97 s320 weird shifting
 

hello-

maybe some of you MB gurus can offer advice.

we've had this car for about 5 years. now 157K mostly highway miles. meticulous service. had the transmission serviced with synthetic tranny fluid at about 90K miles about 3 years ago at MB dealer.

never a problem, no leaks.

now, the symptoms:

always when the car is cold it is sluggish to upshift into next higher gear. once warmed up it will shift normally.

now today it is sticking in lower gears intermittantly. of course we don't want to burn the tranny up. i tried to check the tranny fluid today and there's no dipstick.

now i suspect a problem.

the wife was able to drive it home. reverse gear works normally.

any advice, or am i looking at a 5K tranny rebuild?

thanks for any input.

RE: 97 s320 weird shifting
 

I believe your model is already equipped with "driver adaptive transmission module".
What that thing does is keeping higher revs between gear changes when the engine is cold.
So to some degree the symptoms might be normal.
At 157k the tranny might need rebuild, but I don't think it should cost 5 grands.
How far are you from California?

RE: 97 s320 weird shifting
 

Sometimes the air mass sensor can cause faults which appear to be a faulty gearbox too. Select a low gear and check if you can rev it to 5000 RPM while driving (not stationary). If it doesn't reach 5000RPM or is sluggish to get there, then it is most likely you need an air mass sensor. The air mass sensor tells the engine how much air it is getting, and because of the way that the gearbox and engine work so closely together, it can seem like a gearbox fault.
Hope this helps.