"Disappearing Transmsiion Fluid" - Drain & Fills

[SumpChump]

A friend of mine over on ToyotaNation has a 7th Gen Camry ('12-'14) with the U760E transmission 6 speed auto. We Camry guys recognize some of the delicate nature of a very busy 6 speed transmission as well as the rapidly firing selenoids in and out of torque converter lockup. Thus many are doing drain and fills.

The drain and fill have to be done very accurately to maintain a correct fluid level. The actual Toyota fill level procedure is complex. Here's the issue... despite painstaking measuring, accounting for cling on funnels etc.....The first time he drained (factory fill) 2190 ml @ 68F, the second- less than 2080 ml @ 65F and the time 1925 ml @ 60F. He's getting less each time. ALL parameters such as garage floor tire inflation are all kept constant. some are saying the new fluid is clinging more internally... not sure if I believe that. Others say that despite his accounting for funnel and container cling... that he is under filling slightly each successive time.


Your thoughts?

 

[JTK]

I hear you it's less, but ~100mL per measurement? That's two medicine droppers worth of ATF.

 

[KrisZ]

How was the new fluid added? Was it added using the fill tool and Toyota's procedure, or was it just the same amount that was drained?
I'm not that familiar with Toyota, but I know that in VW's case, the measuring tool at specific ATF temp is inaccurate and in most cases under fills the transmission.

Opinions vary widely on the subject, but IMO, I would rather trust the factory fill, since they use up thousands of gallons of ATF, the overfilling would cost quite a substantial amount and nobody running a business would throw away money like that. So their equipment is calibrated and highly accurate to avoid waste.
Therefore, if available, I would use the amount of factory fill drained and refill with the exacts same amount.

 

[Nate1979]

Is it possible that how the car was driven or cycled thru the gears leaves a little bit different fluid level in the pan each time? Could it be a coincidence that it is getting less and less and instead more fluid is being held in the lines, torque converter, cooler, etc?

 

[Cadenza]

This is a common concern on the Toyota Tacoma forums among those of us with the Asin 750E. I tried following the all the steps to achieve a perfect drain/fill Toyota would have you believe are necessary, but it really is no more difficult than
draining while at 115 -130 degrees (I use a scan gauge), measuring closely, and filling the same amount. So far so good on a '13 Tacpma and a '15 4Runner.

 

[SumpChump]

Originally Posted By: Nate1979
Is it possible that how the car was driven or cycled thru the gears leaves a little bit different fluid level in the pan each time? Could it be a coincidence that it is getting less and less and instead more fluid is being held in the lines, torque converter, cooler, etc?


That's what I was thinking.

 

[SumpChump]

Originally Posted By: KrisZ
How was the new fluid added?


Added via measured amount through a fill port on side of transmission. Not using temp method level check. Just an "exact drain and refill".

 

[Eddie]

What was Toyota thinking when they made a system that required an engineer with Temp/volume experience to change their ATF? Bunch of nuts probably cover it. )

 

[KrisZ]

Originally Posted By: SumpChump
Originally Posted By: KrisZ
How was the new fluid added?


Added via measured amount through a fill port on side of transmission. Not using temp method level check. Just an "exact drain and refill".


I would not worry about it then. But if the trend continues, that is less and less ATF is drained, I would perform the temp level check. Actually, I would add extra fluid to match the very first drain amount and then perform the temp. level check.