I'm going to stick my big nose in again. The 4.11 rear was actually an option on overdrive cars and standard on non-od cars, so it will surely pull that gear and then some. The second point is that you have the early (Hudson-built) rear end there and it will be OK if not abused but it's not something you want to spend much money on. The differential gears (not the ring and pinion) are way too delicate for the Hornet engine. They will stand up better behind a stickshift than a Hydramatic but they are not strong. Don't ask me how I know Sometime in '52 they changed the entire rear end and the later ones are very durable so you should look for one. The ratios are the same and 4.10 is probably most common. It is a straight bolt in as I recall. I changed one on the parking lot of my apartment building with a small set of Craftsman tools. That was when I was about 25 and had just learned about how easy it was to bust the rear. It was a particularly strong running Hornet with some hot rod parts and my Dad told me that if I kept driving it the way I did the rear end would fail. I didn't listen ... I have a lot of seat time in stepdown Hudsons and I can say that a Hornet will easily cruise at 70-75. It is turning up some rpm and feels like it needs another gear but it will. The last one I had did many long trips with my heavy foot on it and didn't even use any oil (although it sure did like gas) but your engine is pretty worn so I can't recommend that at all. I'm just sayin. If I ever get another one it will definitely have an modern automatic with overdrive. That would be a huge improvement. I love your car and I love the fact that you are going just drive it the way it is, even more.