Sherman hi low aux transmission

[Pooh_Bear]

I have been reading about these sherman transmissions.
I think I really like these things.

Only problem I have with getting a 9n is the 3 speed transmission.
If I got one these Sherman hi/lo aux trannys then I would have a lot more ranges to play with.

How hard are these to find.
How expensive are they.
How hard are they to install.
Are they worth it.

Thanks.

Pooh Bear

 

[Soundguy]

On ebay I see them go for 200-900$ depending on model. some are steep up only.. some step down only, and some are combo.. there is also a reverser model for forklift use, givving you extra speeds reverse. There is also a hupp pre tranny that accomplishes the same.

Thse pre trannies actually replace the tranny input shaft after the clutch. Also.. you need to check for spur or bevel cut gears, as there were differences between the 9n and 8n, Also.. keep in mind that as these change drivetrain speed.. they also effect pto speed. in other words in sherman low, and 1st gear.. your ground speed will be super low.. but your pto will be crawling too.. so it's not a good gear reducer for mowing to roto tilling. ( there are other aux trannies the change the ground speed without changing the pto speed ). Instalation involves a tractor split, and mounting it in the bell housing, and then drilling a hole via a template into the casting for the shift arm and lever. It's benefit is mostly for needed changes in travel speed. For instance.. my 2n can get up to 18-21 mph with my sherman step up tranny.

Soundguy

 

[s1120]

I have a combo in my 8N and I like it, but as soundguy says it does change the PTO speed also. Cant help withinstalation, becouse mine came with it. But If you have a chance to get one, I think you will like it.

 

[Soundguy]

www.8nford.com has an install template and some info on the shermans and other aux trannies.

Soundguy

 

[Pooh_Bear]

After test driving my 8n I think it will go slow enough to mow with.
Can't wait for the grass to start growing so I can mow with it.
Just sits in the driveway for now.
I go out every day and untarp it so I can look at it.
Love my 8n.

Pooh Bear

 

[Soundguy]

1st and second are good gears to mow in.. 1st is obviously best for higher brush.

Also.. remember.. a sherman would lower your pto speed & ground speed.. you don't want that for mowing. We all mow with our N.. 1st is fine for tall grass.. 2nd is fine for tall brush.

I fit is thick tall grass.. take a 4' bite with your 5' mower.. etc..

At pto speed.. 1st gear is 2.6 mph, 2nd is 3.4mph, 3rd is 4.5mph, and 4th is 10mph.. max speed is about 18mph at 2400 rpm.. most of us don't get over 2200 rpm.. so that is about 15.5 mph or so..

Soundguy

 

[Pooh_Bear]

I just had a thought (no comments),
Could a Sherman hi/lo be installed,
then another device installed inline with the PTO
to compensate for the slower speed of the PTO.
Does such a device exist.
Maybe something that mounts like a PTO hydro pump,
and the driveshaft mounts to that, and increases RPM.
Would be a nice project for a machinist.

What about an Everett Trencher Transmission.
How hard are these to find. How much do they go for.
How reliable are they.

Pooh Bear

 

[Soundguy]

Both the everet and howard allowed you to change ground speed without changing pto speed because they were post-aux trannies. For instance, the howard rotovator used a howard tranny. That's really the only way you got acceptable rototiller performance with a N.

They are a tad hard to find.. and when you do.. you pay for them. They are not specifically fragile.. except that many are destroyed by misuse. People mistake them for a 'low' pulling gear, which they are not. They are a low gear for ground speed only.. not a stump puller.

Soundguy

 

[Pooh_Bear]

Here is what I had in mind.
Install a Sherman Hi/Low tranny,
then add this to the pto:
http://catalogs.hubcityinc.com/farmrev/model390.html
Doesn't say what that thing would cost, but would it work.

Pooh Bear

 

[s1120]

</font><font color="blue" class="small">( Here is what I had in mind.
Install a Sherman Hi/Low tranny,
then add this to the pto:
http://catalogs.hubcityinc.com/farmrev/model390.html
Doesn't say what that thing would cost, but would it work.

Pooh Bear
)</font>

Well, It would do wat your asking if they had the right gearing. But also remember that anytime you add a gearbox, you also take HP away from the PTO. All that stepping up, and stepping down can realy eat up what little HP the old girl has. I still think if you are just mowing, you should be fine using the lower gears, if you use it for a little bit of everything, the combo trans is realy nice to have. Nice having those extra gears. I think if your still in need of a slower speed, and want to use the PTO at the same time at the higher speed, maybe a N is not the right tractor.