Cold Start issue Automatic Transmission

kys911t

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I have a 74 3.0cs Automatic Transmission. On cold starts in the morning or it has been sitting for a while, the transmission does not immediately shift from first to second. Once the car has warmed up and after the first shift I have no problems. Drives fines and shifts fine. Any idea what is causing this. Or is it time to do a rebuild?
 

bluecoupe30!

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Can you provide a bit more history? When these automatics sit for a while, the transmission fluid drains into the bottom and will become so heavy it will pass through the pan gasket and leak out. Obviously, if below a minimum level of fluid, transmission will behave differently. Once warmed up, there is fluid in circulation and gearbox may perform normally. Can you comment on fluid level and if you have noticed a puddle under your car? Another example of why these cars just should be driven regularly. ;) As Chris has stated, never a bad idea to clean filter and replace gasket on these half century old cars. Let us know how it goes.
 

kys911t

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The car does not sit for any period of time as it is pretty much my driver. The I checked the level and although a little hard to tell looks like its normal. I did notice this started coincidently when we had the radiator repaired and not sure this had anything to do with it. I will do as suggested and have the fluid drained and screen cleaned and see if this happens. Thanks everyone.
 

bluecoupe30!

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Automatics have the transmission fluid run through the right side of the radiator. When the rad is out for any reason, you lose a certain volume of transmission fluid. But if you checked the level after the service, I am out of guesses :cool: Good luck and let us know how it performs after filter rinse and new fluid.
 

kys911t

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It looks like the level is fine with it running. Going into the shop next week to have it checked.
 

Arde

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The car does not sit for any period of time as it is pretty much my driver. The I checked the level and although a little hard to tell looks like its normal. I did notice this started coincidently when we had the radiator repaired and not sure this had anything to do with it. I will do as suggested and have the fluid drained and screen cleaned and see if this happens. Thanks everyone.
People think the transmission fluid goes through the radiator just to cool it. It also goes through it to warm up the fluid faster. Is it possible the radiator service perturbed either the flow or the heat exchange aspects of the transmission fluid through it?
 

bluecoupe30!

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People think the transmission fluid goes through the radiator just to cool it. It also goes through it to warm up the fluid faster. Is it possible the radiator service perturbed either the flow or the heat exchange aspects of the transmission fluid through it?
Hmmm, You could be bang-on with this. It is my observation that pretty much everything and everyone is "perturbed" these days. In fact, I have retired my perturbOmeter to the shelf, as every reading is maxed out. So looking forward to the mechanic's opinion about this symptom. ;)
 
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