Automatic Transmission clutch losses?

[icrman]

Has anyone ever measured parasitic losses from the clutch packs of various Manufactures of Automatic Transmissions?
What I mean is say, with the transmission in top gear, the unapplied clutches will be coasting and washed in Transmission fluid, so there is a certain amount of drag or loss from this. Also I realize it will be different from transmission design and clucth pack size and design. I'm just looking for some close approximations.
Thank you.

 

[tbuelna]

icrman,

From SAE Paper 1999-01-1259, clutch pack drag parasitic losses in a typical AT represent about 75% of losses in the transmission. The total losses in an AT can be from 10% to 20% depending on the operating conditions.

Worst case, 75% of 20% would be 15%. Close enough for you?

Regards,
Terry

 

[crysta1c1ear]

http://www.eng-tips.com/viewthread.cfm?qid=81815

 

[icrman]

How about band type clutches. Is there any info on them?