If it is a manual transmission then broken mounts are always a good place to start looking next is a clutch problem nor disengaging properly--again a mount problem if it is an auto the the mount is immaterial as it will be a selector sensor problem
The best thing you can do is beg, borrow or buy a OBD (on board diagnostic) reader and check what DTC (diagnostic trouble codes) you have ...
Which one (reader) is an entire area of independent research... so keep your problem focus (keep your first one cheap & easy)... all you want now are your DIAGNOSTIC codes ...!!
I got into this simply because there are a ton of reasons for "harsh shifts"... most probably after 12 years of faithful service... folks reward their car with leaving the original ATF UNCHANGED...
A huge area of general discussion causing HARD shifts is your idle air control valve (TPS: see below)... (fuel injection system = idling high).
BBB Industries has an excellent TSB ... 4 on your tranny (Technical Service Bulletin. registration required)...
Only AFTER you have checked your engine speed & refreshed your tranny fluid... a little CLEAN ATF can work wonders!!
Hope you find this helpful.
Throttle position sensor http://www.rockauto.com/en/catalog/lincoln,2004,ls,3.9l+v8,1426137,fuel/air,throttle+position+sensor+(tps),5136
Hard shifts could be the input or out put speed sensors on the transmission. Both would throw an engine light. Mounts can cause hard Shifts, but get light as the gears change. Would wouldn't feel it from 3rd to 4th. For the shifter. It could be the shifter is really dirty, the solenoid in the shifter(replace the shifter), wiring, the ignition switch solenoid, or the brake pedal switch.
Answers & Comments
If it is a manual transmission then broken mounts are always a good place to start looking
next is a clutch problem nor disengaging properly--again a mount problem
if it is an auto the the mount is immaterial as it will be a selector sensor problem
Hello Roger Jones
You have 4 Technical Service Bulletins (TSB)..
The best thing you can do is beg, borrow or buy a OBD (on board diagnostic) reader and check what DTC (diagnostic trouble codes) you have ...
Which one (reader) is an entire area of independent research... so keep your problem focus (keep your first one cheap & easy)... all you want now are your DIAGNOSTIC codes ...!!
I got into this simply because there are a ton of reasons for "harsh shifts"... most probably after 12 years of faithful service... folks reward their car with leaving the original ATF UNCHANGED...
A huge area of general discussion causing HARD shifts is your idle air control valve (TPS: see below)... (fuel injection system = idling high).
BBB Industries has an excellent TSB ... 4 on your tranny
(Technical Service Bulletin. registration required)...
Only AFTER you have checked your engine speed & refreshed your tranny fluid... a little CLEAN ATF can work wonders!!
Hope you find this helpful.
Throttle position sensor
http://www.rockauto.com/en/catalog/lincoln,2004,ls,3.9l+v8,1426137,fuel/air,throttle+position+sensor+(tps),5136
TCU
http://www.rockauto.com/en/catalog/lincoln,2004,ls,3.9l+v8,1426137,transmission-automatic,automatic+transmission+control+unit+(tcu),8480
Hard shifts could be the input or out put speed sensors on the transmission. Both would throw an engine light. Mounts can cause hard Shifts, but get light as the gears change. Would wouldn't feel it from 3rd to 4th. For the shifter. It could be the shifter is really dirty, the solenoid in the shifter(replace the shifter), wiring, the ignition switch solenoid, or the brake pedal switch.