Transmission leaking? Have general question

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Shatcher0428

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My 04 suburban with 306k miles on it has started leaking tranny fluid. I am the second owner of the truck and drive it regularly and use it to tow camper. My question is really should I just go ahead and get the transmission rebuilt or just fix the leak? So far knock on wood I have had zero issues with the transmission. I have done engine work to it and normally do all my maintenance but I have not ever done much transmission work. All opinions are welcome!
 

OR VietVet

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Well, the actual leak could be from the bell housing area and blowing back on the pan. If is the bell housing, then could be the torque converter seal and that means pulling transmission. If you like the truck and want to keep and want to keep towing, build it with heavier duty components and flush entire system and if does not have a separate cooler up front, add it.
 

Sam Harris

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first thing I’d suspect, would be the cooler lines. Whether they go to an external cooler, or to the radiator. Also, might be a pan seal leaking. Those would be welcome fixes, as opposed to some other possibilities.
 
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My 04 suburban with 306k miles on it has started leaking tranny fluid. I am the second owner of the truck and drive it regularly and use it to tow camper. My question is really should I just go ahead and get the transmission rebuilt or just fix the leak? So far knock on wood I have had zero issues with the transmission. I have done engine work to it and normally do all my maintenance but I have not ever done much transmission work. All opinions are welcome!
If it’s leaking at the converter seal you’re pulling it out to replace the seal. If it has 300k on it (assuming the trans is original and never been rebuilt or replaced), you may as well take it down and overhaul it.

There’s no point in spending the time to yank it out without giving it a good rebuild as you likely be doing it sooner rather than later. Better that instead of it failing on you at the worst possible time.

Ill post a link to my rebuild video series on the 4l60e here if you plan on tackling it yourself and want some reference material
 

rockola1971

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The only chance that 306k tranny has never been rebuilt is if god himself built it. Hopefully the front seal isnt walking out like the old 700R4 was notorious for doing. A worn tranny pump or its bushing can cause the torque converter to get canted and ruin the front seals ability to seal. I would be planning on yanking that tranny out very soon before it dumps all its fluid on the road. Economically the smartest thing to do then is get it rebuilt.
 

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