Reply to Chris B. Weilep:
Hi
As far as I know Cat never skips Serial Numbers. Some may have a SP suffix, but that only means the machine was ordered with "Special Parts" like a faster transmission gear, (Usually 3rd ), or a different governor setting or a longer or wider U/C frame when they were options.
I don't know about the others, But the D-8Hs went into the 30,000s, (Seems to me that I've seen a Serial Number on the Richie Bros Site that was over 38,000), and I believe that the D-9Gs went into the 20,000s and that includes the side by side and in line series of Double D-9s that were made before the D-10 came out around 1977 or 78
I don't think they made a lot of D-8Ks because they had a lot of head problems because they could not get 300 HP reliably out of that block, and they were abandoned because that was about the time the High Drives took over. The D-9Hs were good Cats but the same low Serial Number run aplies for them I think. Too close to the High Drives.
Someone on here will know and reply because they have a Serial Number Book that tells you what years were in the sequence except for the end of the last year, which says "Inclusive", meaning that they were discontinued sometime that calander year.
Hope this helps
Chris
Graham - The total number is not an easy question to answer, because of the variation in model types, and the countries they were manufactured in .. meaning you have to add all the numbers produced in each model, plus those produced in each country, to reach a total ..
Sometimes there were military models, that had minor design changes, and therefore different S/N prefixes .. but these were 'slotted in' to the civilian S/No's. There were no D8H's, D8K's, D9G's or D9H's sold to the military, though, with separate military prefixes ..
Yes, Cat do number tractor production sequentially, and haven't missed any, AFAIK. Allis Chalmers, Euclid and IH have been known to skip sequential numbers.
Some early models of old Cats changed serial number prefixes, because more were produced than initially anticipated, and serial numbers were previously limited to 9999.
The D8H was produced with the S/N prefixes of 22A, 35A, 36A, 46A, 52A, and 68A .. and the D8K was produced in three S/N prefixes .. 66V, 76V and 77V ..
The D9G was produced with S/N prefixes of 66A, 90J, 91J, 29N, and 30N .. and the D9H was produced with S/N prefixes of 12U, 90V, 97V, 98V and 99V ..
Total listed production of each model, and country built ..
D8H 22A .. U.K. ............ *1514 tractors ..
D8H 35A .. U.S. ............ **776 tractors ..
D8H 36A .. U.S. ............ *5722 tractors ..
D8H 46A .. U.S. ............ 34086 tractors ..
D8H 52A .. U.K. ............ ***11 tractors ..
D8H 68A .. U.K. ............ *5901 tractors ..
TOTAL number of D8H's .. 48010 tractors ..
D8K 66V .. U.K. ............ *6328 tractors ..
D8K 76V .. U.S. ............ *1034 tractors ..
D8K 77V .. U.S. ............ 18848 tractors ..
TOTAL number of D8K's .. 26210 tractors ..
D9G 29N .. U.S. ............ ***48 tractors ..
D9G 30N .. U.S. ............ ***48 tractors ..
D9G 66A .. U.S. ............ 14593 tractors ..
D9G 90J .. U.S. ............. **114 tractors ..
D9G 91J .. U.S. ............. **114 tractors ..
TOTAL number of D9G's .. 14917 tractors ..
D9H 12U .. U.S. ............. **144 tractors ..
D9H 90V .. U.S. ............. 10173 tractors ..
D9H 97V .. U.S. ............. **194 tractors ..
D9H 98V .. U.S. ............. **194 tractors ..
D9H 99V .. U.S. ............. **144 tractors ..
TOTAL number of D9H's .. 10705 tractors ..
D9G and D9H Tractors with consecutive S/N prefixes were the Double D9's, or Side by Side D9's ..