Farmall 350 vs ihc high utility350

The 350 Hi-Utility was a high-clearance version of the 350 Utility tractor which in turn was a minor update of the 300 Utility originally introduced in 1955. All of these had a wide front design, only. Guy Fay's International Harvestor Data Book, p. 194, discusses this variation on the standard utility design. A picture and article:
Link

A lot of other information and pictures of these and other IH tractors are available on Tom Harp's pages, you may want to browse around there a bit. Hope this was helpful.

Between the crank nut on front of engine to either the rubber on the ground or end of pto shaft there are only 3 power train items different between a given Farmall and Utility. 1. Reduction gears for pto. 2. Rear axle 3. Rear wheel and tire. I am excluding hydraulics and belt pullies.

I also suspect the 300 and 350 engines are a lot more closely related to each other than either are to the H.

That is precisely why we were looking at the Oliver. He had a 77 diesel in stock. My dad couldn't get very excited about the 400 Farmall diesel and gas start. Plus there was about a 1 year wait to get one.

I never did buy that tractor as I found a Farmall, which I felt could be of more use in the long run. It was as I later broke an axle. This is what I know on the subject, and never had any reason to check it further.

On the ratios to the rear wheels I suspect there is no difference as the Utilities use a higher rpm on governors and 540 pto speed. On the road in 5th gear the Utility is a bit slower than the Farmall. I know this as my neighbor had a Utility for years.

On the torque tube, are you absolutely sure what you are saying. I removed a Wagner front end loader from a Cockshutt 540 and installed it on Farmall 300 These two tractors were exactly same length from rear axle carrier to front of front bolster. A few years later I removed that loader and placed it in an auction. Before the auction started a guy came to me knowing it was my loader. He had some questions on how I did the hydraulic hookup. He advised me he had measured loader and his 300 Utility and was seeing same measurements from axle carrier to front bolster. I know he bought the loader.

I never did buy that 300U parts tractor. I found a Farmall that had burned. Was the best buy as later I broke an axle.

You can check the torque amplifier casting if you wish, I'm just going by what I was told. I wouldn't have put $0.05 in a Utility 45 years ago and I'm definately not going to spend money on any part of one now.