ZF oil level rises

[Mikems]

Last time I changed the auto trans oil & filter I checked the level the normal method. I then rechecked it about 1 minute latter, without going through the gears & the level had risen. I repeated this over a period of about 5 minutes & the oil level had risen about 100mm up the dip stick. I tried again the next day with the oil cold & the same thing happened. I don't recall this happening before. Has anyone got any thoughts on this?
Thanks.
Michael.:confused:

[Blknight.aus]

potential causes include

emptying of the cooler. if it was full when you checked it the first time and it had drained the second youd get the rise

not on the same level of ground

if youd shut the engine down the TC would have drained back into the sump same as for very slow speed operation. if you just leave it idling the TC will empty a little bit.

The dipstick might be picking up splash if the oil cooler is working when you check the level.

you might have had fluid trapped in the dipstick tube and are getting a false reading.

if you havent cycled all the gears then the oil in the clutch packs will drain back into the sump

the oil expands as its getting hotter so if its been left idling then its going to warm up.

Hows the fluid look so long as the fluid is not getting contaminated then you should be right.

[George130]

Yep dave is right.
Thats why you need to check it at idle in neutral after cycling through each gear possition.

[Mikems]

Thanks Gentlemen,
I understand, from what you have said, the correct level would be immediately after cycling through the gears & it is normal for the level to rise after this.
Thanks again
Michael.

[Blknight.aus]

dont forget to check it with the engine running.

what your doing when you check it is getting normal fluid levels set upthrough out the gearbox (TC, clutch packs+ galleries) and the oil that remains is your reserve of oil for cooling purposes,longevity of the oil and to ensure that hte pick up stays submerged all the time.

start it, cycle it through at least D,N,R,N (you can use park as well) leave it in nuetral with the engine running then check the oil level. I always dip twice to ensure Im getting a clean reading and NOT the remains of the oil level from when it was stationary.

If your going to do that check the oil level when its cold and the engine is stopped if whats happening is as I said when you check the oil level after cycling the gears and with the engine running you should find that its gone down but is now inside the normal oil level marks.

[harry]

Last time I changed the auto trans oil & filter I checked the level the normal method. I then rechecked it about 1 minute latter, without going through the gears & the level had risen. I repeated this over a period of about 5 minutes & the oil level had risen about 100mm up the dip stick. I tried again the next day with the oil cold & the same thing happened. I don't recall this happening before. Has anyone got any thoughts on this?
Thanks.
Michael.:confused:
auto fluid expands quite a lot when heated.
so it is a normal occurance