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Overfilled auto trans....have I screwed it ?

LatinDancer

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I have a VY series 2, and today I attempted to change the auto transmission fluid myself.
I undid the transmission hose at the bottom of the radiator, put the car in neutral, started the engine and trans oil got pumped out. I put more in, and flushed it out the same way.
All good.
Then the stupidity kicked in....I accidentally overfilled it....a LOT. So I started the car and briefly put it into gear a couple of times just to get the oil circulating. But when I went to dump all that oil by taking off the lower trans hose at the radiator again (with engine running and in neutral), nothing came out. Even in gear, nothing came out. Well, about a cupful or two.
Surely I have not blown some kind of seal ? Aren't oil pumps mechanical gears ?
Or has the computer gotten a wrong message because of the overfill and shut down the oil pump somehow ? Can it do that ? And if so, can I just disconnect the battery for a while and re-set the computer ?
 

mechanic

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The oil pump is driven by the engine. If the engine is running, the trans oil pump is turning.

how long did you run the engine for to drain the trans? did you run it dry with the engine still on?

I wouldn’t recommend this method of draining. You wouldn’t drain your engine oil that way, so why do your trans that way?

i have no idea what the problem is, but you probably need a trans guy to test the oil pressures. Hopefully the oil pump or other lubricated component isn’t damaged.
 

LatinDancer

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I ran it for about a minute....3 times.
I had been wondering about running it dry, but the engine and trans are only idling, so I thought it would be OK. It's not really dry for that short time....there is residual oil lubricating the components.

Anyhow, thanks for your answer....I will take it to a specialist.
 

mechanic

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Pretty sure the auto trans oil has a thermostat in it, just like the engine coolant - it may just be too cold to flow. Get it up to temp and then try draining it again.

... and don’t drive it too far with overfilled oil. If it churns, aerates and comes out the filler tube it may start a fire.
 

Immortality

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The pump in the trans is driven off the converter which is turned by the engine. The pump is of a rotor/vane design. The fluid going to the trans cooler comes directly from the converter and should flow when the engine is running. Never heard of a transmission thermostat (in the transmission that is).
 

Trevor loves holden.

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What's the point changing fluid and not change the filter? I think your problem is that your pump is dry , Best way is do two changers in a short time.
 
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Trevor loves holden.

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The trans fluid gets sucked up from the pan thru the filter to the pump then goes thru the body valve then depending on the feed and pressure at the time it feeds the clutch pack to engage that gear as well at the same time feeding the torque converter then leaving the torque converter out to your radiator then back to your pan.
 

Trevor loves holden.

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Now thinking about it if your filter is blocked or the seal is leaking on the filter stem then it can not suck up to your pump, also if there is no oil flow from the radiator hose is because no oil hasn't reached the torque converter, if your oil stick when cold isn't around the cold line then you haven't got enough oil in the pan, also if the wrong filter is used then oil wont pick up as the filter wont be submerged in fluid therefore starve the pump as low oil would do. Filters come in a deep pan or shallow pan.
 

VT2Commie

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There is NO thermostat in the 4l60e there is however a pressure regulator......
A stuck or damaged pressure regulator valve could cause,
High or low line pressure
Slipping clutches or bands or harsh apply
Transmission overheating
Low or no cooler/fluid flow
 
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