This morning my 1996 Discovery 300 Tdi automatic gearbox started behaving erratic. Would not change down, especially when going uphill. Very sluggish. On level the changing up seemed variable. Sometimes normal, other times not. Fluid level looks OK and clean. Has anyone any suggestions to solve the issue? Thanks

SOURCE: chrysler voyager automatic transmission problem

Sounds like you have yourself a bad shift solenoid pack this is mounted on the front of the transmission under a thick rubber boot and has an 8 or 10mm bolt holding a plug into it, these usually fail hot as it is an electronically controlled solenoid and there are tiny little springs and magnets inside that can stick also while you are in there do yourself a favor and change the two speed sensors on the transmission they are about $22 each and can also cause the problem you are explaining. the shift solenoid pack is about $120 on ebay and some sellers actually sell them along with the input and output speed sensors you may try changing those first and see if it solves it but i have a feeling your solenoid pack is failing also when you change these parts it may take the computer a few trips to relearn shift points but you'll know it fixed it right off the bat.. please rate and good luck -jeff

SOURCE: 2001 Buick Regal, 3.8L, 98,000

This happened to my 2001 Regal... There is a factory recall on the Catalytic Converter going bad. I had mine replaced with the recall and haven't had a problem since

SOURCE: not moving in any gear

Have you checked the High-Low ratio lever.  Half-way between High and Low is a Neutral, so no drive to any axle even if a gear in the main box is selected.
Try locking the differential.  If this gives you drive, then it might be a final drive (half-shaft) failure.

SOURCE: How to change the automatic gearbox oil - Seat - Cordoba - 1996

There will be a plug on the bottom of the transmission casing to let the old gearbox oil out.
On an automatic trans the filler is usually on top at the trans dipstick.
On a manuel trans there is a plug about half way up the trans casing.
Drain fully and put in correct type and amount according to your manual. Do not put any old trans fluid in use the type and quantity recommended by the manufacturer!
I find myself just going to a Quick Lube Shop and letting them do it for a few bucks more.. They get it right and it's faster than me doing it myself.

Hope this will FixYa!
jack

SOURCE: Sluggish steering - 2005 Toyota Sienna

You probably do have a power steering leak. Check the fluid again, it's most likely low if you are having an increasing problem with it. As the fluid is drained slowly through the leak it allows air bubbles to enter the system and cause it to become sluggish or sticky. Get the leak fixed asap so you don't spend a huge amount on fluid and keep an eye on the fluid level.