L3830 stuck in high gear

[Chaleo]

so my problem started a while back, when i would shift into low gear, it would not hold it would pop back out. you could hear gears grinding. but would stop and i would try again and it would hold a little while and pop back out. now it seems that the lever arm that switches high/low is stuck in high gear. makes it difficult to bush hog my fields. ive searched and found similar but not enough for me to open the tranny. can anyone help?

 

[North Idaho Wolfman]

I would thoroughly inspect and lube all pivot points on the range linkage, I've seen the linkage rusted up and/ or bent.