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Mark in MD said:
Is there any entry in any manual for a mower with a peerless trans that expains specifically that these mowers should not be transported in gear?

And we all know the reverse on these mowers are "helper" reverse, not true reverse.

So is it possible the transmission is not engineered to handle "backward" stress as well as it handles forward stress?
The parts that almost 100% of the time goes bad in the tranny are called "shift keys". They slide back and forth across the main shaft via the shift collar and they have small fingers which engage the selected gear. The damage is usually cause by improper shifting. The drive belt clutch must be fully disengaged before shifting occurs or you will damage the shift keys.

Addtionally, the problem with reverse isn't a issue with the Peerless tranny, it's an issue with the lame belt drive system that most mower companies choose to use. A properly designed belt drive system will allow full reverse power. Toro T-bar mowers have a reverse and the old Gravely's with dual idlers had true reverse.
 
Photos of these broken parts from leaving in gear on a trailer would be of interest.

I would also like to understand how force is transfered through to the "shift keys" while on a trailer. It would seem to me the force would be put through the gears, not the "shift keys". What am I missing here?

Eric D
 
Eric D said:
I would also like to understand how force is transfered through to the "shift keys" while on a trailer. It would seem to me the force would be put through the gears, not the "shift keys". What am I missing here?
The shift keys slide in a slot cut into the main shaft. The fingers that I referenced above are a part of the shift key. The fingers move from gear to gear engaging that particular gear and in effect locking it to the main shaft. You are right, force is exerted on the gear that is engaged while it is also on the main shaft and the sihft keys.

These fingers that I keep referencing need a little explaining. They aren't much. They're basically little bumps that stick up above the main shift key a small amount and are a part of that key. It doesn't take much to damage them. There are slots cut into the inside of the gears that the fingers move into. Now if those gears are being driven by the engine while under load you are trying to force the fingers from one gear that is spinning at X RPM to the next gear that is spinning at Y RPM. It's that grinding as you try to force it from gear to gear that damages the fingers. You won't hear it grind but you may notice that you have to force it to shift if the clutches aren't fully disengaged.
 
www.odref.com/peerless/700-SERIES/700-757A.PDF

Look at this diagram.

Number 8 and 8A are the shift keys.

These are what actually holds your machine from rolling. NOT Good.

The wheel pullies are linked to the drive belts, linked to the jackshaft pulleys, which are coupled to the trans output shafts. When you put the machine in gear, it puts the trans gears engaged into the pinion shaft. The trans gears are sitting on the trans output shaft and linked by these shift keys. The first point of weekness would be belt tension. So under stress, the wheel pullies could slip past belt tension, causing the machine to roll.

But, if the belts and pullies are in good shape, the next point of failure would be the couplers.......which would never break in this manner. The next point is what is stopping the shaft from turning and rolling, and thats the keys.

Usually what happens is it rounds the ends over from holding the gears and rocking back and forth, eventually wearing them down which wears down the contact of the keys on the gears, which eventually causes slippage. Makes a bad grinding noise.

Also, shifting gears while moving under load can do the same. You are supposed to declutch wheel drive belts, shift, then let them back out.

I know .......who the hell does that?:rolleyes: Even i'm guilty of that one.
 
Okay. So, in conclusion...

...to prolong the life of your peerless trans, you want to always shift while the wheels are fully disengaged. Then let out the clutch gently and gradually.

And, the reason we don't want to leave the machines in gear on the trailer is because of the SUDDEN (not gradual) stress on the "weakest link" within the trans, which would be the fingers or keys as described above. This SUDDEN stress is from truck/trailer braking, pot holes, speed bumps, etc., and also from the slight rocking forward and backward that the mower does while resting in gear on the trailer.

So it's best when loading the trailer to take an extra couple seconds to put the trans in neutral, then apply the parking brake with the hand controls.

Is this a fair conclusion?

Thanks!
 
Mark in MD said:
So it's best when loading the trailer to take an extra couple seconds to put the trans in neutral, then apply the parking brake with the hand controls.

Is this a fair conclusion?
It's what I've been doing since the beginning. My 2005 Ferris gear drive didn't come with a parking brake so I modded the thumb locks and added it.
 
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