W124 5 speed gearbox swap question

[boomtings]

Hi,

My 93 300-24TE 5speed 722.5 still needs serious TLC, I have found a 94 320TE with a 5 speed, but a different part number.

Is a straight swap possible?
Or should I keep saving for a refurb.

Also Does anyone know what are the differences with the 722.501 and and 722.502 etc.

 

[Charles Morgan]

Some recent research shows each engine size having a different 5 speed box number, so I have no idea if they are interchangeable.

 

[Codger49]

Afraid I can't be more helpful, but I believe there were different versions for cars with and without catalysts, and also for cars with mechanical or electronic speedometers.

What's the fault with yours?

If its the skipping 4th gear issue, maybe only the 'controller' needs attention, not the main hydraulic/mechanical mechanism?

 

[Charles Morgan]

The other thing I learned from Nick Froome recently is that an ECU on a W124 with a 5 speed box was playing up and when substituted with the ECU from another 5 speed W124 which had a different engine, the 5 speed gearbox would no longer go into 5. As the 5 speed box was working perfectly in the donor car, it would appear that absent another fault it is possible that each ecu will only work with a gearbox for the same size of engine.

 

[boomtings]

Thanks for the input guys, I may just have to take the gamble as it appears to be very cheap.

My box has reverse gear failure and flaring on gear change.

 

[brucemillar]

Thanks for the input guys, I may just have to take the gamble as it appears to be very cheap.

My box has reverse gear failure and flaring on gear change.

Sounds like the clutch bands are about to give up. This is fixable from a decent autobox shop or a really good Indie. I had mine done by Andy @ Wright Tech. I had it done on a fixed price. Box in & out and refurb.

 

[Charles Morgan]

Certainly clutch bands but those 5 speeds do really have issues, flaring may not be cured by that and the money is then down the 15 hole alloys.

Heresy, possibly, but fit a 4 speed?

 

[grober]

http://www.w124performance.com/docs/mb/other/tranny_722_Mitchell.pdf

 

[Codger49]

There are quite a few threads about the 722.5 on the Peachparts tech help forum which may be useful information for you. Just Google on '722.5 Mercedes transmission' and the Peachparts results should be the second entry.

Can't post direct link as Google inserts my browser name into its URL.

This 2010 thread may help http://www.mbclub.co.uk/forums/engine/87161-legendary-722-5-gearbox-w124.html

ray_hennig still posts so a PM may bring info on his resolution. Otherwise, the 3 posts from the experienced gentlemen above indicate a replacement or full rebuild is the only real cure.

 

[boomtings]

Thanks for all the responses. I have downloaded lots of PDFs about the gearbox.

The 2010 thread refers to him using a w210 722.5 and transplanting it to a 300-24v. So at least I know I should be able to swap but may have some issues.

Thanks.

 

[darreningram]

I had reverse failure on my E280 5 speed which is the commonest problem with this box- I changed it for a 80000 mile box from an E320 and it has been sweet since- box was £500 and surprising easy to swap- so i was told my mechanic! Well worth buying a second hand box rather than refurb