Ford versus Deere Power Shift transmissions

It's a pretty well known fact that the Select-O-Speed transmission that Ford introduced in 1959, didn't turn out too well for the company reliability wise. Then, in 1961 they put even more HP and weight in front of it in the 6000 Commander tractor model, which was a disaster. Deere and Company came with their first Power Shift transmission in 1964 in the 4020 and then 3020 tractors and was quite successful, at least in terms of holding up. Just a couple of thoughts as to why things went the way they did. Remember, FoMoCo was using  automotive transmission parts, with drums and bands (that needed adjusting) and clutch plates, sprag clutches and the like. I'm sure many of the parts came from the cars and pickup truck transmissions they were currently building at the time. And why not ?? Try to keep things as inexpensive as possible is good business, as long as it is reliable. Deere was a completely different design, and much similar to the power shift trans Caterpillar was using in their D-6 bulldozer, with only clutches and planetaries with no drums or bands to mess with. While it was quite reliable, the power losses were somewhat of a problem, as a 4020 PS was to be able to pull 4 bottom plows like the 4010 did, even tho it was 10 more HP than the 4010. The Ford transmission was much better that way, as it's HP losses were negligible compared to a regular gear transmission.  Deere was 8 speeds F and 4 reverse. Ford was 10-speeds F and 2-reverse. Another Ford negative was gears 1 thru 4 were under 2 MPH, so it was really only a 6 or 7 speed tranny at best. The Ford tranny also coasted in half the gear selections, where the Deere did not. It took until late 1975 for Allis-Chalmers to develop and release the first power shift transmission that had drawbar HP and reliability with a total of 12-speeds to work with. It was a new and completely different design, using a countershaft in the transmission with rotating clutch packs. So, at that time, A-C had the best deal going, even tho it wasn't a "FULL" power shift transmission. It too, had some growing pains, but as time went on more PST's were sold than Power Director tractors.

Edited by DrAllis - 17 Dec 2023 at 8:30pm

I'd heard rumors that the next step was just that, but by then the Magnum all countershaft design transmission had come of age or soon to be, so it would have been obsolete without being a full power shift design. The latest 8000 series did have the 10% faster low range, which was a nice improvement over the original speed ranges.

For tillage work I am not a fan of the 10% faster low range, makes each gear that much farther apart, on a transmission that doesn't have enough speeds already. For light work its fine I guess. 

DanielW wrote: The story you always hear is: The head engineer in charge of the Ford SOS design (Harold Brock) was unhappy with the way it was produced. Ford developed the initial prototypes using some automotive transmission parts as Dr. mentioned, and also had to finesse the design to use as many of the regular tranny parts as possible. Many of the parts and subassemblies were meant to have their design finessed or beefed up before going into final production. Then the sales team at Ford wanted to be the first to produce they type of tranny, so they pressured everyone into building them asap, despite the engineering department insisting they weren't ready to go on the market yet. Harold Brock insisted they were going to be a disaster, jumped ship (most folks say he was forced out for refusing to approve the SOS design for production). He then got hired by Deere and was one of the chief engineers to work on Deere's powershift, and later the head engineer for Deere's entire tractor line. That is the way it went. Mr. Brock kept telling Ford it needed more development but they wanted to rush it to market. And he indeed did jump ship to Deere and was the man behind their Powershift. Oddly, I still want a Ford Powermaster with Select-O-Speed just for parade duty. That's the story as it's always told, anyway. I'm sure there are other facts, and the sales team at Ford would tell a much different side of the story.

the biggest problem with the select o speed on the ones that are still working now is that  dumb shift cable conection / adjuster 

And it's my understanding the IH Synchro-Tri-Six was the stepping stone to the full power shift transmission "countershaft design" for IH.  The Tri-Six was to be the standard tranny and the Power Shift was the option.  They are similar in design to a TerraGator Terra Shift or a Caterpillar 140-H transmission, both countershaft designs.

The caseIH powershift is still in production, but like the early Deere PS has been pushed to its limit on the high HP Magnum's. My brother rebuilt 8 of them this year. I believe MX315's and up. But it's a testament to the original design. 

Considering the times, how did the JI Case transmission compare? I think it was called ‘select-o-matic’

Just my 2cents- wasnt Allis doing up great with the Power Director-- not many had anything reliable,, which was an amazing design,, the deal with Allison would have been good too - but when it came time to write checks - heard Allison wanted 2  times the inital quoted price ; just things Ive seen and heard,,

“I think the late WD was the first farm tractor with a constant-mesh/helical gear transmission, which carried on into the WD-45 and then the D-17/D-19.”

Quite possibly. Oliver did not have it till the Super 55 in 1954, and next one was the 880 in 1959 or thereabouts.
Not sure when Ford started with helical gears.

tbran wrote: AC was supposed to have had a powershift for the 7000 in conjunction with Allison and depending on who you talk to - most are now gone - something didn't work out - and it left the powershift to be developed by Joe Heopfl. (pronounced help full with out the p)  Joe was the tranny engineer and struggled with getting the power shift unit into production. The only ran it in 2 - 7030-50's for testing beside the test stand. Besides loose bolts and flyball drillings and tolerances for seals and a few other issues corrected by 1978 (1976 was the first offering - called the small filter unit) the units were as dependable as one could expect. Joe struggled with gear ratios and went around the country in 1977 with E.W. (Swede) Muehlhauser getting feedback . He wanted to offer different ratios for different areas but the bean counters nixed the idea. He was not satisfied with the 1-2 shift spacing and mentioned closing up the ratios with a 3 speed rear shift but there just wasn't enough room w/o a housing change.  The size of the clutches were a hold over from the power director housings - in some cases 10 times larger than competition.  Just ramblin...

Considering the 1960-70s era, IMO the AC 7000 series Power Director's 2 speed floor buttons on-the-go shift, was an awesome feature cause it enabled the operator to "left foot" floor buttons for speed selections during headland turns while right hand levered hydraulic controls of trailing implement & right foot tapped brake to release differential lock &/or tap wheel brake to assist turn. It was an added feature over AC's prior Power Director in their D series & 100 series tractors, which was great for those series. Likewise, the AC Power Shift transmission was shooting stars ahead of anything else in the industry.

Case-O-Matic didn't go beyond the 65 HP model 830 either. That was the max HP they could make it work and stay cool under load.