir tonite & it disappeared too. Truck wasn't running when I added the gallon.

I’m not sure if the coolers on these newer trucks are the type that set in the end tank on the radiator or if they are a separate cooler that exchanges the heat directly to air. I would think if you got even a pint of coolant passed into the trans through the cooler the fluid would look milky.

 

[2x4]

I’m not sure if the coolers on these newer trucks are the type that set in the end tank on the radiator or if they are a separate cooler that exchanges the heat directly to air. I would think if you got even a pint of coolant passed into the trans through the cooler the fluid would look milky.

no milky appearance with many checks by me & neighbor.

 

[rustred]

So what did neighbor think??

 

[BarnyardEngineering]

Does this "long time transmission shop" have a history of steering people wrong? If not, I would take it there and let them figure it out. They are capable of diagnosing and dealing with more than just the transmission unit itself. If the transmission cooler is the problem and it's integral to the radiator, they can change that.

 

[miangus]

I think it is time for a replacement. I would try installing a separate cooler if I expected the coolant was getting in the transmission. I have seen that happen. Change the oil, run it a bit and change again. If it wasn't slipping it maybe ok. If it starts slipping even a little bit in reverse start shopping for a replacement. Were you watching the trans temp gauge? I am assuming with the 6 liter you have an HD 2500 with the 80 series, if you have a 1500 with the 60 series I expect it's toast.

 

[Mule Meat]

Bad torque converter.

 

[Brown David]

Another vote for a ruptured cooler letting coolant into the transmission.

I've encountered this a few times.

 

[DoubleO7]

My view on it. If it’s the trans get a used one from an auto wrecker. Would be less than 1K. Vs a rebuild for 5 k , my view. Used ones have a 3 month warranty here at least. Vs a year on a rebuild. U need an expert on this for proper diagnosis.

WOW, down here you would be extremely lucky to find a salvage yard tranny for this truck for less than $1300. Average is around $2000. From "reputable" yards that might offer a warranty. Just the core price is anywhere from $700 to $1200 when buying a rebuilt.

 

[DoubleO7]

Is not transmission oil psi in the external lines usually more psi than the water in the rad?
I have seen way more oil in the rad from a tranny and or engine than ever in the tranny due to internal cooler leaks.

 

[miangus]

Is not transmission oil psi in the external lines usually more psi than the water in the rad?
I have seen way more oil in the rad from a tranny and or engine than ever in the tranny due to internal cooler leaks.

It may happen when the truck is shut off and the radiator still has pressure. But I have seen it happen.

 

[Brown David]

Is not transmission oil psi in the external lines usually more psi than the water in the rad?
I have seen way more oil in the rad from a tranny and or engine than ever in the tranny due to internal cooler leaks.

Regardless of pressure difference it will mix usually resulting in trans. failure.