Should we provide for DD for Debts older than 270 days when we are already in process of repossessing the tractors and will sell at profit ?

From the question, I understand that yours is a financial entity dealing in loans as you have got the collateral security in case on non repayment of debt.

As per IFRS 9, the said loan is a "Credit impaired financial asset". However since the expected credit loss (loss allowance) is nil taking into account the value of collateral (truck), you don't have to consider impairment of this loan.

Interest also can be recognized on gross amount.

However as per IFRS 7, there is a need of disclosure regarding a) the entity's risk without considering collateral security b) loss allowance not recognized because of collateral.