which speedometer?
 

hello community..
i have a 1985 300d, and i have replaced the 2.88 differential with and quieter 3.07 and need to calibrate the speedo to match. what are the numbers that need to be on the face of the speedometer? i have included a photo of mine, though they are wrong (the speedo that is).

thanks. chris

in case you cant read them....123 542 27 57

can anyone help?
thanks

Why is the 3.07 quieter?

according to my notes, you want the part number ending in 67 01. i may have a spare if you need one.

2.88
 

Where are you located, I am interested in you old 2.88 diff and matching spedeo.

I'm confused. Why would the speedo be different when (at least for any other make of car I know) you just change the speedo drive gear in the trans? It doesn't make sense to me to have different speedos to accomplish this calibration.

Dan

I also want to know why the 3.07 is quieter...

was there something wrong with your 2.88?

the 2.88 is coveted for it's economy, and silence at 70+mph... if yours isn't damaged, you could easily sell it if you wish.

nope.

the MB calibrates the speedo to the diff. all transmission drive gears are the same.

Is there a way to swap over the drive gears in the speedometer itself to another one? My brother is wanting to go to the 2.88 in his W116 300SD but there isn't much info on calibrating the speedo on the W116.

A quick way around this is - use a sat nav or gps to get the right speed .Remove the speedo lift the pointer over the end stop ,and move it a little at a time,anticlockwise.Then you can see how far it is from the right speed on the road ,trial and error. You should get it right.

how similar is the 116 speedo to the 123? could you use the 123 speedo in your cluster?

swapping the gears would only fix the odometer... the speedo is a slip effect design, so you'd need the entire mechanism...

If you want a 120mph speedo with a matching face as your original. You'll need a 123 542 18 57 from a 1983 model year or a 123 542 28 57 from a 1984 model year vehicle.

You can swap speedo gears and possibly mess with the magnet and spring a little bit. But acquiring the matched gears are a bit hard because closes would be a 2.65 ratio from a w116.

If you are able to get gears that are close, here is what I've done in the past.

http://www.peachparts.com/shopforum/diesel-discussion/238488-backyard-speedometer-adjustment.html


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