when I move the gears to Reverse, Drive or L for Low it just shakes hard for 5 seconds then shuts off with my foot on the brakes?

Hi,

It sounds like you could have an engine vacuum leak. The power brake booster is actuated with engine vacuum. Since it is affected when you use the brake, that is where I would check first.

If you look below, I attached a picture of the brake booster. It is mounted to the firewall under the hood/driver's side. The brake master cylinder is mounted to the front of it.

I highlighted the vacuum hose. Inspect it to make sure there are no leaks or damage to it. Also, with the engine running, have a helper press the brake pedal while you listen for a possible leak around the booster. If there are none, follow the directions in this link to see if you can locate a leak at a different point.

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Let me know what you find.

Take care,

Joe

See pic below.