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Discussion Starter #1 (Edited)
hello

i have a 300d -88 which ive changed the automatic transmission since the old one was bad when i bought the car,
and i got a cheap automatic transmisson from another 300e,
now i got the problem that the car wont shift up when i use about 3/4 or more of trottle, it shifts up at first gear if you use the kickdown but then from 2th to 3rd and from 3rd to 4th.
it just max out the gear and engine running at max rpm but as fast as i let of some trottel it shifts fine in to the next gear.
hope you understand:p
the number from the transmission 124 270 10 01 722 320 02 81 35 67

also i have a question about a some sort of vacuum port that is on the control pressure wire.
what is it supposed to do?
the vacuum port is currently plugged:p

thanks for replys:)
 

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The 300E & 300D use similar but very different transmissions.

The 300E uses a 722.3 transmission, while the 300D uses a 722.4.

You need to find a good condition 722.4 transmission.
 

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Discussion Starter #3 (Edited)
thanks for the answer,

it really works fine if you either drive with less trottel or you lets say half trottel then it shifts just fine all gears and if you use full gas and then "manual" shift you hold gas to wanted rpm and then let of your foot and then it shifts up,

but you cant change the gear shifting somehow? i mean for example lower the speed it uses to put in the next gear?:)
also what is it that makes the transmission decide what gear to use?
vacuum?
or is it only the control pressure wire?
and the vacuum is only used for how smooth it engages the next gear?
 

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The control pressure determines when the shifts need to occur. Be sure to check and adjust the other end of that cable at the throttle body/intake as well. If it's too loose or too tight you will have erratic shifting.

The vacuum line is for the modulator. Without the vacuum line in place, the modulator is out of action and will result in harsh shifting, which will also hasten the new trans demise.

Check these links for proper modulator adjustment

PeachPartsWiki: Transmission Vacuum Modulator Adjustment

http://www.peachparts.com/Wikka/OM603TransVCV2
 

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Snurbo,
The vacuum modulator is at the left of the trans and the blanked off one you refer to at the right is for the economy/standard switch setting as found on some models.
You are not missing anything without this as it would just eliminate your first gear from the shift pattern, unless you hit kickdown.
Sounds like your cable is set too tight.
Try experimenting with the cable disconnected at the throttle end and you will get fast upshifts then take it from there. (put the cable back on slack and tighten till you get what you want).

Boyd:)
 
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