ATF topping up

[dvd8n]

Hi

I've been having problems topping up my automatic transmission in my Legacy.
As far as I can tell I'm following the handbook.

I've topped it up so that when cold it's full (in fact slightly over -
oops).

But when hot, the ATF level goes DOWN, not up like the handbook / dipstick
suggest that it ought to. I can see that the fluid will expand when hot
(and the level go up), but surely also the fluid is spread throughout the
interior and workings of the gearbox through the running process and this
will cause an opposing reduction in volume? But the manual must be right!
It must be something I'm doing! But what?

Maybe my procedure is wrong:

I go for a short drive (maybe 5 - 10 miles).
I park up on level ground.
I leave the engine running.
I run the gear selector through all the gears, ending in PARK.
I get out the car, lift the bonnet & remove & clean the dipstick.
I use the dipstick to dip the gearbox.
The level has always gone down!

Any help appreciated.

David.

 

[Edward Hayes]

Wrong to top up cold as the valves and accumulators have drained down. When
you start it the parts fill and the sump level goes down. Fill when warm'hot
and engine running. eddie

 

[dvd8n]

I understand that the transmission should be done hot but I'm worried that
the cold dipstick levels are saying that it's over-filled already. Is it ok
to just ignore that?

D

 

[Edward Hayes]

Cold fluid levels are of little or no consequence since the true level is
the hot-engine running level. Ignore the cold fluid level. eddie

 

[dvd8n]

Thanks