Hard shift manual transmission

Put some transmission conditioner in and run for awhile, could be a sticking spool in the valve body from shellac buildup.

Probably needs a good flush and new filter

It is an adjustment or clutch replacenment issue. Manual transmissions rarely have a lube issue unless you have seen a big puddle of very thick oil in the driveway.

I think I'd be looking at the clutch of this 16 year old vehicle. Unless you have the tools, time and skill to change the clutch, this is probably a job better left to a professional. Adjusting the clutch mechanism might help for a while but I think you will soon need a clutch job on your GMC.

Thanks for your question at FixYa.com

Transmission does not shift automatically, only manually. Swap in a known-good PCM, check wiring, check other sensors such as VSS and TPS.

Trans shifts into gear harshly, car feels sluggish off the line, No 1st, 4th or TCC lockup available, Manual 2nd, 3rd and Reverse are only available gears, CEL is on: Transmision is either in limp-home mode or has lost electrical power. If there are lots of error codes in the PCM, check the underhood fuse that powers the transmission, and if it pops again, look for a short in that circuit like an O2 sensor harness touching exhaust. Otherwise, check PCM codes for a particular fault in the transmission causing the PCM to put it in limp-home mode.

Car goes into gear but feels very sluggish like the brakes are dragging, but it will roll easily (starts out in 4th gear), you manually shift to 2 to get it moving, once it's moving you put it back in OD and the car shifts 3rd to 4th on its own and locks the converter at the appropriate time: ShiftB solenoid failed: Easy fix in the pan. Or a wiring problem from PCM to trans.. or PCM.

Good luck and get back to me, hope this helps.

Your problem likely resides with the hydraulic valve that operates the band for second gear, or lack of hydraulic pressure in the transmission. If the actuator in the transmission that operates second gear is getting sticky, then it will cause this. A filter change and flush may help, but it's likely time to start looking for someone to tear down your transmission, or replace it.

You always add transmission fluid while the car is at running temps because transmission fluid expands when it's hot.

Computer! The transmission 4l60E is electronically controlled .

I have the same problem with my 97.... especially shifting from 3rd to O/D... I've had the tranny serviced and flushed.... It still does it until the tranny warms up.... the tranny's in them are temperature picky!!!!! It's the nature of the beast!!! Wait until spring and everything will be good until next winter!!! If you're really concerned with it you can put a "cold front" on it or block half (NO MORE THAN HALF) of the tranny cooler with cardboard thru the winter months

no power stuck in 3rd gear electric shop unless youve burnt it up good luck...www.TransmissionGarage.com

i gather its an auto transmission ,which mean your loosing oil pressure from the convertor inside the tranny housing.