2014 GM Class V Hitch

I can't see why a reducer would lower the trucks hitch rating The same forces are being applied to the hitch whether the reducer is there or not. In other words the hitch doesn't know... WHat will reduce is the rating for the 2" shank assembly compared to a 2.5" shank.

My 2012 GMC also has a 2.5" hitch/reducer and there is nothing in the literature I have found saying hitch capabilities are reduced when using 2" shank/reducer.

If however, I was approaching those kinds of weights then I would probably spring for 2.5" shank/hitch assembly

I noticed that when i was buying my truck, GM does not de-rate it if using the reducer, like some others do.

The reducer means that everything attached to the receiver is going to be 2" and not 2.5" and so it will not be as strong. Why would anyone expect a 2" ball mount couple as strong as a 2.5" one?

The 2" steel ball mounts are rated for 7500 lbs. while the 2.5" ones are rated for 18,000 to 20,000 lbs. which is not that surprising. Why make a ball mount that that is twice as strong as the receiver in which it will be used? The Class IV receivers are rated for load of 10,000 lbs. maximum so no reason to have a ball mount rated for twice that amount.

My truck's factory receiver is rated for up to 13,000 lbs. so its capacity would be greatly reduced with a 2" ball mount that is rated for only 7500 lbs.

So it sounds like its not the sleeve thats limiting the capacity, its the 2" shank itself which is limited by its own constraints. In other words you cant tow a 15,000 lb trailer using a 2" shank and ball. If you are going to tow those weights you need a 2.5" shank. If however you are using a 2" shank to tow 7000 lbs and the shank its rated to handle the wieght you should be fine using the sleeve.