Rough 3->4 shift in E53 4.8is (6speed) when cold
 

I've got a 2005 that shifts quite rough when cold but ONLY for the 3->4 shift. All other gears are fine, as is reverse. Additionally, it seems fine once it warms up. I still can't believe how smoothly this thing shifts (except for that 3->4), smoothest auto I've ever driven.

Also, if I am REAL light on the throttle, it will shift smoothly. If you have more than 30% throttle it bangs into gear like someone gave you tap from behind.

The fluid & filter has been replaced (allegedly, I can't verify this information).

So knowing all this, what should be my port of call to start troubleshooting?

Apparently, I've read that the harness problem is only on the earlier models, and since the fluid and filter have been replaced already, I guess that leaves the shift solenoids as the next (relatively) inexpensive part to replace.

Advice?

Reset the adaptations although it usually shows as 1-2 shift and makes you think that you've got an old Ford truck with a bad u-joint. This is what I did on my 2005 4.4i also check your clutch pressures before and after clearing and gearboxhttps://uploads.tapatalk-cdn.com/201...b6180de657.jpghttps://uploads.tapatalk-cdn.com/201...3db13dc186.jpghttps://uploads.tapatalk-cdn.com/201...35120b5f36.jpghttps://uploads.tapatalk-cdn.com/201...750c32d769.jpg

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From what I found with mine, that level of pressure variance means new solenoids are needed. Upper and lower limits should vary by no more than 100.

After resetting the adaptations pressures were fine although I also did a fluid flush and refill with new filters (fingers crossed) that it holds[emoji38] and I do have a couple of new (to me) solenoids for the future.

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Interesting. This site appears to have a wealth of info in it regarding these transmissions: Everything about your ZF 6HP26, 6HP19, 6HP28 transmission issues | BMW LOGIC7

How difficult is it to replace the solenoids? Just unbolt sump, pull filter out and go from there? Seems easy enough?

Interesting. This site appears to have a wealth of info in it regarding these transmissions: Everything about your ZF 6HP26, 6HP19, 6HP28 transmission issues | BMW LOGIC7

How difficult is it to replace the solenoids? Just unbolt sump, pull filter out and go from there? Seems easy enough?

I made a thread about it too. Search delay reverse and my name. Should come up.

Ok. Searching for “3 to 4 rough shift X5” brings up a ton of results on this board and others too. I think I’m gonna test the fluid level and make sure it’s good. People have replaced solenoids and it doesn’t appear to have helped.

Just gonna leave it.