1990 740 Turbo AW71 shifting late/slipping

Now that my 745T is up to driving conditions and I've put a few miles on it to make sure everything is tight I've done a couple of WOT pulls. What I have noticed is that from 1-2 and 2-3 the RPM's will reach about 5500 and then the engine will rev really quick for a second before it shifts. It's like it hesitates to shift and revs up during the process. Is this indicative
of a slipping trans? The fluid level is good. One of my last couple of to-do items is the transmission filter change and fluid flush. I wonder if this will help this issue. Thanks.

sounds like a cable adjustment issue. too tight will make it shift at high RPM
loosen it up a bit see if that helps

The throttle cable or the kickdown down cable? The kickdown has about 1cm play at idle. Maybe a bit less.

kickdown, but if it is that loose already idk some other issue with trans

Kickdown cable too tight would make it shift late under part throttle but it sounds like your issue is flare on WOT shifts.

What does the fluid look and smell like now?

Could be a clogged/loose filter or poor fluid quality, give it a thorough service and see what that does. I like to start with a pan drop, change filter and exchange what's in the sump and then do transfusion method with cooler lines to get fresh fluid throughout the trans.

If it's shifting slowly on WOT gearchanges take it easy on it until/unless you sort it out, you might have a problem you can solve now but if you keep hammering it while it's behaving that way you will cause real damage.

drift256 said:

The throttle cable or the kickdown down cable? The kickdown has about 1cm play at idle. Maybe a bit less.

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When you say 1cm play do you mean the cable has 1cm slack?

It needs to be adjusted for some preload, there should be no play or slack in the cable. The marker block on the cable should be a few mm out of the end of the threaded housing end. If it has any slack in it at closed throttle then it's too loose, which will result in sloppy shifts under hard acceleration and damage to the clutches.

Find and follow the greenbook procedure for setting the kickdown cable if you don't have a feel for how this should be, and see if it requires you to make adjustments.

Thank you fellas. Yes this kick down cable has some play at the throttle body. I wasn't sure how tight it should be. I ordered a filter and gaskets so I will do the service and flush and adjust the cable and see if that solves it.

Finally got my driveshaft back in after replacing the carrier bearing. I adjusted the kickdown cable to factory spec. It was so out of adjustment I had never felt the detent in the pedal and I don't think I was even getting WOT. Shifts much better now and at more appropriate times. Doing the trans filter and flush this weekend. Thanks guys.