I leased a new vehicle for 7 mos . In the 8th mo, I terminated the lease and purchased a new vehicle. Both were used in part for business. Do I need a Gain/Loss Summary?

[KrisD15]

You will "dispose" the leased vehicle and purchase the new one. Enter the new vehicle as a new asset. 

You should have been taking the standard mileage rate for the leased vehicle, so you would have no gain/loss, only recapture the depreciation.  

For tax year 2019, depreciation in the standard mileage rate was.26 per mile