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  #1  
Old 10-16-2015, 06:28 PM
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1981 300D w123 shift points

Hi, Im looking at a 300D (non Turbo) and It shifts at 21-22 mph (1-2) and at 41-42 mph (2-3) is this normal? Also, Could you change how soon it shifts to cruise in 2nd at 30mph?
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Old 10-16-2015, 06:44 PM
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Actually the car doesn't start off in first gear.....First is only obtained by stomping the peddle down before take off......There is a kick down switch behind the accelerator....if it is working correctly....This should allow you to be able to kick the trans down a gear with out have to manually do it via the shifter.....

As for the points, if you look at the speedo, the shift points are on the gauge....


First gear up to first dot
Second gear up to second dot
Third gear up to third dot

These are very high revving motors....At times it will sound like you are about ready to take off....

Also approaching 4 decades, these transmissions usually need to see a lot of maintenance....shifter bushings, neutral safety switch, vacuum components, fluid filter change etc to see the auto work like it should...

I believe this model also has the vacuum only controlled transmission, which means if you have a vacuum leak...the trans won't shift right....
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Old 10-16-2015, 06:48 PM
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Thanks, do these shift points sound right? the car is in almost perfect mechanical condition
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Old 10-16-2015, 07:24 PM
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Those shift points sound about right if your almost flooring it...It is [I]not/I] normal to be cruising around at 40MPH in 3rd, if that's what you're asking.

I am not sure if the '81 is all vacuum controlled, or if it has a bowden cable to adjust shift points. Could you pop the hood and look at the top of the valve cover to see if there's a cable?
The bowden cable is easily adjusted to allow for earlier shifts. If your transmission is vacuum controlled only, I'm sure someone else here can advise you on how to adjust those.
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Old 10-16-2015, 08:35 PM
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Quote:
Originally Posted by TheBoss930 View Post
Hi, Im looking at a 300D (non Turbo) and It shifts at 21-22 mph (1-2) and at 41-42 mph (2-3) is this normal? Also, Could you change how soon it shifts to cruise in 2nd at 30mph?
With 2nd gear start and two observed shifts it sounds like you're going into 4th a little over 40 and 3rd a little over 20. With your 3.46 rear end that sounds about right for just putting around town. With it floored it should shift close to the dots as JJ said. Want to keep it from hitting 4th? Put it in S.
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99 Mazda Miata 183,xxx miles.
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Old 10-16-2015, 08:56 PM
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Originally Posted by Skippy View Post
Want to keep it from hitting 4th? Put it in S.
Oh gawd, careful of that....or you'll have ever big asss new diesel truck.....thinking your attempting to race them or compete....ask how I know this

It is a good idea to do this though, as it helps to knock off/burn off the carbon deposits on the valves....

These cars love to be driven hard.....though few do it....
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Old 10-16-2015, 08:58 PM
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I used to have a 1973 220D that started off in second with a drop down full throttle switch, but my 1980 300D has always started off in first gear since it was new.

Richard
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Old 10-17-2015, 07:52 AM
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Quote:
Originally Posted by TheBoss930 View Post
Hi, Im looking at a 300D (non Turbo) and It shifts at 21-22 mph (1-2) and at 41-42 mph (2-3) is this normal? Also, Could you change how soon it shifts to cruise in 2nd at 30mph?
The '81 300 D have 722.118 transmission with vacuum control. It starts in 1st gear.
For shift points see att. file, second column.
Attached Files
File Type: pdf 123.130.pdf (22.9 KB, 333 views)
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Old 10-17-2015, 09:02 AM
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Quote:
Originally Posted by cooljjay View Post
...

As for the points, if you look at the speedo, the shift points are on the gauge....


First gear up to first dot
Second gear up to second dot
Third gear up to third dot

...
You should know better by now good sir!

Those dots on the speedo are the maximum allowed speed in each gear. These are "warning dots" if you like.

See this from the owner's handbook (first paragraph) =>





Quote:
Originally Posted by TheBoss930 View Post
Thanks, do these shift points sound right? the car is in almost perfect mechanical condition
Depends on the accelerator position - see below

Quote:
Originally Posted by Ceristimo View Post
Those shift points sound about right if your almost flooring it...
Indeed - see below

Quote:
Originally Posted by rasper View Post
I used to have a 1973 220D that started off in second with a drop down full throttle switch, but my 1980 300D has always started off in first gear since it was new.

Richard
Quote:
Originally Posted by Dr. Sternschnuppe View Post
The '81 300 D have 722.118 transmission with vacuum control. It starts in 1st gear.
For shift points see att. file, second column.
I'm glad it is clear that the vacuum only 722.118 starts in first - mine does too!


In the PDF posted by Dr. Sternschnuppe

There are three types of accelerator position

The first one "leergas" means a little bit of "throttle" (<= bad term for most diesels I know, but sounds better than a little bit of "accelerator" in English!) So this is a bit above idle : almost idle.

The second one "Vollgas" is full "throttle" with out the kick down being engaged

The third one "Ubergas" is the best and most superior type of gas of them all! Pedal to the metal - kick down engaged (brakes are for pussies - die muther ****er die)
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Old 10-17-2015, 03:01 PM
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Originally Posted by Stretch View Post
You should know better by now good sir!
Appoligizes...Forgot to add that "Max Allowed"

Then I also can keep up on who's trans starts in first and who's doesn't...All these us spec luxury gadgets confuse me after awhile....
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Old 10-17-2015, 04:22 PM
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Quote:
Originally Posted by cooljjay View Post
...
Then I also can keep up on who's trans starts in first and who's doesn't...All these us spec luxury gadgets confuse me after awhile....
Tell me about it - I have no idea what the secret for that "starts in second" thing is.

I'm kind of hoping the Dr. can say!
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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!
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  #12  
Old 10-17-2015, 06:25 PM
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Originally Posted by Stretch View Post
Tell me about it - I have no idea what the secret for that "starts in second" thing is.

I'm kind of hoping the Dr. can say!
Oh I know! I know there has been so many "debates" over it....over the years.....I know my personal haunted, one off 78 starts in 2nd unless I kick it down....but I've stopped trying to relay that
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  #13  
Old 10-17-2015, 09:04 AM
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Oh yeah shift point data for other transmissions of the same era is posted here =>

DIY W123 Transmission Diagnose and Adjustment 722.xx OM 616-7 - Mercedes-Benz Forum
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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!
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  #14  
Old 10-17-2015, 10:59 PM
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Mine starts in whatever gear I want it to.
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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 401,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 26,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.
99 Mazda Miata 183,xxx miles.
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  #15  
Old 10-19-2015, 03:46 AM
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Originally Posted by Skippy View Post
Mine starts in whatever gear I want it to.
Yeah but only when your left foot is firmly down on the clutch pedal (or you happen to be flying down a steep hill at speed)!
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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!
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