Hi All,
I see a lot of shift kits listed as prevents (,NO YO YO) what exactly happens to a trans when it yo yo's ?
Only asking because at full throttle(pouring the coil to it) I have felt sort of an extra shift after it was already in 3rd gear is this that condition ?
Thanks for your answers. Jimi

The no yo yo kit that TransGo sells is a valve that replaces a valve in the valvebody.

It allows the converter to fill while in park to eliminate the no drive condition on initial startup.

Hm. I never knew that phenomenon had an actual name. Learn something every day.

Same here. I always just start mine in neutral to fill the circuit.

trans-go has a lot of No YoYo kits available for many makes and models.
there are different parts included, [springs, valves, shims, etc.] depending upon the transmission being worked on and the condition being addressed.
i have used many of these kits over the years, and i believe they are a good bang for the buck.
the instructions at times seem weird, as if the guy writing them has an odd sense of humor. [like mine ]
does the OP have a specific transmission issue that needs addressed ?

There is an auto trans phenomenon often referred to as yo-yoing; it's a bucking / jerking on the upshift. There are numerous causes, not sure if the Transgo kit is aimed at this or if they just used the term.

I was always told that a yo-yo is when a rebuilt transmission comes back with a problem. The no yo-yo kit would mean it fixes it so it doesn't come back to the shop.

Thanks Everyone ,
Just wanted to understand the term so I can identify it .
And have a Merry Christmas. Jimi

Also referred to as a "boomerang".