then I guess that would be more the reason why you want to check level on cold because you don't want the transmission to starve on cold ? I know you don't want to run into foaming with overfilling too.
ATF level confusing - what do you make of this ?
- Thread starter youdontwannaknow
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Again, warm it up by taking a drive. Park it on a LEVEL surface. Let the fluid drain into the pan for 5 minutes. Check it.
*Easy Button*
BTW if it's on a slightly crooked surface the level WILL be off.
*Easy Button*
BTW if it's on a slightly crooked surface the level WILL be off.
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I use a laser pointer on a transit level to determine if the vehicle is properly positioned before checking. I then erect a fully equipped portable weather station to check wind velocity, ambient temp, and barometric pressure. Pyrometers, submersible probes, and infrared instruments are used to assure that the fluid is in the proper range for the reading I'm checking ..either hot or cold.
It's the only way to be sure.
It's the only way to be sure.
Originally Posted By: Gary Allan
I use a laser pointer on a transit level to determine if the vehicle is properly positioned before checking. I then erect a fully equipped portable weather station to check wind velocity, ambient temp, and barometric pressure. Pyrometers, submersible probes, and infrared instruments are used to assure that the fluid is in the proper range for the reading I'm checking ..either hot or cold.
It's the only way to be sure.
I take mine to NASA Lewis Research Center and have them level it on the laser moon rover simulator platform and then have one of the PhD Physicists check it for me....
I use a laser pointer on a transit level to determine if the vehicle is properly positioned before checking. I then erect a fully equipped portable weather station to check wind velocity, ambient temp, and barometric pressure. Pyrometers, submersible probes, and infrared instruments are used to assure that the fluid is in the proper range for the reading I'm checking ..either hot or cold.
It's the only way to be sure.
I take mine to NASA Lewis Research Center and have them level it on the laser moon rover simulator platform and then have one of the PhD Physicists check it for me....
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I don't believe the fluid expansion causes the higher hot than cold reading.
lets take the pan. it's about 8" by 10" (for argument sake).
now the difference between the cold and hot bit on the dipstick is about 1".
so, assuming the pan dimensions stay the same for the 1" rise this means that 80 extra cubic inches have been added to the total fluid volume.
that is 1.3 liters
on my camry the total capacity is some 9 liters - this means the heat expansion of the fluid is 14%!!!
i simply don't believe that any fluid can expand that much from 20 deg C to 80 deg C.
that is a temperature expansion coefficient of 0.00233 per degree C, which is huge! steel's co-efficient is 0.000012 per degree C, less by a factor of 195! Even if I made some gross assumptions it still does not explain a factor of 195 times more temperature expansion compared to steel.
therefore I can only conclude that there is a mechnical effect at work here in the way the fluid circulates. The fluid simply cannot expand that much.
lets take the pan. it's about 8" by 10" (for argument sake).
now the difference between the cold and hot bit on the dipstick is about 1".
so, assuming the pan dimensions stay the same for the 1" rise this means that 80 extra cubic inches have been added to the total fluid volume.
that is 1.3 liters
on my camry the total capacity is some 9 liters - this means the heat expansion of the fluid is 14%!!!
i simply don't believe that any fluid can expand that much from 20 deg C to 80 deg C.
that is a temperature expansion coefficient of 0.00233 per degree C, which is huge! steel's co-efficient is 0.000012 per degree C, less by a factor of 195! Even if I made some gross assumptions it still does not explain a factor of 195 times more temperature expansion compared to steel.
therefore I can only conclude that there is a mechnical effect at work here in the way the fluid circulates. The fluid simply cannot expand that much.
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