Large Transport; Low Wing; 2 Turbojet Eng
Flight Crew Air Transport Pilot (ATP)
Confusion; Communication Breakdown
ATC Issue All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Clearance
Flight Crew Became Reoriented
Airport; Manuals
We briefed the ILS approach for 22L prior to descent into DTW.  During the descent we were given a hold clearance which we programmed into the FMC. Just prior to the hold we were then given vectors for the arrival and told to expect the ILS 22R. We briefed the first ILS approach on the Jeppesen list for 22R (ILS Y 22R) tuned the radios and proceeded in on a vector to intercept.  The controller then cleared us for the ILS Z 22R and told us to maintain 4000 ft till established with a fix that didn't appear on our map. At that moment we both recognized that the approach that we loaded wasn't what we were cleared for and then we quickly re-tuned the radios; fixed the box for the ILS Z 22R and flew the approach without incident.Our biggest concern is that there is a HUGE difference between the 'Y' and 'Z' ILS approaches to the same runway (frequency; in-bound course; decision altitude; etc.) and when selecting the first ILS for 22R in the Jeppesen application and in the FMC you will select an ILS that is potentially different than the one intended by ATC. We were dodging severe weather and may have missed the 'Z' statement from ATC (our mistake) however because of the dynamic environment we were in it was a mistake that could easily have been made.I suggest that a note be put into the 10-7 pointing out the significant differences between the ILS's to 22R (Y and Z) so that another crew won't make the same mistake.
Air carrier flight crew had briefed an ILS approach prior to their descent. During their descent they were assigned a different runway and approach. Unfortunately; they briefed the wrong approach. They discovered their error and briefed and flew the correct approach. Reporter suggests a change be made to the 10-7 chart so others don't mistake the different ILS's to the same Runway.