I have an 89 560sel with 209k miles that is new to me and I do not any history on the car.
I had it in to an independent shop to service the tranny and while it was there to look at the throttle linkage. They drained the fluid and torqu.conveter and replaced the filter. Also replaced the modulater valve??( What controls the vacum to the shift points on the tranny)
Well the hard shift got a bit harder. Shop seems to think it may be the clutch packs from 3rd to 4th. The up shifting is good, a bit firm but good.. The down shift from 4th to 3rd at 60mph is hard!
Couple ?’s #1 could this still be lack of vacuum to the tranny or an adj.to the modulator valve??
#2 If it is the clutch pack. Would it still shift hard when Manually down shifting with the shift lever vers. Stepping on the gas peddle to pass?? When I down shift Manually it is smooth as silk but when accelerating to pass it hits HARD.. Any thoughts or advice would be appreceated Thanks Tom Alpharetta GA

tjseitz2001,
Since the modulator regulates the amount of vacuum and resulting smoothness or harshness of shifting and you said that was just replaced, I would first check the line from the manifold to the modulator to ensure no leaks. If none are found, then I would attempt gradual adjustments at the modulator until shifts are as smooth as you like. This, to me, does not sound like clutch packs.

Bob

Bob, thanks for your thoughts. you adj. that at the modulator??correct?
Dont know if this is related or not but thought I would mention it. I have an issue with no heat comming out of the floor vents(most of the time) vacuum related, with the pods (just guessing here from what I have heard and read) If this is true could this affect the vacuum to the shift modulator? Thanks again. Tom

Tom,
The modulator adjustment is on the modulator itself on the side of the transmission. If you've never done this before, don't. Ask your tech to check for leaks in the vacuum line as I mentioned and let him adjust the modulator.

The vacuum line feeding the transmission is exclusive from the vacuum system for the HVAC system/pods

Bob