Is it a big deal to change my MOS when I go to MEPS?

Few things:
1. You are not committed to anything until you take your Oath of Enlistment and sign DD Form 4 (Enlistmemt Documents). Then is a bounding contract!
2. Your recruiter might get pissed of but that’s life, S/he’ll get over it. Make them work for their money, is your future!
3. As a reservist, you are limited by units based on your geographical location. That cool MOS you want might be available but 400 miles away!
4. As a reservist, once sworn at MEPS, that’s it! You are committed, no backpedaling from that moment!
5. Whatever your decision , make it quick!

Best of lucks on your future endeavors!

YES YOU CAN CHANGE IT!!! DO NOT TAKE THE 88M...If they're offering you that, then I assume your GT score is not a 110 or above...

Until you sign that paperwork and swear your oath you can change it.
Call your recruiter, let them know you don't want to be a truck driver.
If they say 'no'. Go talk to another recruiter...from the air force.

Things always change in the system, it is live, so if there is a slot available it can be seen nationwide. If you make it through, and you are both test, and physically qualified... you have a better shot at picking a job of your choice. I will say 15 series is very popular, as is 31 series jobs. My advice is don’t hone in on one specific job, as you’ll limit your chances of actually securing one. I’d say look at other 15 series jobs as well, 15R is not bad nor is 15U. Heck they even have 15W, which is a UAV operator.

88M is an OJT MOS... On the Job training... in the reserves gor some Prior Service... I Drove trucks all the time as a 19D and 11b.. see if you can guest at a Reserve or NG unit or Army airfield...and see both MOS' in action and talk to the troops.. Driving can be extremely boring... delay Enlisting...

BLUF - It's not to late to change your MOS. Don't let a recruiter influence your decision on what you want to do. I initially wanted to be Armor, but my recruiter said, "Well we don't have tanks, but I have something for you that is basically the same thing." That's how I started out as an 88M.

I wouldn't wait until MEPS to change your MOS. Pick the MOS you want, not what a recruiter is trying to push you in to. I would do some research/thinking on a couple things:
What MOSs does the Reserves offer
What MOS(s) do you want
How far is the nearest location with this MOS
How far are you willing to drive to get the job you want
How often do they have class dates for that MOS
How long are you willing to wait for a slot to open up

If it was me knowing what I know now, I would exhaustively look through the MOS list and read up on the ones that interested me. I would create a matrix with the MOSs that interested me and how far of a drive each one is, then I would call up the recruiter and give him your list and ask about class availability for each and mark those down. Then you can look at the matrix with all that information and make an informed decision.

Why haven't you presented this question to your current recruiter?

In any case, only answer I can provide is anecdotal. I'm sure another recruiter will see your question soon and be more helpful.

My wife enlisted back in 2010. She went to MEPS and was minutes away from taking her oath and swearing in. Suddenly, she gets a call from her recruiter saying that a new MOS has opened up that is really rare (12Y). "Geospatial engineer!" he says.

"Well, what is that?" She asks. "I don't know, it sounds they like build rockets or something," he responds. (No joke, that's what he said)

So, she thinks that's pretty cool and says yes. Then she gets pulled from the line to take her owth, fills out some new paperwork, and swears in. She's been making maps ever since. Kind of a glorified cartographer, only much cooler and intensely more complex.

Also, I was told that since I'm a reserve, some MOS's or units might require a interview. Can anyone give some insight on this?? Obviously, if I do have to go through an interview, I will treat it like any other interview but just not sure what to expect from it.

If I were you I would tell them you're waiting until 15T opens up. Mid-September is usually a good time...that is just prior to the new fiscal year.

YOU CAN ALWAYS RETAKE THE ASVAB!!! don’t let them foul you and tell you can’t ! If your not happy w your scores study harder and retake!! I got stuck w my MOS because I didn’t know I could retake . I am currently taking a class to raise my GT score so I can finally change my MOS . Is your life & your career !! Hooah!