Geared trannys-more low end torque than hydro ?

[dirtwhisperer]

</font><font color="blue" class="small">( Hyrdos are best run at higher rpms because they run off of a hydraulic pump. The motor has to run to operate the pump. )</font>

So - does this mean that a geared shuttle shift could be more durable as far as the longevity of the engine over time since it doesn't need to run near full throttle all the time like a hydro ?

 

[cowboydoc]

That would certainly be my opinion but others will not agree. The problem is there is no testing on any of this. Pretty much you just have to go by what you feel from reading everyone else's opinions. If you talk to most farmers/ranchers that do any kind of serious farming/ranching they will not have one if you gave it to them. If you talk to homeowners that have an acreage of from 1-40 they will tell you there is nothing better.

 

[slowrev]

" The higher the rpms the more power it is going to have. " Yes the more power overall, but I am talking about transmission losses not just how much power the engine is cranking out.
One thing when you stall out a gear tranny, the engine dies...well usually the tires spin first /forums/images/graemlins/smile.gif Does a Hydro act this way ? or just quit pulling and load the engine down ? If the tranny will stall out before the engine then to me it would appear that the loss can go up much higher than the manufacturer states. At least to my way of thinking. I suspect that the manufacturers % power loss in the hydro trannys is the minumim power loss and the loss is much higher at lower RPM's.

 

[BillyP]

<font color="blue"> One thing when you stall out a gear tranny, the engine dies...well usually the tires spin first Does a Hydro act this way ? or just quit pulling and load the engine down ? </font>

Slowrev, I have the JD 4610 with hydro. I've tried to stall the tractor, just for my own curiosity, but it won't stall. This was done by easing the FEL up to a tree and MFWD engaged. All it does is spin the tires.

I also tried climbing a really steep hill. Set the range to C (high) and RPM at idle and it climbed it with no problem. I did have a 616 brush cutter on the back but it was up.

 

[slowrev]

Some in here have spoken of driving into a dirtpile and stalling the drive out with hydro tranny CUT's.

 

[_RaT_]

Unless I am racing another tractor, I never use full throttle or even PTO RPM. Typical RPM is around 1900 to 2300 RPM depending on application. The same applies to my shuttles.

 

[slowrev]

Rat,
That is full throttle for larger and older tractors /forums/images/graemlins/smile.gif

 

[_RaT_]

My old International has a PTO RPM of 2200, that is not full throttle. Todays shuttles with which we are comparing the HST RPM's to are the same PTO RPM wise within a given model. Typical seems to be from 2500 RPM and up. I was recently at a train museum where with some diesels the full RPM was 450 RPM.

 

[dirtwhisperer]

here's a question - how does the manufacturer determine what sets a tractors PTO rpm - is it the peak HP rpm for the given engine ?

 

[_RaT_]

When the engine RPM turns the PTO at 540 RPM.