1989 Mercedes-Benz 300 SEL – Internal Transmission Problem

Reader Question: Dear Honest Mechanic,

I have a 1989 Mercedes-Benz 300 SEL. On the original window sticker that came with the car new it says that the car is equipped with a 4 speed automatic transmission.

The problem is that I have counted over and over and I can only count the transmission shifting 2 times from 1-2 and from 2-3. When driving down the freeway at 65 MPH the cars tach shows rpm of 3500, which seems high to me.

Is there something I can do or is this the way it is supposed to be?

Thank You.

Don

Hey Don,

It does sound like you might have a transmission issue. At 65 MPH, I would expect the tachometer to read about 1800 RPM. I do not know what to tell you to do expect find a transmission shop that is experienced in Mercedes and get them to run some tests to see what the problem is.

I would suspect you have an internal transmission problem, so make sure you get a worst-case overhaul scenario from the shop before they disassemble anything.

Blessings,
Austin Davis

2 Comments on "1989 Mercedes-Benz 300 SEL – Internal Transmission Problem"

Trackback | Comments RSS Feed

  1. Aaron Lucarelli says:

    If your transmission is shifting and your at 3500 at 65 then its probably working ok. The forth gear on these is a 1 to 1 ratio which is why it has high rpm at those speeds also the transmission starts out in 2nd then 3rd then 4th 1st is obtain under heavy accelerations and during decerations only . Also there is no converter lockup, which would also bring the rpm down a bit

  2. Aaron Lucarelli says:

    If your transmission is shifting and your at 3500 at 65 then its probably working ok. The forth gear on these is a 1 to 1 ratio which is why it has high rpm at those speeds also the transmission starts out in 2nd then 3rd then 4th 1st is obtain under heavy accelerations and during decerations only

Got Something to Say?