the transmission could be going out or slipping or your Transmission Fluid could be low
Vacuum on an automatic transmission normally controls shift timing and would not effect downshifting (normally). Shifting is normally caused by internal fluid pressure in the valve body, with WOT control to over-ride shift points. Check the shift cable and make sure it is properly adjusted, if that is not it then the problem is internal to the valve body of the transmission.
if it is using trnasmission fluid you could have a bad tansmission modulator. take it to a shop
Assuming you mean the modulator on an automatic transmission... The modulator help to control the timing of the changing of gears in the tansmission. The modulator uses manifold vacuum to finetune the shift point, lower vacuum means higher load, throttle is open wider, shift point will be delayed.
manual stick shift BMW what cause to shke when i change in to the first gear
Same time you normally do, just drive slower. Make sure in each gear you don't over rev it because that will cause your tires to spin.
It is an AODE
A change in price level would cause movement along the demand curve, but would not cause the curve itself to shift.
The gears in your transmission may be sticking or worn out. This would cause your transmission to not be able to shift.
Normally the night shift should be paid extra but it depends on the company and the country where u live in.
what kind of pathogens normally cause mosaic and mottling
tansmission slipping
Inside the transmission.