cant get trans into low range. diff lock works fine. dealer says i need some type of solenoid for $800.00 + labor. any alternatives or where i can locate a used or new one? parts houses dont show any listed.
Complete and utter B****cks from the dealer . All 300 series come with high and low range (via the transfer box). The Transfer box is the same bit of kit that makes the centre diff lock work. If it's a manual then you need to move the little lever (same one for diff lock) forwards to engage low range. If it won't go in try putting the car in gear and slowly lift the clutch whilst pushing on the lever. You should feel it engage. It may be that the linkages are stuck. In that case a good squirt of WD40 or similar and a little bit of work should free it off. I would not take the car anywhere near the dealer. Find a decent independant 4wd mechanic.
What the dealer is saying may well be legitimate. On 1993+ Range Rovers, there is a solenoid which prevents the transfer case from being shifted into Low Range when the truck is not in neutral on the transmission gear select (automatics) My guess is since this is a safety feature, the Discos have it too. It works on the same principle of not being able to shift out of Park (auto) unless key is on and brake is depressed.
BUT: There may be a cheaper way: All the solenoid is is a little electric valve which is either open or closed. If it is in one position, you can't shift into low. Tear the center console around the diff lock / hi-neutral-lo lever up and see if you can find the wiring to the solenoid. All you have to do is jump it and it is officially bypassed.
New 1996 Disco owner here. I am also having a hard time getting into low range. I am going to take it to a 4x4 mechanic to see what the problem might be. If you find any solutions to your problem, please share the info.