E-Class (W123) 1976-1986: 240D, 280E, 300D, 300TD, 300CD

722.3 to 722.4 transmission swap for 85 300d

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old Nov 27, 2013 | 10:19 PM
  #1  
KenWagner's Avatar
Thread Starter
Newbie
 
Joined: Nov 2013
Posts: 1
Likes: 0
1985 Mercedes 300D TurboDiesel Saloon
722.3 to 722.4 transmission swap for 85 300d

Good Evening,

I've had 2 previous Mercedes: a 97 E320 that I really enjoyed until a dumb kid ran into it. Then I had a 94 S320 that was great, but I was always dreading a very expensive part breaking, so I sold it.

I bought a 1985 300D Turbo-diesel saloon a few months back, but the first band on my transmission decided to wear out.
So I picked up a good used transmission from a guy near me inexpensively. Then I realized the transmission I have under all the grease is a 722.3, and of course since I'm in California, the transmission I have is a 722.4.
The difference for fit I see as the neutral safety switch. Both appear to have 4 prong connections.

So, a couple little issues to resolve, and please feel free to correct my assumptions.

1. Are there any other conversion issues I have to contend with?
2. I believe I will need a 722.4 safety switch to add to the transmission I have to make the conversion.
3. Is the electrical connector able to be changed out, or cut and re-wired to match the 4 connectors for the switch.
4. Or, is all this going to be a massive issue that I should just go back to finding a 722.3 transmission and sell off the 722.4?

Any other words of advice in this transmission transition?

Thanks, Ken
Reply

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


You have already rated this thread Rating: Thread Rating: 0 votes,  average.


All times are GMT -4. The time now is 12:33 PM.

story-0
New Electric Mercedes-AMG GT 4-Door Coupe Unveiled: 10 Things You Need to Know

Slideshow: Mercedes-AMG's new electric GT 4-Door Coupe trades combustion for software, synthetic noise, and more than 1,100 horsepower.

By Verdad Gallardo | 2026-05-20 20:08:15


VIEW MORE
story-1
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

Slideshow: Not every Mercedes design becomes timeless, some feel stuck in the era they came from.

By Verdad Gallardo | 2026-05-12 18:09:07


VIEW MORE
story-2
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

Slideshow: Yes, Mercedes built manual cars, and some of them are far more interesting than you'd expect.

By Verdad Gallardo | 2026-05-02 12:36:58


VIEW MORE
story-3
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.

By Verdad Gallardo | 2026-04-29 11:19:28


VIEW MORE
story-4
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

Slideshow: Before curves took over, Mercedes mastered the art of the straight line, and some of those shapes still look right today.

By Verdad Gallardo | 2026-04-25 12:05:49


VIEW MORE
story-5
Flawlessly Restored Mercedes 190E Evo II Heads to Auction

Slideshow: The 190E Evolution II shows how a homologation necessity became a six-figure collector icon.

By Verdad Gallardo | 2026-04-22 17:53:47


VIEW MORE
story-6
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

Slideshow: Mercedes is turning one of its core nameplates electric, and the details show just how serious this shift is.

By Verdad Gallardo | 2026-04-21 13:58:06


VIEW MORE
story-7
Mercedes EQS Gets A Major Update: Everything You Need to Know

Slideshow: Faster charging, longer range, and a controversial steer-by-wire system define the latest evolution of Mercedes-Benz EQS.

By Verdad Gallardo | 2026-04-15 10:35:34


VIEW MORE
story-8
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve

Slideshow: These overlooked Mercedes-Benz models never got the spotlight, but they quietly delivered more than most remember.

By Verdad Gallardo | 2026-04-13 19:35:45


VIEW MORE
story-9
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping

Slideshow: A well-used 1991 Mercedes-Benz 300D with more than one million miles is now looking for a new owner, and it still appears ready for more.

By Verdad Gallardo | 2026-04-10 10:05:15


VIEW MORE