i just repaired my vrv yesterday. my trans would not shift . i have a 1986 F350 6.9 mated to a c6 auto trans

now my trans shifts smoothy from low to 2nd at 32 kilometers an hour and from 2nd to drive at 42 kilometrrs.

if anyone wants to know what i did this may be a problem with a lot of these vrvs because its made of plastic .

 

Don't tease man. Let it out!

 

this is what it looks like inside the vrv with the round cover off. the yellow rod is flipped over in this pic. there is a small tooth at thr bottom of the yellow rod. it has been glued back on in this pic. i found the tooth in the small slot . if anyone is having trouble adjusting the vrv and modulator this could be the problem.
when re installing the yellow rod u need to rotate the green cam. the cam has spring preasure against it. alighn it with the tooth on the yellow rod and hold it in that position . then re install the cover with the 3 screws. you should be able to now rotate the cam anout a 1/2 inch and it should spring back.
P/S be very gentle. its plastic. can break easy. be sure not to rotate cam to much.
this is the vrv re installed but not adjusted. to get the proper adjustment you take the hoses off. use a hand pump and pump to 20 hg on the top port. put a vacuum gauge on the bottom port and adjust to 13 hg. you may still have to adjust the modulator down beside the trans . 1/8 th turn at a time till you get smooth shifts.
P/S this is done with engine not running. and throttle at idle position.
i had read some rather complicated instructions somewhere about calibrateing the vrv by disconecting the throttle linksge and return spring and the putting the throttle at WOT position and holding it there with the return spring. then to calibrate it they said the throttle needed to be rotated from WOT to idle 5 times. and the adjustment to be set at 7 hg. i did not do that. i could not see how that would do anything to calibrate it.