GroundHawger said:
well when i bought this 84, it seemed like the fourwheel drive was working being that it was fulltime and driving. after i got it home, and was testing it out, i noticed that hi and low loc were not avaliable. and when i would put it in standard low, then want to put it back in hi. all it would do is grind. i was told to put another tcase in so i did. i put another one in, and all that one does is give me low loc, nothing else. i have 1 more tcase im gonna put in today. so hopfully that one works
The 203 is one of the most durable t-cases made but they do have some roughness to them. These t-cases are not shift on the fly capable. You can shift from hi to hi-lock or low to low-lock while on the roll but you need to go slow and you can't shift between hi and low on the roll.
Shifting between hi and low range requires a couple of different techniques. First you can try shifting the t-case by first putting the tranny in either park or neutral, or shifting to neutral or depressing the clutch, then shift the t-case. If the t-case doesn't want to shift, you may have some drivetrain bind. In this case you need to put the tranny in reverse and drive several feet and/or spin the tires backwards. Then repeat the above to shift.
Since this truck has been modified before, you should check to see if your front and rear axle gear ratios are the same. Make sure you also have the same sized tires at all four corners, and that they are all at the same pressure. If you have different sized tires, or have low pressure in one or more tires, or your front and rear axle gear ratios do not match each other, you can be experiancing severe drivetrain bind which will make shifting nearly impossible, and the problem isn't the t-case.
If everything checks out correctly, correct tire size and pressure, matching gears, and you do back up, you could have a worn chain or an out of adjustment, bent or damaged shifter linkage.
Ed
