Here's some quick information: TractorData.com Ford 82 tractor information
The Ford "800" is a series of tractors, so your Grandpa's tractor will be an 8xx (as in the above example 820). The site that I've linked to will have the information once you've looked and determined. Also, the serial number of the tractor will help to determine what year it was built.
Welcome.
Model & Serial number location on the left (sitting on the tractor) on the flat spot above the two holes, behind the starter. Posting a photo would also help.
RK 55HC,ym1700, NH7610S, Ford 8N, 2N, NAA, 660, 850 x2, 541, 950, 941D, 951, 2000, 3000, 4000, 4600, 5000, 740, IH 'C' 'H', CUB, John Deere 'B', allis 'G', case VAC
yep.. post pictures, the more the better.
It's very common to have parts swapped and replaced on these old tractors. tin and even the transmission. We can look at your tranny serial number and model ID, then look at the rest of the tractor and see if they match. Either way, we can tell you what you have.