Author Topic: Automatic transmission shifting  (Read 3508 times)

lexon

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Automatic transmission shifting
« on: August 22, 2016, 09:12:59 »
Hello everybody!
Owners of 280 SL automatic, could you answer please, what is you RPM on 110 km/h for ex.? I have ~ 4500 RPM...too much.
I have automatic trans. and the switching (on position "4") is always 2-3-4, as I understand.
The 1st gear can only be used on position "2"?
I dont understand if my gearbox is working properly...

 

WRe

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Re: Automatic transmission shifting
« Reply #1 on: August 22, 2016, 10:58:22 »
Hi,
here you can find all necessary Information: http://www.sl113.org/forums/index.php?topic=23778.msg170168#msg170168; See attachments.
...WRe

ja17

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Re: Automatic transmission shifting
« Reply #2 on: August 22, 2016, 14:05:38 »
With position "4", first gear should also engage from a stop if the "kickdown switch" is activated when the accelerator pedal is fully depressed.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

TheEngineer

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  • '69 280SL,Signal Red,
Re: Automatic transmission shifting
« Reply #3 on: August 22, 2016, 15:05:24 »
The workshop manual page 03/15 reads: with rear axle ratio 3.69:
Motordrehzahl bei 100Km/h im 4. Gang 3140 bis 3315 U/min
And for you Yanks who are withering in the Colonies:
Engine RPM at 100 kilometers per hour in fourth gear
Please note that your rear axle ratio affects this number and if you have not woken up yet and still think that 4.08 is as it should be then your RPM are much higher. Go see your friendly mathematician for an explanation
'69 280SL,Signal Red, 09 cam, License BB-59U
'67 230SL, 113042-10-017463 (sld)
'50 Jaguar Roadster XK120, #670.318 (sld)
tired engineer, West-Seattle,WA

lexon

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Re: Automatic transmission shifting
« Reply #4 on: August 22, 2016, 19:25:39 »
Thanks for your answers!
I drived my Pagoda about 1200 km in Germany and each time I had a feeling thar one more gear is missing when I go more than 90-100 km/h.

Cees Klumper

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Re: Automatic transmission shifting
« Reply #5 on: August 22, 2016, 23:28:47 »
I swapped out my 4.08 axle for a 3.69 one many years ago. About a 10% difference and I've been quite pleased with that. But please note that these are very high revving engines so something to also get used to.
Cees Klumper
1969 Mercedes 280 SL automatic
1968 Ford Mustang 302 V8
1961 Alfa Romeo Giulietta Sprint Coupe 1600
1962 FIAT 1500S OSCA convertible
1972 Lancia Fulvia Coupe 1.3
1983 Porsche 944 2.5
1990 Ford Bronco II