Sherman conversion up to down

[QuickFarms]

Hi guys

New to the site and new owner to a 53 jubilee. Been doing a lot of research on Sherman transmissions and was wondering if you can convert a step up to step down? Is it just a gear you have to change or are they completely different? On the other hand I can find Farley cheap step ups and I do like the idea of having a faster pto speed when brush hogging. Let me know how crazy this is. Thanks

 

[TheOldHokie]

(quoted from post at 16:23:31 12/30/18) Hi guys

New to the site and new owner to a 53 jubilee. Been doing a lot of research on Sherman transmissions and was wondering if you can convert a step up to step down? Is it just a gear you have to change or are they completely different? On the other hand I can find Farley cheap step ups and I do like the idea of having a faster pto speed when brush hogging. Let me know how crazy this is. Thanks

Conversions are possible but short of making them yourself the parts to do it are unobtanium. KirkNJ has spent some time researching that possibility and will probably chime in.

TOH

 

[Den N Ms]

The case is the same on the step up and the step down.but the gears are different.Step down gears are all but impossible to find,So you just as well forget about that.The PTO higher speed with a step up is to fast and dangerous to run a brush hog safely.Things can and will fly apart!

 

[QuickFarms]

well thanks for the input. Is a step up worth installing if I can buy a cheap one. I thought a faster pto would give me the ability to throttle down he tractor. I dont need the speed just maybe the faster pto but I guess probably best to save my money.

 

[TheOldHokie]

(quoted from post at 19:41:16 12/30/18) well thanks for the input. Is a step up worth installing if I can buy a cheap one. I thought a faster pto would give me the ability to throttle down he tractor. I dont need the speed just maybe the faster pto but I guess probably best to save my money.

IMO the tractor is geared too high as is and the step up is going the wrong direction with the exception of running a belt off the PTO.

TOH

 

[John in Mich]

The Shermans are "pre" transmissions. It is in between the clutch and the tractor transmission and
becomes the input shaft for the tractor original transmission. It is changing the rpm input to your
tranmission AND the pto output speed. Step up speeds up pto rpm, step down slows down pto rpm. You can
compensate both with engine RPM. Most of the attachments that you may use require 540 rpm pto speed,
PERIOD. Therefore, step up, lower engine rpm to maintain the 540 rpm of the pto. Step down, higher
engine rpm to maintain the 540 rpm of the pto. There are charts available that describe this.
Therefore, a Sherman Combination step up/step down can do it all.
The next question becomes, "Can I run a rototiller with a Sherman"? Yes and no. Huh?
Older rotillers need the tractor to have a very slow ground speed. Standard 1st gear in a Jubilee is
still too fast for these older tillers. Remember, 540 rpm.
I have since seen a rototiller from Tractor Supply, purchased by my neighbor with a NAA tractor, work
very well. It seemed to work very well at the 540 rpm in 1st gear and, to my surprise, 2nd and 3rd
passes over the ground in 2nd gear seemed to do very well also.
I will say that the ground being worked was last year's garden. I can't say how it would do on fallow
ground with a lot of vegetation. HTH

 

[Kirk-NJ]

The sherman Brothers did make a conversion kit. I have the dealers instruction for removal and installation. Kit consisted of a lower gear cluster and the larger step
down gear. The step up and step down case was the same. Some materiel on the case had to be removed in order to get the larger gear in. Once the combo came out there
was really no reason to buy a step down conversion kit. I have looked into producing a step down conversion kit and I believe it's just not cost effective to do.
As far as picking up a step up cheap usually will mean a rebuild which will double your cost. Better to spend a bit more and get the combo. The step up will work in
your NAA but the starter bump out is different than the 8n. The step up handle is very close and will need to be altered for installation. This wouldn't be a problem
if the cable step up was used. I have found that running my finish mower in my 8n the higher range doesn't work as well in the standard 2nd gear. In my video you can
see the difference in the step up/step down gear. also have other videos shifting shermen and how to tell the difference between a shermen step up and step down in a
dead tractor, which is the best way to pick up a step down cheap (if you can find one)
sherman link

 

[Kirk-NJ]

Nancy Falk Fossum just put one in an NAA Here is the video. IMO it's a waste of time and money. Just buy a combo. Best of both worlds.
NAA sherman link

 

[QuickFarms]

Thanks Kirk. I watched your videos and they were great. You sure do know your aux trans. I would love to put a combo in just havenot seen one lately and not sure how much I can afford. I will look into the Sherman bros just to see what they offer. I just know of a step up for $250 and jut though that seemed quite cheap.

 

[Jim L WA]

Hi QuickFarms, just thought I would chime in on this. I have the Sherman combination on my '54 NAA. I very seldom use the high range. When I cut with my rotary mower, I usually use 2nd gear with the Sherman out of the picture.

 

[Kirk-NJ]

Sherman bros built the sherman trans. Long out of business.

 

[QuickFarms]

O yeah that would make sense Kirk. I feel dumb. Thanks again.