If it is automatic you have problems. If it is standard you still have problems. Put some Transmission Fluid in it then if it still "slams" you need a new transmission.
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The transmission is not slamming itself yet you are experiencing the gear drop in rather hard inside the casing. Check your transmission fluid level and make sure its full. Also check the consistency and color of the fluid to see if it needs to be changed (filter also will need to changed).
I had an old Pontiac do this very thing and it was because it was extremely low on trans fluid. - jedgell233
When you have problem shifting gears, you transmission has a problem.
Manual transmission is when you use the shift stick to shift to different gears in a car instead of driving without shifting gears,which is auto transmission.
Shifting forks.They slide the gears along splines engaging them to another gear.
If the 1997 Nissan Altima with an automatic transmission is shifting gears too early, it could be that the shift solenoid for the transmission is faulty. Both the shift solenoid and the speed sensor on the transmission should be checked.
if you dont hit the clucth and do it you are just slaming it into gears or you are torking it to hard
try the transmission ouput speed sensor
An automatic transmission might be slow shifting from first to second because of low transmission fluid. You might also have damaged the gears in the transmission at the area between first and second.
Shifting gears without syncros in your standard transmission would be anything but easy.
Are you sure it is the transmission that is clunking? It could be the u-joints on the drive shaft that are making the noise. When the u-joints on the drive shaft are bad, there is an audble clunk when you accelerate and when slowing down (basically the same motions you go through when shifting gears).
A body lift can interfere with the shifting of gears.A body lift can interfere with the shifting of gears.
A "speed" sensor can affect the shifting of the trans.A "speed" sensor can affect the shifting of the trans.
A sign of low transmission fluid in a vehicle is the gears not shifting properly. Transmission fluid can be checked to determine the level of fluid in the vehicle.