I recently had my first start up on a brand new 4l60e from performabuilt, did the initial break in/fill procedure.

But it intermittently will build up enough pressure to drip out of the top of the dipstick on to the valve cover.

It's not overfilled, before I started it today it was just under the hot mark (cold) engine off

Started it up and checked the level, and it's at about the warm mark.

I let it idle for 30 min to bring trans up to operating temp (roughly 150) according to my trans temp gauge that's in the pan.

It starts dripping on to the valve cover

I've been trying to get the proper fill on this for a few weeks, I bring it up to operating temp. Check fluid. Even drive around the block for a minute just to cycle gears.

Trans has approx 15 miles on it, I've driven it in 3 mile burst. Each time checking fluid and then adding if necessary.

Everyday has a new reading, only once has it been the same. I've even drained 4 qts out and started over in case I overfilled it.

Started the fill procedure over again twice.

The problem is it never comes out of the breather tube, always the top of the dipstick

Trans temp has never been over 185 during any of the testing

Seems to drive and shift fine, I can even feel lockup engage in 4th gear once I hit 40+ mph

Anyone have any tips? I'm kind of stumped.

 

Sounds like the Vent may have become blocked or bent closed somehow this may make a little mess but with dipstick removed maybe put a cup over it to limit spray around with engine cool try blowing some air through vent tube , It should push fluid up out of the dip stick if not it is blocked if it does it still may have been blocked and cleared with the air if so then clean up and try driving again. If air does not come through pushing fluid out then try to determine why the vent is blocked could be bent or mash closed or something could have gotten up in it.
If its not bent or mashed try pushing some stiff wire up through it to clear it.
Give us a call if you need anything>
Frank

 

Will the opposite work as well? Blow air into the dipstick and see if anything comes out the vent?

 

Well should if vents open yes but if the vent is blocked you risk pushing a seal out like front seal, linkage rear etc.

 

Ok I tried the compressed air, it seemed to have worked. The level has been stable all day, I'll check again tomorrow. Weird.

Can a clogged vent line cause damage? Other than the pressure venting through the dipstick tube?

 

Could have been something up in the vent I have seen strange things even a bug and no cannot cause damage other than venting.