The car is community property. You have the right to manage community property during the marriage. If you purchase another vehicle and trade in the community property vehicle, the value of the old vehicle will still be community property. The new vehicle may not be community property if he has filed for divorce as the filing will terminate the community property regime retroactive to the filing date. If he has not filed, the community property regime is still in existence and any vehicle you purchase will be community property. He may not be able to take the new vehicle from you but you may owe him 1/2 the value of the community property vehicle that you trade in. The answer is that you can trade in the vehicle.
Every situation is different and you should consult your own attorney to go over all the particular facts in your case. The answer give in only intended to provide general guidance regarding rights and responsibilities.
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