Ford dealer sheared two bolts

That depends entirely on the shop and how and why the bolts broke off. In my area bolt breakage is very common due to rust. Nothing I can really do other than use the tricks I have learned over the years to get them out. If they still break off then I am very used to drilling bolts/studs out and replacing them. I charge for the time involved to do that.

In this case it would be hard to say as shops all have different practices. You might be able to make the case for them to pay for the repair if you called Ford customer service (corporate, not the local dealer, number should be in the owners manual or online for your region) and spoke to them.

Many thanks for your prompt response. The thing that troubles me most is fact that they failed to remove sheared off bolts with extraction tool, as I said to them there is a knack to doing this I.e. using dot punch to center drill entry they said that they have lots of sheared off bolts and very little success at drilling them out. Was quite willing to pay the £170 quoted but now feel miffed at the fact that they failed on what I have found a reasonably simple task when I have had to perform it in the past on rusted sheared bolts on satellite dishes.

Yep, there are definitely a few tricks about them. My SOP is to use as much heat as possible then give the head or nut a couple good raps with a hammer. Then some more heat and a candle pressed near the threads so it can wick into the threads. Then hit it with an impact on lower power and see if it moves. I will say I am impressed with a couple of the battery powered units for this, they hit faster so the bolt does not have time to flex as much. If they still break off it is grind it smooth, center punch and use a left hand drill bit. Equal parts praying and cursing seems to help.