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well winter is here, took my euro down to lexington where it will be garaged for 4months. after seeing the underside of my durango thats seen 2 ohio winters the euro will never see snow. i've got paint bubbling on an '05 :wtf:

back to the point, i'm looking to change up the gear ratios of my euro to make it feel sportier and less like a big 80's coupe. i've got a cousin whose ASE certified and a tool and die maker who thinks he can fab up a 3.73 differential in it. we also talked about swapping in a 5speed but don't know what transmission would work well, there's no way ill fork over $4-5k for a ford racing transmission which was his idea. are there any close-ratio transmissions made by mercedes? This is all well beyond my mechanical ability, and he doesn't know anything about mercedes so any suggestions?

anyone know the transmission and diff. ratios of a 500sec euro??
 

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1991 w126 420SEL, 1986 w126 Euro 560SEC (option 822), 2000 E55, 2003 E55, 2003 SL55
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I know for sure you can crawl under the car and look at the tab on the bottom passenger rear facing lower side of the pumpkin and the diff numbers will be hand scrip'd in. Mine was covered in grime but when cleaned said clearly 2.65
 

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87 Euro500HVSEC. 88 Euro 560HVSEC. 89 Euro 560HVSEL
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My 87 Euro 500SEC is 2:27
It seems common with the series 2 Euro 500's and tall gearing must have been for high speed cruising, but also the came with 1st gear start which compensated off the line)

My parts car an 86 Euro 420SEC has an LSD 2:47 which iam going to rebuild (new seals etc) and fit which should help a bit.
 

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2012 CL550 4MATIC Coupe
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If you can find a 722.350 transmission, it has a 3.86:1 final drive. That is what's in the Jack Middlebrook SEC and what I am looking for now. The .350 is the Euro transmission and has a "Snappier" feel from what I read.

Also, a more complex grafting would be to get a 722.6 as Jono suggested, but you would want to do a full rebuild on it and also it is more complex to graft in because it is electronically controlled with its own ECU and it needs inputs that the 722.3's do not and therefore would bee to be grafted in. This weekend I am going to go and rebuild one, so I will get to see inside firsthand. I will report back.
 

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87 Euro500HVSEC. 88 Euro 560HVSEC. 89 Euro 560HVSEL
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Hey Mike, way to go whooaa - stuff the diff, just swap the trans out (you dont muck around). what diff ratio will you be running with that? your going to need a good LSD to ensure all that torque gets to both wheels.
Black rubber off the lights will be the norm from you be warned.

I thought the easier path would be the 2.65:1 LSD diff swap that DBMB luckily has.
Is that crown wheel hard to source on its own and where?
 

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'87 560SEC: '86 AMG 560SEC: '87 560SEL - PAST: Heckflosse 190 & 230S
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If you can find a 722.350 transmission, it has a 3.86:1 final drive. That is what's in the Jack Middlebrook SEC and what I am looking for now. The .350 is the Euro transmission and has a "Snappier" feel from what I read.
Hey mclare - I must be misreading your post cuz aren't the trannys in both your 560's are already 722.350 (post MY '89)? :confused: Or was a .323 put in when you did that swap at the JY ?

I guess what's meant is that a 722.350 euro trans is different (Euro unit was shorter 1st gear ratio (3.86:1) and a spot for the reaction valve circuit (which communicates with the EZL for faster shifting).)
 

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1991 w126 420SEL, 1986 w126 Euro 560SEC (option 822), 2000 E55, 2003 E55, 2003 SL55
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I could not verify 1st gear this but the transmission in my 560 Euro is a 722.323 and seems very short but it may be a difference in the diff. ratio that I am feeling compared to my other car.
 

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Depends on the day!
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The .6 is a great transmission, swaps are pricey, namely getting the TCU tuned properly takes Time. Figure you'll have about 1500 or so in the TCU and tuning. Another 2K @ least in the transmission..more yet for the custom drive shaft, mount and what ever ancillary problems that show up.

With that you Could run a 3.27 quite comfortably, the 0.78 OD is Great.

As for a manuall box from benz, I'd give up the hunt now.. look to BMW for a trans, they have Far more option if manual is the way you want to go and stay German.


Btw, if someone is looking for a Euro AT w/ the 3.86:1 I've got one w/ 36K on it sitting on the shelf:)


Jonathan
 

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87 Euro500HVSEC. 88 Euro 560HVSEC. 89 Euro 560HVSEL
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Hey mclare - I must be misreading your post cuz aren't the trannys in both your 560's are already 722.350 (post MY '89)? :confused: Or was a .323 put in when you did that swap at the JY ?

I guess what's meant is that a 722.350 euro trans is different (Euro unit was shorter 1st gear ratio (3.86:1) and a spot for the reaction valve circuit (which communicates with the EZL for faster shifting).)
Interesting- If Mike was going down the Euro 350 path to get the 3.86:1 1st gear ratio, does that also mean the specific matching EZL for the snappier shifting function as compared to the US 350 /EZL?
 

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Discussion Starter #10
The .6 is a great transmission, swaps are pricey, namely getting the TCU tuned properly takes Time. Figure you'll have about 1500 or so in the TCU and tuning. Another 2K @ least in the transmission..more yet for the custom drive shaft, mount and what ever ancillary problems that show up.

With that you Could run a 3.27 quite comfortably, the 0.78 OD is Great.

+As for a manual box from benz, I'd give up the hunt now.. look to BMW for a trans, they have Far more option if manual is the way you want to go and stay German.


Btw, if someone is looking for a Euro AT w/ the 3.86:1 I've got one w/ 36K on it sitting on the shelf:)


Jonathan
Ah, good to know. if i can't get an MB manual then i really don't care what goes in it. i'd like atleast a 3.3 rear end. the '05 durango has a 3.55 and sucks *ss on the highway. granted my euro has my HP then it. this is going to completely kill the value of my car. but ive been stopped countless times by old men talking to me about the car, only to turn their noses up when they see a 7inch touchscreen headunit:D. granted only old men(no offense) give me compliments. only time ive been pulled over is doing 50 in a 35 and got off because the guy loved my car. anyone else been followed by cops? happens to my all the time. you'd think i was in a porche:cool:
 

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2012 CL550 4MATIC Coupe
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Yeah,I think I have a .323 in there now from the swap last year, and of course I left the old one at Dragi's and that ship has sailed. I will check when I pull the motor/trans next week. But I am expecting it's a .323 in there. Maybe not?
 
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