i noticed there were some D4C ag tractors with 100 HP. how did the drive train hold up with that much power in a tractor that was standard 65HP ?

Those Special Application Ag tractors used the old style sliding gear manual transmissions. Still there were issues with some bevel gear and pinions.

so were the transmission gears more robust than the 6 and 7 U tractors? same with the final drives?

I’d like to see a dyno report on the ones I see for sale. I think I saw one listed for sale once stating it was 125 hp?
My D4C is barebones stock. I think I’m leaving mine at that. Maybe it will last longer that way.
I suppose if a machine is left light enough, it would spin out rather than rip it’s internals apart like my former land leveling person with his fleet of JD2755s set up for doing narrow orchard rows.

i watched a youtube vid of a d4c pulling eight bottoms of plow. i could see it wasn't turbo charged and wasn't smoking either. could a standard d4c pull eight bottoms?

"bursitis" wrote:

i watched a youtube vid of a d4c pulling eight bottoms of plow. i could see it wasn't turbo charged and wasn't smoking either. could a standard d4c pull eight bottoms?

- there's a ton of variables when pulling a plow and plowing...soil type, shears and colter condition, depth, speed, moisture, was it pasture, on and on....
-short answer, maybe ?

"kittylover123" wrote:

- there's a ton of variables when pulling a plow and plowing...soil type, shears and colter condition, depth, speed, moisture, was it pasture, on and on....
-short answer, maybe ?

yes it was a foreign film probably german. the soil looked pretty mellow but he was plowing pretty deep. the tractor didn't labor as far as i could tell.

Guess I need to back up a bit...I was thinking D4D units. I don't think a D4C was ever designated as an Ag Unit and yes there was evolution in the D4D. Transmissions were different in the D4C (compared to "U" models) but I'd think 100+ hp would be pushing your luck.

"Old wrote:

Guess I need to back up a bit...I was thinking D4D units. I don't think a D4C was ever designated as an Ag Unit and yes there was evolution in the D4D. Transmissions were different in the D4C (compared to "U" models) but I'd think 100+ hp would be pushing your luck.

the D4c serial 40A was never an ag tractor???

Mr. Magnet how true. D4D notes as SA machines, not the C series. I’ve done my own side by side comparison, the D is a much beefier machine in contrast to the C. A lot stouter and built nicer.
Earlier 78A machines used the smaller 330 motor? My hotrod D4DSA has the way nicer 78P series 3304 with a Turbocharger. I like the close spaced gears for working. My C series, 5th is basically good for walking it from field to field.
Not to rip on a seller, but I tend to think the horses put out on most of their sales items seem a stretch.
Then again, they seem to possess more mechanical savvy than I would; many of those tractors originally came from the wheat growing regions of WA.
Maybe BP can chime in, as it seems many in his area hop theirs up.