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1995 SL600, 1983 380SL, 1987 560SEL, 1974 Lotus Europa TwinCam Special
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Discussion Starter #1
I've searched this site and a general google search for specs on what has to be done in the valve body for a first gear start. I have a 600SL that had the first gear start installed when I bought it. Didn't know it was there - assumed it normally started in first. I had a problem with the valve body ended up getting a replacement. Now it starts in 2nd. OK, no biggie. Now tranny blows up and I';m getting a rebuilt but I'd like to get the valve body changed to first gear start like before. I found a general description of the changes and details of moving spring from in front of to in back of something (I have the site printed out). This forum has posts that there needs to be a ball change as well. Anybody know exactly what that is?

Thanks

Joe
 

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1992 SL300-24, 1998 BMW 750iL
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SL55, 300SE, GL450, Daytona 955i
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This never stops to amaze me... why would anyone want to make a car jerky?

at low RPM, the first gear makes the car move like a tank, with neck snapping jerk...

the only practical use for the first gear is to accelerate at WOT (wide open throttle), so you will get the best 0-60, and not have to worry about the shift jerk...

Guess what though, Mercedes agrees, and that's exactly what your car does from factory...
 

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2012 E350 - 1994 SL600
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This never stops to amaze me... why would anyone want to make a car jerky?

at low RPM, the first gear makes the car move like a tank, with neck snapping jerk...

the only practical use for the first gear is to accelerate at WOT (wide open throttle), so you will get the best 0-60, and not have to worry about the shift jerk...

Guess what though, Mercedes agrees, and that's exactly what your car does from factory...
I installed the FGSS and my transmission shifts smoothly when started in first. I haven't found my car does any of those things you talk about. Have you actually experienced this? I also installed a switch which allows second gear start if I want that.
Doug
 

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1995 SL600, 1983 380SL, 1987 560SEL, 1974 Lotus Europa TwinCam Special
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Discussion Starter #5
Guys, I'm not interested in FGSS. My car already has the mechanical version on it except for the valve body which was replaced by a factory valve body without the required changes and I just want to put it back where it was. I don't think there is any problem with having a mismatched first gear but the tranny blew up and before I put in a new one I'd like to make sure it doesn't happen again.
 

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91 500SL, 93 600SL, 95 S600 coupe, 97 S320, 99 ML430, 2003 CL600, 94 SL600, 97 Kawasaki 1100 STX
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Had 92 500SEL. Replaced tranny on it with one that came from 92 400E and it always started in 1st gear :) I had to adjust kickdown cable along with pressure on shift modulator on driver side of the tranny and shifts were pretty smooth.
On my current 91 500SL 1st to 2nd shift on low RPMs are kind of jerky, hate it. My guess is that valve bodies that have first gear start are modified to lessen 1st to 2nd jerk. And I too would be interested in valve body modification for 1st gear start, not FGSS module but mechanical mod. Too bad I sold my 92 500SEL with that 1st gear valve body and never took any part numbers off it :(
 

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1997 SL600 Brilliant Silver Sport with grey/dark metal interior, 234K miles
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For a V12, in heavy stop-and-go traffic; the combination of low 1st gear, 400 ft/lbs of torque and drive-by-wire makes for a less than smooth automotive experience.

I only toggle the W/S switch in heavy stop-and-go traffic.

Your original valvebody already had 1st gear capability, accessing it on demand comes by way of an electronic switch.
 

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I installed the FGSS and my transmission shifts smoothly when started in first. I haven't found my car does any of those things you talk about. Have you actually experienced this? I also installed a switch which allows second gear start if I want that.
Doug
Mercedes starts in second by design to provide a smooth ride, of course its more of a taste thing to rule what is jerky/noisy and what's not...

The first gear can be accessed in one of 2 forms:

- kick down switch at take off (full throttle).

-shift manually to B at take off (partial or full throttle), then upshift as you go.

there is absolutely no practical use for first gear in normal driving with normal acceleration under partial throttle that I am aware of...

can any pro-1st gear guys enlighten me what do you gain from 1st gear start in D at partial throttle?

am I missing something?
 

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97SL500R129, 01ML320W163, 94E320W124 & 93500EW124
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... any pro-1st gear guys enlighten me what do you gain from 1st gear start in D at partial throttle?

I'm not a pro-1st gear guy. But, I have some experience on the subject. My 500E is equipped with first-gear start valve body so it always starts on 1st gear. If I don't pay attention, I'll spin the wheel on take off which isn't good in slippery condition. Also, during take off, the RPM is high with low speed and this condition (I observed) resulted in poor gas mileage. I minimized the shift "jerkyness" from 1st to 2nd gear by adjusting the vacuum modulator. I agree, that take off is not as smooth as 2nd gear start. The gain on 1st gear start? Quick take offs and longer skid marks:D

On my SL I can toggle w/s to choose 1st or 2nd gear start and I believe the 722.6 transmission normally starts on 2nd gear. So, I was wondering why would the OP want to install 1st gear start valve body?
 

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The gain on 1st gear start? Quick take offs and longer skid marks:D
Understood, but you see, you can do just that by shifting to "2" or "B" and using the kick down switch from factory, without modifying the VB and make the car forever harsh, or spend 300 dollars on a module that presses the kickdown for you, before your pedal reaches it...

not to mention, high RPM at low speed = high, VERY HIGH torque... hence the wheels breaking loose...

torque, as we know, breaks things, things like engine mounts, friction plates in the tranny, flex disks in the drive shaft, differential gears, rear suspension rubber bushings, tires... amoung others...

these components will wear and fail much faster if you beat them constantly with high torque for no reason...
 

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2015 Jaguar XF R Sport Twin Turbo, 1992 500sl Pano, 1999 CBR 1100XX, Super BlackBird, Jaguar X Type
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On my 92 500sl, if I want to make a quick getaway 1st gear start. The procedure is to move the stick from D to B and back to D while stationary. This tells the car you want a 1st gear start instead of 2nd. It will then start in first and move up as normal.
I only use this when waiting at traffic lights and some one is sat next to me blipping their throttle lol!
 

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So has anyone taken a 400E (non ASR) valve body and put it in a 500SL to get the 1st gear starts?
 

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91 500SL, 93 600SL, 95 S600 coupe, 97 S320, 99 ML430, 2003 CL600, 94 SL600, 97 Kawasaki 1100 STX
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So it's early non-ASR 400Es had first gear start valve bodies? I replaced transmission on my 92 500SEL for 92 400E transmission and now I remember that it was non-ASR 400E. It always started in first gear. Adjusted vacuum modulator and had to give little less gas at take offs so there is no jerk when shifting to second. Shift was almost undetected but if you press on gas it took off nice and fast. Personally, I liked first gear take off.
 

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So it's early non-ASR 400Es had first gear start valve bodies? I replaced transmission on my 92 500SEL for 92 400E transmission and now I remember that it was non-ASR 400E. It always started in first gear. Adjusted vacuum modulator and had to give little less gas at take offs so there is no jerk when shifting to second. Shift was almost undetected but if you press on gas it took off nice and fast. Personally, I liked first gear take off.
Did the 500SEL originally have ASR, or no?
From my understanding this shouldn't work (if it did have ASR) when swapping with a tranny from a non ASR car.

Or is it the differential I am thinking of? :confused:
 
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