john_boy

My recently purchased cream-puff (86K miles) is not upshifting into 4th gear. No matter how I coax it with subtle throttle deceleration at 50-60 mph it won't go up. (RPM at 60mph = 3100)
Transmission fluid is clean and full. It shifts normally into other forward gears & reverse. However, when first started up and shifted from P to R, it takes almost 3 full seconds to engage.

Have any of you solved this malfunction before?

Are any of you aware of a relevant posts on other models that may appy to my situation ?

Yes, I'm "price-sensitive" as to just taking it into my local import mechanic(s). I'm hoping it may be a sensor, or a shift band adjustment.

Thanks very much !

schwarzwagen

uh, actually that is 4th gear! It should tach right around 3k at 60mph. The car starts in 2nd gear, so under normal acceleration it only shifts twice, from 2-3 then 3-4. If you apply moderate to heavy throttle from a stop, it will engage first, or shift down to 2 and then back to D, to engage 1st from a stop regardless of throttle application.

john_boy

You are correct, indeed. I learned recently from a local M.B. mechanic those mph/rpm's are not a malfunction. He also informed me that if I wanted 1st gear to engage from a standstill, then I should shift from P to 2, then to D before accelerating. Or, of course, I could "manually" shift with the AT lever from 2 to 3 to D.
He said that transmission design was changed in 1991 due to owner complaints. I can acccept the design, but it's hard to think of my 300SE as a touring sedan when it's well above 4000 rpm on my local interstate (not autobahn). A heavy, safe town-car - perhaps.
When I expressed my disbelief about the 3000 rpm at 60 mph, the mechanic replied " Hey you should have bought a V-8".
Do you have any concerns driving many hours above 4000 - 4500 rpm ?

Regards, john-boy.

Paco

The M103 engine can run at 6,000RPMs (120mph) all day long and not have a problem, providing that you have taken good care of it. (oil, ect)