Can I lose my NCO rank if I go from Army guard to active duty?

Most likely will submit a grade determination waiver. Based on the needs of the Army will determine the rank.

No each deal is separate.

If your trying to go active from the MD Guard? Don't get your hopes up that you'll get your 368 even signed. I put in 3. 2 sat on some NCO's desk and never processed an 1 denied with no explanation. Than you try to ets and the recruiter tells you he stills needs a signoff from them but they won't sign off. It's not about your career, it's about their numbers. I could've left the military as an E6 minimum. But I made the mistake of enlisting with the Nasty Guard. Oh well

Most of the guys I've met while active that made this transition lost one or more promotions.

You have to go with in a year of receiving it

As I saw during my time in TRADOC, your tank will be in your contract. I saw a prior service SPC come in with a legit contract promoting him to SSG after AIT (not stripes for skills). Make sure it is in your contract and it's good to go.

Since army is similar, that i know of. In the marines, if you go from reserve to active you don't loose your rank but all of your points towards the next rank will start over.

Historically you would go down a rank, unless you are going into an E-5 slot.

This was some years back, but I almost went back to active duty from the CA ARNG. I achieved my rank in the guard not the RA. Although I did go to PLDC and BNCOC in the guard to be eligible for my rank. I was a 11B20 and would have gone back in as a 11B20. My recruiter told me I wouldn't lose my rank. Only time you can lose your rank is dependent on the MOS. Don't have a clue about now.

If you're just thinking about this and haven't done so yet, rather than proceed based on opinions, just go ahead and follow the advice many people have given and talk to a recruiter. You may find out that you cannot even get into active duty. The particulars about your current enlistment have to be examined and placed against current enlistment rules for Prior Service (PS) to join the Active Duty ranks. When I was recruiting I was difficult for PS to join, and when they did they always gave up rank. In a nutshell, you had to have gained it while Active, and they began deducting on a sliding scale based on how much time you've been out. Regarding getting it back, you have to meet the cutoff score after attending a board and being recommended for promotion. Look at the cutoff scores by MOS and you can judge the ease or difficulty of regaining NCO status.