I think it's in the agreement. If the agreement says that you can remove yourself as co-maker for the loan then I think it's possible. But, most loan institutions I know don't have that option esp. here in the Philippines. So that before you sign as a co-maker, you have fully understood that whenever the primary signer couldn’t pay for his loan, the co-maker will be the one to pay for it. I remember one time, the comrade of my husband filed for a loan. The poor old comrade who was suffering with arthritis was the one he convinced to co-sign for him for his loan to get approved. Now, after he got the money, he went AWOL. The old comrade was so worried so he went to the primary signer’s home and begged him to return to his duty because his debt would be passed on to him. Poor old man. Good thing he returned but was demoted one rank lower. That is why I always tell my husband not to co-sign for any loan because it’s a big additional burden esp. when the primary signer doesn’t care for other people. It’s better now because some loan institutions here in the Philippines don’t require co-makers. So, before you sign any contract, read the terms and conditions because once you have signed them, you’ll be bound to follow what are stated in there.

Provided the other co-signer(s) agree, you still would need to convince the bank. You would need to provide evidence that the bank has sufficient guarantees for the loan, e.g. through an improved financial situation of the main signer.

Theoretically it is possible, but highly unlikely. You signed a contract to guarantee a loan for a reason. Normally that's because the primary signer has a weak credit profile. It is very unlikely the bank will let you out of the contract.