<VV> PG QUESTION

[Brent Covey]

Hi Mike,
> The PG was shifting hard , so I installed a new vacuum modulator( the 
> other one was leaking fluid into the vacuum line). Now I have too soft a 
> shift. It goes into forward or reverse gear OK, but the 1-2 shift tends to 
> rev up about 500-600 RPM. Some seems to depend on the throttle (vacuum?) 
> position. The down shift is quite smooth.
>
>   The fluid level looks good, except the dip stick is now kerput. Some 
> advice please.  Thoughts on what is wrong?

The modulators control the apply pressures for the band and clutches in 
'Drive' range- the greater the manifold vacuum signal, the softer and slower 
they shift. When you change the modulator, theres sometimes a slight 
variance between the two for thier 'tuning'- your new one seems to drop the 
pressures more than the old one did during high vacuum operation (light 
throttle).

Some are adjustable, you may discover an allen key fits into the vacuum port 
and can turn an allen screw inside to fine tune the new modulator. I believe 
turning the screw CLOCKWISE should raise the pressure. Some units may not 
have this adjuster screw built in, so dont get too frustrated if you cant 
find it. Somewhere around 2 turns in is about as far as I'd experiement with 
it. If the modulator is 'non adjustable' you can dimple the outside of the 
case (very carefully using a precision BFH and a large socket etc.) on the 
surface the vacuum nipple is on inwards to compress the spring inside a 
trifle and get a little more modulated pressure.

There is also some possibility your low band is out of adjustment and this 
condition was masked by the old modulator, in which case you might want to 
confirm its correctly adjusted.

Hope thats some help,
Brent Covey