Looking at the realities of the '82 not selling (and me having too much in it to drop the price any). Is there a benefit to grabbing the Diff and speedo from the '85 that's in the picnpull?

Most of my 130mile a day commute is 75mph. The CD has no problem doing it and sounds great, but I'd guess over 3k rpms isn't the sweet spot for economy.

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Eric, CPO, Submarines, retired.
Here's a sig line...
Mine: '68 Corvette LS1/4L65E, 83 240D, 2000 GMC 4x4, 08 FLSTC Anniv
Hers: '72 Corvette 454/4spd, '99 MB SLK, '93 Metro vert, 78 240D, '92 Silverado, '65 Fjord Rustang, '59 Fjord Fairlane, '17 Slingshot.

You can do some research into using the 247 as well as a couple of members have. It is a little steep but if that daily run is going to be the almost continuous service that car sees.

If the engine is in decent shape it can handle it.

Switching from 307 to 288 will not pay unless there is a functional problem with the 307.

You can easily pull the 247 if you have an automatic tranny.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

the big issue with putting in the 2.88 is expense of the parts. if you get them cheap from pnp, then it's a fine swap. snag the axles as spares while you are there. 2.88 is only going to drop your RPM slightly. 75 will still be near 3k (70 in my 201 with 2.65 is 2700)
if will make a difference, but not huge. MANY have said the 2.88 is the perfect gear for the 617a however keep in mind, that in addition to the diff/speedo change... 85's got a bigger cam, (slight HP increase) and a higher stall TC so the motor could rev higher before fully engaging the gears... gave the turbo time to wake up BEFORE pulling on the weight of the car...

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

If you got the 2.47 diff out of a 107 ( which I'm told is compatible) you would be turning about 2750rpm at 75. I almost never go that fast in my 617 powered 107 so that's based on an extrapolation on my known data point of 2200rpm at 60. I'll measure it today and edit this post if it's off. [confirmed]

Here's my actual mileage on the last coast-to-coast trip in October.



I'm using the 722.3 transmission with the 1700rpm stall convertor and the '85 617.952.

You'll likely see a bit less based on weight, aerodynamics and speed, but that would give you an idea of what to expect.

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Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica

Thanks for the info! Okey, well, I just checked inventory and it looks like I lost the '85 anyway, which was too bad as the car was 99% complete. They had put it in an area that was inaccessible to engine crane and very hidden so it wasn't picked over like the 82 SD there was.

Guess it hit their stay time and was crushed .

What were the 2:47 donor cars? Just W107s or were there others? Quite a few late 80's and early 90's gassers in that yard. Here's the current choices:

1984 Mercedesbenz 380se

1992 Mercedesbenz 300e

1989 Mercedesbenz 420se

1989 Mercedesbenz 190e

1996 Mercedesbenz E320

1993 Mercedes benz 300e

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Eric, CPO, Submarines, retired.
Here's a sig line...
Mine: '68 Corvette LS1/4L65E, 83 240D, 2000 GMC 4x4, 08 FLSTC Anniv
Hers: '72 Corvette 454/4spd, '99 MB SLK, '93 Metro vert, 78 240D, '92 Silverado, '65 Fjord Rustang, '59 Fjord Fairlane, '17 Slingshot.

the 380 is the only one with that diff I believe from that list.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

I agree, the 84 would probably have the 2:47. I pulled one out of a 85 380SE, so the 84 should be the same. look at the Diff on the bottom left corner. there are some numbers stamped in the metal. last 3 are the gear ratio.

The 126 spedo will not fit/work in your 123.

Also you will have to swap the yoke on the diff to the smaller one from the 123. the 126 uses a larger Flex Disk.

Diff up to 85 in the 126 will swap over to the 123, 86 - 91 the Sub Frame assy was changed as well as the Diff mounting.

Our 85 300D has a 4-spd swap, and 2:88, will hit 31 - 32 cruising on the Hwy. all depends on your driving and conditions. 29 - 30 would be the majority of the time.


Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

true.. any gen1 w126 will swap over to w123.... look for wracked gassers

mine is gen2 and I drove with 2.24 (ex500) after engine swap... quieter with less top speed....

.

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w126 500SEC gen II euro, powered by OM617 turbo stolen from 84 300SD 2.88 diff,EGR blinded
next wish/project: w114 coupe OM603 powered

this is very important... over here many have manual which they do not
include in equation...and suffer later

for example 2.47 on 5spd stick is a slow slow dog....


.

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w126 500SEC gen II euro, powered by OM617 turbo stolen from 84 300SD 2.88 diff,EGR blinded
next wish/project: w114 coupe OM603 powered

CHO, I notice that we could use a gear between 2 and 3, and 3 and 4 with this 2:88. maybe a 3:07 would work better. start dropping down to 2800 or so and feel her start to vibrate, hit 3rd and can run her up to 55 and smooths out.

I can see where a 2:47 could be a problem, all depends where you live, flat land vs hills etc... a 2:47 an automatic could work better than a stick.

Just my 2¢ worth.

I have a 2:47 I pulled from a 85 380SE several years ago when these 2:47 threads were popular. got all excited to get one. now just sits in the shop. spedo showed 201K.

Also have a 2:65 from a W116 6.9 with the clutches.


Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

At 75mph W123 aerodynamics are working against you in a big way. Even a 4spd manual without overdrive will eliminate a lot of drivetrain loss.

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CENSORED due to not family friendly words

well...as examined in vivo 2.47 & manuall is very slow to start and to make
enough umph to second gear..on the flat ground,..if you start on hill things get even worse....but when in 3rd or above ride is quite good

as for 2.47 & auto you can not notice significant difference starting on flat ground but on hills it is present but again,not so significant....umph on the hills may also suffer a bit

in my personal opinion,..if you are on 3.07 and swap to 2.47 you will notice
significant behavior change considering rpm's,noise on highway and some in consumption area. (for auto tranny)

for manual ... 3.07 is the optimal (well it is not...but mine is gen2 so I have no better options...)

so...om617a auto and 2.47... as a cruiser...yes. definitely.


cheers
ChO

.

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w126 500SEC gen II euro, powered by OM617 turbo stolen from 84 300SD 2.88 diff,EGR blinded
next wish/project: w114 coupe OM603 powered

Good info, thanks. I have a couple of Trade possibilities in the works on the CD, so I can't fool with it now, but I may pre-emptively check that diff at the picnpull and grab it if it's a 2.47...and the axles. Worst case the car gets gone and I have some parts to sell or trade.

Of course I'd have to find a speedo that I can adapt, or live with GPS as speedo.

__________________
Eric, CPO, Submarines, retired.
Here's a sig line...
Mine: '68 Corvette LS1/4L65E, 83 240D, 2000 GMC 4x4, 08 FLSTC Anniv
Hers: '72 Corvette 454/4spd, '99 MB SLK, '93 Metro vert, 78 240D, '92 Silverado, '65 Fjord Rustang, '59 Fjord Fairlane, '17 Slingshot.

I have an 85 123 with 2.88 rear , axles,and speedo. I do not have time to pull it. Talk to me if you might like it, and don't mind pulling it.

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1977 240D turbo