I was a level 89 when my rank got reset. But I had a backup file and recovered everything including my skins and dlc characters, everything. Here's how to do it:
You have to have a Usb drive (doen't matter what size).
Plug it into your xbox 360.
Go to "System Settings" and select "A" button,
Move down to memory and select "A" button,
Select the xbox's Hdd and select "A" button,
Click on "Games",
Move down to Gears of War 3 file and click "A' button,
There's all your skins, characters and player data...
*Note - You can't copy or move your "player data file", I'll tell you how in a minute..
On to copying your files, Select the Item you want to backup and click the "A" button..
It will give your 3 choices, 1) Copy 2) Move 3) Delete, "CHOOSE MOVE"!!!
It will now ask you Where you want to save the item, choose the usb drive you just plugged in.
DONE!!! It's that simple!! It is now saved and safe.
Do this for each item you want to backup.
"Do not choose MOVE or it will move your file to the usb and you'll have to select that as your hdd everytime you play gears.
Always choose "Move".
How to copy the "player data file". Really simple.
Boot up Gears, select your Usb drive that you just saved everything to and "play" 1 game of anything. When you're done playing, Go to the Dashboard and your "player data file" is now copied onto your Usb drive and you are now done completely backing up all your gears files.
Rank got Reset/How to recove
If you get your rank reset or loose an item, just plug in your Usb drive and boot up Gears and when it ask you to select the Hdd to save to, select your "Usb drive" and everything will be back to what you saved on the usb. All your skins, characters and rank!!! Play 1 game of anything again and when you're done, go back to Gears main screen and change your storage device back to the Xbox 360's Hdd (storage device) and when it downlads the content, you will have all your items and rank back on your xbox's hdd again and you have successfully recovered all you stuff.
After you finish playing gears for the day, I highly reccomend you save everything you've done to the usb drive (only takes a few minutes). If you get to level 90 and get reset and the last time you saved the game was at level 85, then that's what your rank will be, level 85. Better safe than sorry. Always save your files to the usb after you're done playing for the day.
This saved my butt from going back to level 1 and hope everyone heeds this warning..
Any questions, just leave them here...