WTB: W126 speedo part number 1265429901

[Don Andres]

My speedo gave up so I'm looking for a good replacement.

Found one, not looking anymore.

[upod]

Try garagistic...they have gears for the speedometer on w126. I have fixed many w126 speedometers with just a plastic gear.

[Don Andres]

Thank you but mine has some kind of electrical problem and throws off the entire cluster. I had another speedo but it’s km/h so the gearing is way off. It did solve the issues but speed reading so far off bothers me.

[Clemson88]

Sounds like a ground problem.

[Don Andres]

Originally Posted by Clemson88

Sounds like a ground problem.

Very likely but I haven't been able to find it. I admit I don't know much about how to fix speedos. I cleaned what I thought needed cleaning and checked wiring. Didn't make a difference.

Swapping the speedo for another one fixed that issue but it has the wrong ratio. Speed reading is way too low - km/h instead of mph.

Anyone have a functioning unit for sale?

[Frank Reiner]

DA:

What is the application, and what is the final drive (axle) ratio that is in the car?

[Don Andres]

Originally Posted by Frank Reiner

DA:

What is the application, and what is the final drive (axle) ratio that is in the car?

2.47 differential, 722.6 transmission and OM606 with mechanical IP

The speedo with part number 1265429901 will still be a little off because it is not a perfect match for the differential but we're talking something around 3mph where speedo reading at 75mph is actually around 72mph GPS reading.

I do not know if there is a better match available.

[Frank Reiner]

Originally Posted by Don Andres

2.47 differential, 722.6 transmission and OM606 with mechanical IP

The speedo with part number 1265429901 will still be a little off because it is not a perfect match for the differential but we're talking something around 3mph where speedo reading at 75mph is actually around 72mph GPS reading.

I do not know if there is a better match available.

DA:
This is an interesting situation; inasmuch as the 722.6 does not have provision for a speedo drive, what is the pulse source?
This is exactly the problem that John Roncallo has addressed in this thread:
http://www.peachparts.com/shopforum/mercedes-benz-performance-paddock/399988-connect-722-6-transmission-electronic-speedometer.html

[Don Andres]

Originally Posted by Frank Reiner

DA:
This is an interesting situation; inasmuch as the 722.6 does not have provision for a speedo drive, what is the pulse source?
This is exactly the problem that John Roncallo has addressed in this thread:
http://www.peachparts.com/shopforum/mercedes-benz-performance-paddock/399988-connect-722-6-transmission-electronic-speedometer.html

I do not know what the setup is, internal or external. I know that the OF Gear controller has options to use either. Perhaps I can adjust the pulse enough to make the speedo work. I'll see if I can read the current settings and take it from there.

I think the OEM W126 configuration had matched components that can't be adjusted.