Our '66 chev 250 six banger with powerglide seems to shift too soon. I believe it has a 4:11 rearend in it and the amount of throttle seems to have no affect on when it shifts. TV linkage adjustments seem to make no change, could it be the vacuum modulator? Thanks
It certainly could be the Modulator, fist be sure it is getting manifold vaccum. Also since the truck has maybe been change at the Diff, some of those modulators have a tiny screw adjustment in the hole where the vaccum is, Hopes this helps Chb46
Finally got around to pulling off the modulator. There is vacuum to it but when I got it off, I found the vacuum side full of tranny fluid. Don't think that is a good sign! Will try to fish out the valve in there today and check it also. Bruce
yes if there is fluid in the hose the modulator is bad it is easy to change Rick Bradley tech2@chevyduty.com 1.816.741.8029 ext. 500
Finally got the new modulator, it was a bit hard to find here but it sure made the difference in shifting! One other question though, does the TV linkage adjustment have any affect on the shift point? My manual is unclear on the adjustment of it. Thanks! Bruce