I recieved my Farmall 504 as a hand-me-down from my father last year (2007). It was the smallest and oldest tractor on his cattle farm (150 acres). The poor tractor was the red-headed step-child of the fleet.

I had to take care of some leaks on the engine, axle housings, axle seals, pto seal, quadrant leak, ect. I gutted the OEM wiring harness and started over after a meltdown. Installed a Delco 1-wire and fixed all electrical problems. I also fixed replaced nucience items like the broken precleaner and rusted cap, blown out muffler, relocated the remotes, and repaired the worn steering linkage and tie rod ends. The biggest feat was installing a new Koyker 220 front end loader with 6' bucket (AWSOME).

The only thing left was the shift quality. At least 10-12 years ago we split the tractor and replaced the main clutch and TA clutch. The TA never worked to my knowledge up to this time. We assembled it all and the main clutch (button style) was badass! Positive and no slip. The TA was lacking, actually no change... We split it again and tore into the TA. We replaced the rollers (flat) and ramps (worn). We had a machine shop knurl something in the TA, maybe the outside of the inner sprag? Anyway we put it all back together and the TA worked! The only problem, it was too aggressive.

Years later I own it and finally I had enough. When in DD if you came to a complete stop the shift lever would be in a bind. You would have to pull the TA lever into TA to relieve pressure on the shift lever. I always assumed it was due to knurling worn parts and the TA was binding. I got out the I&T manual, Farmall Operators Manual, and the Blue Ribbon Manual and studied them. I used the method in the Farmall manual to adjust the TA and Main clutch linkages to spec.

I cranked it up and I'll be a monkey's uncle, it shifted like a new tractor (almost!). All these years and the hard shifting was just poor linkage adjustment. I tried all gears in DD and TA. I could not hold the tractor in TA 1, TA 2, TA 3, or TA 4 with the brakes (properly adjusted). In TA 5, I could stall the engine out with the brakes at 1/2 throttle.

In this novel I have written, the moral is if the TA is not acting correctly or the transmission is hard to shift, sit down and read the manuals. Most likely the linkages are out of adjustment or out of time with each other (lot going on down there).

Thanks to all the seasoned IH guy out there that have put up with my relentless question asking.

Charles

Had same problem with my SMTA after reassembly, hard to shift. Someone on her mentioned adjustment so I went through it again. Made all the difference in the world in the shifting. Glad yous worked out also

Charles: This problem was actually quite well known as early as 1955. The farmalls SMTA, 300 and 400 taught us one short coming most farmers had back then. Prior to 1955, farmers had a habit of consulting the manual only, if all else failed. By the mid 1950s we were getting a whole host of equipment that required precission adjustment and the manuals became part of everyday life.

That failing YT archives have ample advice on the adjustment of TA. Close does not count, never has. TA must be adjusted by the book, no short cuts.

Hugh I mostly agree but sometimes a little country tweaking works better than factory settings. Way back when we had new high drum cotton picker that snapped a bar neck off every few days and they were $80 back in fiftys. Dealer mechanics and factory rep could not find problem but when it was taken to little cotton picker shop in Mississippi Delta for overhaul they said case was out of line squared things up added braces and problem solved.