I have read some things about the ZF 6spd reliability and its ability to take increased power, so after installing a twin screw I started to look at what options might be available to beef it up.

After some digging it turns out that the Ford 6R80 is a close relative of the 6HP26/28 and that many of the upgraded friction kits and other components will drop right in. This makes me worry a lot less about the ZF box as the Mustang crowd abuses them with upwards of 1000HP and they seem to do ok.

Not knowing a great deal about the inner workings of an automatic transmission, I found this 40min transmission tutorial to be pretty interesting.

It may have even diagnosed a minor problem for me. My car clunks when shifting from reverse to drive and I know that it is coming from the rear of the transmission. I now suspect that the cause may be a failed anti clunk spring.


YouTube link:

 

Interesting video, helps me understand how that functions. Thanks

 

As you may have already found out, your ZF doesn't use the anti-clunk spring, in fact there is no OWC or mechanical diode as described in the video.
The most likely cause of your noise is some play in the output shaft splines, you can remove the flange and apply a small amount of Loctite to the splines before refitting.
Sorry the reply is so late but I have just stumbled across your video!
Cheers,
Dave