Good suggestion, but after hundreds of readings i have gotten good at reading the dipstick.
79, this is not about your ability to read the dipstick. We both know the dipstick reads high, and this could cost you a new short block when you come back to have consumption measured. Do not give the dealer an inch on this one.
The goal here is to perform a scientific, indisputable test so that you and the tech won't be arguing over an oily strip of metal. It's very simple. Get the dealer to accept these terms:
1. The dealer will at no time have unsupervised access to the engine bay. You will only leave the car when the hood is closed, doors are locked and keys are in your pocket.
2. 5.3 MEASURED quarts of oil will go into the engine after it is drained. Bring your own clear quart like I mentioned earlier.
3. You will not check or add oil.
4. After X miles, you will return to the dealership for the test.
5. Oil will be drained into a container that you will inspect.
6. The quantity of oil will be MEASURED in your presence. Bring that quart again.
7. A dipstick reading will not be used for testing.
This is not complicated. I've done it myself to produce very accurate consumption numbers. We have the technology. Get Rexy to agree, and get it done.