Rear window only cranks half way down

Hi All my rear window was cranking down a little hard sometime for awhile and I just wiggled the glass and it cranked down ok. Not it just stops half way. Any thoughts on how to fix?
Can I open the tailgate with window half way down to look inside?

Time for a complete interior rebuild of the tailgate.

I would suggest pulling the access panel and figuring out exactly what is stopping the glass from going all the way down.

I had one where an arm of the regulator was hitting a bolt and it wouldn’t go all the way down sometime.

Another with the end felt felt so bad it was in a wad keeping the glass from moving.

A third had the metal strip under the glass which is called the sash rusted to pieces and breaking off the glass. It was getting tangled in the regulator works.

Open it it up and check everything.

I had exact same issue with the guides on left and right. Removing access panel will show you the problem immediately and is simple to do.

/www.steelsoldiers.com/showthread.php?173878-1986-CUCV-M1009-Decade-after-being-wrecked/page39

Check out posts 382,383,& 384. I have more parts and side slide seal. Let me know. Good Luck. The rear gate is a crude antiquated POS if not properly maintained. Most are worn and rusted out at this point in time. They have been trouble since day 1. Check out post 379 & 380 also for side slide guide repairs without busting the bank and buying poor quality Chinese parts.

found out the left bracket is to close to the slide when taking it down. Not sure how to fix it but for now if I pull the window back towards me it goes down ok

It could be the regulator is jumping time and missing a few teeth or worn teeth to gear. It only takes a few slightly bruised teeth on the side levers to get a crooked window and make things difficult. Careful of inferior regulators. I had one pop right out of the package after a few cycles of up and down. Fortunately it was still in my possession and not back in the customers hands. I highly recommend a complete dis assemble clean and polish everywhere a roller or slide comes in contact. Then add wheel bearing grease to the lower sash guides, inside of window crank, regulator and anywhere you have metal to metal/nylon contact. No spray lube. Grease and oil. Real oil from a squirt can. I had the same M1009 for 20 years and used it hard. It was still working well when it was sold. Good Luck. Ask questions if you need to. And I have the guide seal replacement in limited quantities.