I'm a bit surprised, myself.

Thanks for your support, Paul.

Oh, Brian; I thought of one more caveat. I believe on the 722.3 tranny that 1st gear brings the B4 clutches into play, just as it does when shifting into reverse. These clutches are the first thing to wear out in this tranny, just from shifting to reverse in normal use. If the car started in 1st every time, it might mean engaging the B4 clutches much more often. Could this be a possible wear issue? Perhaps not, as banging into reverse from Park or Drive probably puts much more slip on them than downshifting from a forward gear (2nd) when slowing down. Just an observation, certainly nothing that should halt the project. And those clutche plates are relatively easy to replace - if of course you have the tranny on the workbench.

DG

Spoke with Silver Star Transmissions.

Very knowledgeable fellows and advise that you cannot use any of the later 722.3 transmission ('91 or '92) with first gear start. There is a misalignment with the case and the unit won't last 100 miles, although it will bolt in just fine.

The recommendation is to find a valve body from a 380 (722.310 trans) which had first gear start and matches perfectly with the existing trans.

I've spoken with them on the phone too, and found them to be very professional.

-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.

Very professional but the advice is in opposition to the comments from European transmissions which states that all 380's also started in second gear...........and that the valve body modification to the governor pressure valve is all that is required to get first gear start.

The differences in opinions is striking.............

Wow, scary news. Brian, I'm a bit confused. I have the '91 with a 722.3 tranny that starts in 2nd. Are you saying some of these start in 1st?
Or are you saying that they cannot be modified safely for 1st geat start?
What does your car have - I assumed the same 722.3?

DG

Who knows, maybe it's the 722.310 that actually doesn't line up quite right and the guy you spoke to forgot to eat his Wheaties.

Another option would be to buy a suitable 722.3 car that you can drive and verify that its got FGS. Then transplant the entire transmission into yours. Put your 2nd gear start tranny back into the other car.

__________________
http://i193.photobucket.com/albums/z...-RESIZED-1.jpg
1991 300E - 212K and rising fast...

Let's just say that I have no confidence in any of the information received to date.

Reviewing it isn't going to gain any confidence.

I'm trying to get some confirmation regarding the simple valve body modification to move the spring in the governor boost pressure valve............

If I cannot get that............I'm going to purse one of the diesel valve bodies............which I'm quite sure will work fine...........although one of them also stated that the shift points won't be right.

An update:

I found a 2.47 diff over in NJ for a decent price. Try to get it this weekend.

Silverstar in OK has agreed to put the 722.3 V8 valve body on the dyno with the spring relocated on the governor pressure spool valve to determine if it will give first gear start, as claimed.

We'll see..............

Awright! Making progress.

One update:
As you know, when stone cold our cars will start in 2nd, and hold 2nd until the engine warms a bit. Out of curiosity, I manually put the car in 1st gear start when first leaving the house the other day. Just wanted to see if it would hold 1st or 2nd until warm. It quickly shifted to 2nd under light throttle, just like when warm, then held 2nd for a little bit, as usual.....but, man, that first 1-2 shift was harsh, not at all as smooth as when warm.
Just another input to chew on. With taller gearing it might not be so sudden, or a little modulator adjustment might smooth it out.

Keep us apprised.
DG

Thanks.

I'm aware of that 1-2 harsh shift and I want to correct that issue when the valve body comes out.

I would really like Silverstar to take the lead and perform the necessary modifications, which I'd gladly pay them to do.

They have a dyno...........so it's not going to be a blind hope that it does what we want it to do.

We'll see.

It's not a priority of theirs..........for sure..........so I might need to be patient.

Gives me time to the the 2.47 and speedo installed.

The sudden impact of that 1-2 shift with a 2.47 is going to be absorbed by the flex discs....

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

No........it isn't.

Firstly, the 2.47 is going to minimize the "sudden impact".

Secondly, I'm going to modify the valve body with the spring change to soften the 1-2.

But, thanks for another post that doesn't have any data to support it.

Hi Brian,
it has been very interesting reading all the comments. You are correct in what you say about the ratios, so I am absolutely waiting to see how you go. I have a 1991 300SE and it always starts in 1st gear. My previous W126 was the 420SEL and I got an electronic control unit from a guy in Ireland for around $200 and it worked very well. It used the ABS pulse for speed to change gear. You could adjust when you wanted it to change.
I will be waiting to see how you go Brian, best of luck
BrianD.
Ps.
420SEL does not have that much power, my old Jag used to run rings around it. (;-)

Another tidbit of valuable info..............the '91 starts in first gear. That's the first I've heard of that point. I wonder if it's the same here in the US? Somehow, I doubt it.

Do you know if the '91 has the 3.46 diff installed? If so, first gear would be very short.........to the point of being useless in everyday driving.