This problem is noticed on 2002 Chevy 1500 PU.
In this check the fluid level in transmission.Is it low or getting leaked.
If the shift lever is very hard to shift into any gear then either the fluid needs to be changed OR there is an issue with the shifter fork assembly in the transmission.but if all gears it is just hard to shift without any gear clash changing the fluid usually would fix this problem.
The old dirty fluid that has lost its viscosity over the time.if you look in the owners manual it has how long before you should have it serviced.the clutch will not cause this problem.but dirty old fluid will cause all the gears to be hard to shift into.
It has a basic drain and fill system.You pull the drain plug let it drain put that back in then remove the fill plug and fill it untill it drips out of the fill then put the fill plug back in.Make sure they look up the correct fluid for that trucks transmission at the parts store.A lot of time wrong fluid viscosity will cause this exact problem.
Chrysler PT Cruiser only goes in First gear?
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Automatic transmission will not go into high gear?
Car won’t downshift sometimes?
Ford Taurus won’t shift from park?
http://schematicsdiagram.blogspot.com/2011/12/ford-taurus-wont-shift-from-park.html
Car Transmission will not go into Park mode?
Shift indicator directly goes to 2nd when key is turned ON?
Third gear missing and engine losing power?
Chevrolet silverado has whining sound in gear?
http://technoanswers.blogspot.com/2012/01/chevrolet-silverado-has-whining-sound.html
This problems are very common and noticed on many other car models too.
In this cases the gear shifting gets hard while driving.
But if you push the shift arm very tight the gears change.
This problem is noticed with Engine ON and not while engine is OFF.The gears shift normally whenb engine is OFF.
If the shift lever is very hard to shift into any gear then either the fluid needs to be changed OR there is an issue with the shifter fork assembly in the transmission.but if all gears it is just hard to shift without any gear clash changing the fluid usually would fix this problem.
This details will help you.
Thanks.
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See below latest solved gear shift problems :---------
Chrysler PT Cruiser only goes in First gear?
Car is stuck in park and the shift will not move?