Farmall 400 or 450

Hi! I got Farmall 400 tractors, I just got another but it has a 281 motor in it. How can u tell 400 and 450 tractors? Are there any distinct differences in 400 or 450's? Any help would be appreciated. Thanks

Look at the sn plate....Steering wheel,white hood stripe.look at the cast codes.may or may not be the original engine.He!!,I got a friend with a late 450 that has a 248 in it.

Whatever the serial plate says it is, it is.

Lacking a serial plate, you will find that a 450 almost always has C (1957) and D (1958) date codes in the castings.

There will be holes in the top of the cowling over the hydraulic valves so that you can switch them from one-way to two-way easily.

Odds are, if the hood emblems say "400" it's just a 400 with a replacement engine. Of course, anything could've happened in the last 55 years.

Short answer, if you can only find a serial number on the ID plate. Look for the number on lever that operates the T/A clutch shaft. ITs on the left side and the rod from T/A operating handle goes to it.
Serial number 27067 or lower and the 6 digit number starts with 366, = 450 chassis.
Any serial # below forty some thousand and a lever # starting with 359 = 400 chassis.
Maybe not that short of answer.

I have a 450 that has the holes in the cowl, but what do you mean by one-way or two way? I have not used remote cylinders on it, just pulling an old-fashioned Servis stalk-cutter, so I don't know much about their hydraulics. Thanks.

The late 400s had a C-281 in them.

The late 400s had a c-281 in them.

you can set a 450 hydraulics for one way or two way operation at the valve.

Serial number is 15611,.. Nothing else is readable on the tag. Does that mean it a 450?

Look close at the lever that the t/a handle moves when shifted on the side of clutch housing.
See if a part # can be read. If its 359507R1 thats a 400 chassis. If its 366352R1 its a 450 chassis. The serial number you posted could be for a 400 or 450. I just mentioned the serial number break in case IH stuck the 450 lever in some of the last few 400 tractors. They would have a over 40,000 serial # though. way above what the 450 tractors went to.
400 tractors also have a clutch pedal travel stop bolt in the very bottom of the pedal. It has a square head with a jam nut. 450 tractors didn't use the bolt.
Lots of other things to look for but none are fool proof after the years since made. 450 used a all plastic covered steering wheel that went on a splined shaft. 400 was keyed and just covered on the outer ring. 450 used a key switch below the instrument panel. 400 in the panel.
To ID the engine look for a serial number on a raised flat place in the block casting just above the sheet metal cover on the oil filter side of the block. If no number can be found it may be a replacement block. If is has a serial it may tell what tractor it started in. Guess you found C-281 on the block. Look forwar on the block from it to find a date code. Raised cast numbers and letter. Like 4-8-C. Thats the month and day casting was made with the letter representing a year. Depending on numbers and letter you have can tell when the block was made.