2004 SL500
 

I have a 2004 SL500 with @ 8K on it. The 7 speed automatic shifts poorly. Mercedes claims that it was designed that way but I don't think so- they did a flash on the software but it did not help. When it shifts to a higher gear it overrevs @ 200 to 300 RPM before finally locking in. Its embarrasing! My GMC pickup shifts better. Any ideas?

RE: 2004 SL500
 

it isn't much.

hard to tell without drive testing the car. the shifting should be smooth and un-noticeable.

RE: 2004 SL500
 

Check the fluid level.

Might be a modulator pump adjustment could resolve it.

RE: 2004 SL500
 

Or try my old trick. dicconnect the battery for 30 minutes at the ground this will set the ECU back to default. See how the transmission operates then. If the same it might be the module?

RE: 2004 SL500
 

A little quicker method: Disconnect both cables and touch together for 30 seconds, then reconnect.

RE: 2004 SL500
 

Won't that short out the electrical system or at least blow the fuses to kingdom come?

RE: 2004 SL500
 

No. Just make sure both cables are disconnected before touching them together.

RE: 2004 SL500
 

A new service info was just issued today on 722.9 shifting problems. Involves a look at shift adaptation and possibly a loose clip in the trans. Trans shouldn't flare when it shifts. You need to take your car in and have this done. If the tech can't get the trans to perform correctly he should call the EDAC hot line and get a trans, or valvebody authorized.