Ford Repair: engine lock up, ford focus zx4, warenty

Question
My daughter purchased a new 2005 Ford Focus ZX4 with a 2.3L engine about four months ago. The car has 7200 miles on it. She should have had her first oil change at 5000 miles but she neglected to do so. Yesterday her engine locked up and it was towed to the selling Ford dealership. They are going to pull the engine and start to disassemble it but they say it is probably due to not getting the oil change and that Ford may not honor the warenty due to this. They say for sure the car is going to need a new engine. I realize she is 2200 miles past the oil change but that seems extreem to me that the oil change alone should cause this total lock up. Do you think this could be the lone problem or should they be looking for something else too? Also do you think 2200 miles past the oil change time is enough to void the warenty or should we fight them on that if it comes to it?
Thank you,
BILL

Answer
Hello and thanks for the question...I'll try to help.
As for the warenty goes.....I tell my customer to change the oil EVERY 3,000 miles. If they are late by 100-500 miles, fine---If they go for more than 500, I tell them to take their car to a different mechanic and not come back. I have loyal customers and I treat them as such. By going over by 2200 miles, she could of damaged her engine. An engine burns oil at the rate of about 1 qt. every 3,000 miles, give or take. Normal service indicates that she should have the oil changed at every 5,000 miles, but you won't hear that from any mechanic. They'll all say change at every 3,000 miles. With the reduced amount of oil and the thinned viscosity of the oil it is very possible that her failure to change the oil could of caused the damage to the engine.
As for dealing with Ford.......I would contact a lawyer and ask him/her.
Erik