Brian, I kinda interpreted his post as saying that he transferred the 1st-gear mechanism from the previous 420 car to the later 300SE? Dunno.
I had heard of that electrical "trick" a few years back, but I assumed it actually let the car begin to start in 2nd, then quickly bumped down into 1st.
I checked the service books to see if I could find a reference to a 300 W126 with a taller gear, didn't see one.

That harsh 1-2 shift is really only objectionable on the first shift or two of the day, so certainly not a show-stopper. Might could be virtually minimized by just a conditioned right foot when starting out stone-cold.
but, there are plenty of ways to modify shifting force pretty easily.
I had a slightly slow 2-3 and a slightly firm 3-4, so i used a K2 valve kit, and then tweaked the Bowden cable and the modulator to obtain the shift balance I wanted.

On a bright note: a good friend of my son is now a painter at a local MB dealer. We are getting the gray bumpers and side cladding repainted on 'Ol Pearl next week. The sun had faded/peeled the clearcoat a bit. She should look flawless again. The body paint is original artic white (with no clearcoat) and still looks new after 21 years of daily driving.

Press on,
DG

If so, then the FGS module that is commonly available for the V8's would work on the I6. However, their is a very strongly worded post by Satish Stummala that contradicts this. I need to give Satish a call and query this issue.

That trick simply engages the kickdown solenoid until the vehicle reaches about 7 mph............then it releases it. It works fine for the V8's.

I'd still prefer a modified valve body to do it hydraulically, if I can.

The 2.47 diff is currently in the trunk of the SD..............half way back to Blue Point!!! Also got the complete cluster so I can use the speedo from the 420 as well.

It appears that I'll have the diff installed well before the valve body gets modified, so I can do some first gear start experiments manually and check out the harshness of the 1-2.

Easy test: wire up another switch to the wires going to the kickdown switch, actuate it by hand, and see if you can move off in 1st gear...

-J

__________________
1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.

Yep...........but, if Satish has some inside dope...........I could save the time to rig the test.

Spoke with Satish via e-mail today:


So, that ends that approach.

While you've got all these guy's ears you should ask them if there's a way to force a 722.3 that normally starts in 1st to start in 2nd

-J

__________________
1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.

...........now why would you want to go and do that.........??


They did put four gears in the thing for a reason, you know...........

Hopefully I got a more useful question then above,
On the OT, You mind asking how to get the transmission to shift all gears at WOT at above 4500 RPMs. For a performance related project, the standard 1-2 shift is too short for my taste. The standard 3-4 shifts are great at around 4500. Tweaking the bowden cable doesn't do it for all gears.




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__________________
1983 123.133 California
- GreaseCar Veg System

You only get to push that diesel over 4500 rpm..........ONCE. After that, it's spare parts.

You do realize that the maximum hp for the thing is at 4400..........???

I get scared when I push the 617 up to 4000..............

Yes I realize that. But there will be modifications to the motor and if the motor breaks, then it's on me. Nobody else.

In any event 1-2 and 2-3 shifts still doesn't reach 4400. I would love for it to do so.


.

__________________
1983 123.133 California
- GreaseCar Veg System

You can do it manually for the infrequent use of the engine at that speed............

Or you're going to have to start replacing the tired springs in the valve body if the Bowden cable doesn't provide sufficient adjustment. There are no other options as far as I am aware.

Well I know the valve body would have to be modified, just question is what parts, i.e. spring rates, check balls etc, are needed to accomplish this requirement.

I have the superior shift kit installed on the K1 and K2. B1 of the kit softens the shifts, which is not what I am looking for. The TV pressure control valve spring in the kit eliminates the stacked shifts at all points. Which is not a problem here.. Or is it? But I don't think it's a stacked shift, because all the 722.3 do it. Oh by the way, my 2-3 shifts at 4400 at WOT, so I'm really focusing on 1-2.



.



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__________________
1983 123.133 California
- GreaseCar Veg System

I haven't been inside one yet........so take it for what it's worth........

But, I'm making the assumption that you'll need a stiffer spring to resist the governor pressure that is controlling the 1-2 shift.

For slippery conditions, etc.

My friend's F350 can start in 1st, 2nd, or 3rd

-J

__________________
1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.

follow carefully:

Ease into the pedal..........very gradually..........and you won't spin the tires........even on snow.