Trans fluid level - totally confused

[420 SE]

G'day

I'm now totally bewildered by my trans fluid level.

My trans seems to 'flare' b'ween 2 - 3 and 3 - 4 when it has warmed up. Not always, but often. The trans was rebuilt 1 year ago.

I've read you should check the trans fluid level with the trans warmed up and in drive.

My owners manual says when cold the fluid should be 10mm below the dipstick miniumum level, and when warm never above the upper level - but it says check it in Park.

When I check it in Drive - the is no fluid on the dipstick, when I check it in Park it's at the halfway mark when warm, when cold it's above the full mark!! I would have thought it went up when hot, not down.

Should I be adding any fluid??

I'm really confused because it was overfilled and I had to syphon some fluid off.

Add or subtract???

[t walgamuth]

checking it in drive. seems risky.

in park, idling i have always thought.

tom w

[420 SE]

Thanks Tom, I do check it in Park. When I did it in Drive I had my wife put it in D with the brakes on.

I'm still confused about the level going down when warm/hot. This seems completely wrong.

[t walgamuth]

yes, i would expect it to go up when hot too. but if checking when cold is it running?

tom w

[420 SE]

Yes

[Hatterasguy]

Check the trans fluid level when the car is on level ground. The trans should be in park, with the engine running, and fluid should be warm.

[420 SE]

Thanks Hat, thats how I do it.

I still don't understand why it is going up when cold and down when warm/hot?

[beylerbeyi]

I am not an expert but before the check you should go thru all level 123-D-R etc. then get to park and look for level. That way torque converter and system fully filled with the fluid.

[t walgamuth]

and the fluid level is correct when warm,

i would,

fuggitabouditt

tom w

[Palangi]

Warm doesn't get the fluid to full temperature. The fluid level will vary with temperature. Drive it for an hour, then let it idle for 5 minutes before measuring.

[Hatterasguy]

I don't know why, maybe as the fluid warms up it gets thinner and the pump moves more of it? Just a wild guess though. I have always checked it like I posted above and have never had a problem.

Unless their is a leak the level should never change.

[Palangi]

The trick is to measure it the same way every time. If you're gonna measure it hot, make sure it is at full temperature every time. If you're gonna measure it cold, do it stone cold in the morning every time.

[420 SE]

Thanks guys, I am now happy the level is right, at the full mark when the trans is in park, on level ground, having been driven for a while, with the engine temp at 80c, within 1 minute of having cycled through all the gears and with the car running.

I am ignoring the level being higher when cool/cold.

I am still having the flaring on occasion so now I am going to attack the trans modulator and try turning the little adjustment 'T' thingy and see if that helps.

Am I right in understanding I should turn it anticlockwise to get firmer shifts/less flaring?

Cheers

[Secret Squirrel]

Have you installed the K1 Spring kit to cure flaring problems?

Run, don't walk, to the dealer, get a K1 kit!!!

Do that before you start messing around with modulator settings.

These transmissions seem to be super-sensitive to fluid levels. Mine was shifting really quick 2-3 in the cold weather (had never gone through a winter with it yet) and started working fine once the weather got above 40F. Added a 1/2 quart of ATF because it was low when I checked during a hot/level/park and it made all the difference. Today it's 25F out and it's shifting just like it did when 84 the other day.

[420 SE]

Thanks Secret Squirrel

That's a new one on me but I'll look in to it.

The only caveat I put on it is the trans was rebuilt a year ago and the flaring only occurs (and not all the time) when the trans is warmed up/hot.

Do you think this makes any difference?

Cheers