W124 300E & 300E-24 RPM & Speed

[Lucas]

Hi, I recently bought a 1990 Mercedes W124 300E-24.
At this moment I have another 1986 Mercedes W124 300E.
The 300E-24 has a little noise in the rear differential and I'going to repair it.
Runningin in fifth gear at 3000 R.P.M. the speed on the 300E is 140 Km/h and the speed on the 300E-24 is 110 Km/h.
I would like to know what changes should be necessary to do in the 300E-24 to run at 140 Km/h in fifth gear at 3000 R.P.M.
Is it only a rear differential change or the gerarbox is involved?
What about the speedometer?
Sorry for my English and many thanks in advance.

 

[kid-jensen]

Lucas,

I'm willing to bet that the Axle is the only thing you need to change. The Haynes manual should connfirm that.....

 

[Rog_E]

You will also need to change the speedo drive as this will result in the speedo not reading correctly!