The symbols you describe unfortunately meannothing to me however Imight recognise the make with photos of it.

Here is what I do know;

Glencoe did use Gresen pumps that had an integral valve assembly and they were known for short life. I always had several in the used parts area of my shop. And as a vane pump they did turn quite easily. Glencoe was a manufactuerer in IL but had no relationship to Knapheide, also an IL manufacturer. They may have been sold by the same equipment seller/installer. That is all. If the cylinders are 3.5" they are too large for your 1 ton and are likely to have far too much stroke but still works of course. The Gresen pump is about 8-12 GPM as I recall. The used pump needs to be in the same range. If it is a gear pump use this rule of thumb: 10 GPM rer inch of gear width @ 1000 RPM. Gear pumps are much more difficult to turn so don't let that bother you. Your PTO will turn it just fine unless it is a huge pump which I doubt.

Do you know the condition of the "new" used pump or could you just be replacing one worn unit with another?

Gresen vane pumps are easily rebuilt and that is what I would do. Replacing it with another brand/typw will cause installation problems that you don't need.

1953 Chevy 5-window 3100
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Dave
Engine & Driveline Moderator

If you can't make seventy by an easy road, don't go. ~~ Mark Twain