Brakes locking when shifting transmission into gear

Clearly when putting the vehicle in gear, it should not affect the brakes, so I suspect it is not related to putting it in gear. I assume when you are putting it in gear, you have your foot on the brake. So, if that is the case they are just not releasing when you release the brakes.

So, I would suggest we start with lifting the vehicle and put it on jack stands. Then press the brakes and release them without putting it in gear and have someone go around and see which wheels are locked.

https://www.2carpros.com/articles/jack-up-and-lift-your-car-safely

The first thing we need to do is find out which wheels are locked, and which are not. Then we can make a better decision on where to go.

However, I suspect we have an issue with the master cylinder, but this is too early to tell.

https://www.2carpros.com/articles/how-to-replace-a-brake-master-cylinder

Also, did you change any of the brake components with this swap or in the recent past? Lastly, was this truck driving find prior to swapping the engine and transmission?

Let's start with this and go from there. Thanks

Clearly when putting the vehicle in gear, it should not affect the brakes, so I suspect it is not related to putting it in gear. I assume when you are putting it in gear, you have your foot on the brake. So if that is the case they are just not releasing when you release the brakes.

So I would suggest we start with lifting the vehicle and put it on jack stands. Then press the brakes and release them without putting it in gear and have someone go around and see which wheels are locked.

https://www.2carpros.com/articles/jack-up-and-lift-your-car-safely

The first thing we need to do is find out which wheels are locked and which are not. Then we can make a better decision on where to go.

However, I suspect we have an issue with the master cylinder but this is too early to tell.

https://www.2carpros.com/articles/how-to-replace-a-brake-master-cylinder

Also, did you change any of the brake components with this swap or in the recent past? Lastly, was this truck driving find prior to swapping the engine and transmission?

Let's start with this and go from there. Thanks