Shifting issues on 1991 M30

[91M30]

My wife's 1991 M30 has a rather harsh 1-2 shift, but is slow to do a 2-3 shift or to lock up into overdrive; i.e., if throttle is held steady to hold RPM at 3000, it will not shift unless you back off very slightly on the throttle. The car only has about 60,000 miles. I've done a transmission flush and filter change, but it didn't change the symptoms. Any ideas as to what could be the cause? Speed sensor?

[Calvin_Q45]

Actually... My 1990 infiniti Q45 has that same problem right now... To shift from 1st to second.... i have to get the rpms up kinda high then let off the gas... and I honestly dont think it goes from 2-3 anymore... Also... i have notice that when driving highway speeds... if i let up on the gas... the rpms drop down to about 1000...

by the way... I just had a new transmission put in about a year ago... shifting problems... the shop said it was a cylinoid (sp?) problem...

I dont know...

[91M30]

BTT.....any other input?

[PalmerWMD]

Not much to write here...transmission is eitehr on the way out (llikely) or possibelk slow shifting due to restricted flow= low line pressures.

Solution:compelte transmission flush.Sometimes this is not enought to clean things out you may wanna bypass factory heat exchanger in radiator with a cooler ($50 part easy DIY).Not so much to prtotect transmission, as chances are most major heat induced damage has already occured but to make sure flow thru heat exchanger is not restricted.

If you shift imrpove after the above you saved your transmission, if they dont then there is litle that can be done ( at least there is no slippage)

Fred..