Transmission Whine
 

My Model 70 has a whine in the transmission when it is in gear. I haven't used it much since the whine started.

Any ideas on what it could be? It doesn't make any noise in neutral. I have a creeper and have checked fluid levels, which check out fine.

I'm no mechanic, but... does it whine when the creeper is in low range also or just in high range? Does it whine in all gears? Is the whine louder in one particular gear or is it about the same in all gears?

What transmission fluid are you using and how old is it ??

:bigthink:

Another question to consider....Is the whine in the transmission or is it in the creepy gear or is it in the driveline or clutch?

Cub Cadet 123

I have newer hytrans in the rear end as well as the creeper. Doesn't matter if it is in high or low on the creeper. It also doesn't matter what gear the tractor is in.

The fluid is at the proper level and not low.

It only whines when the tractor is moving. If it is out of gear with the shaft spinning, it does not whine.

It sounds like its in the transaxle.

I was told it may be the bearings in the countershaft.

I don't think it's one of the counter shaft bearing, the counter shaft speed changes with the gear selected and then so would the whine. If it does it in both low and high range I don't think it's the creeper gear. So now we're left with the main shaft bearing, the reduction gear bearings, and the redudtion gears themselves. If it's none of those the only other thing I can think of is the clutch release bearing.

usually when you get a whine like that its ring and pinion setup

Ok. So I assume to figure it out, I'll have to tear into the transaxle. Will any of these theories have something obvious to check while its apart?

Here are a few photo's of what to look for, some of these are extremely worn, but I hope it gets the point across. These are just examples

What in the world pitted those gear teeth? Rust?

I'd surely replace the bearings, but given that we're dealing with a garden tractor not a land speed record vehicle, I'd use that ring/pinion set and not give it a 2nd thought.

It looks as though those teeth wore through the case harding rather
than rust.
I've seen it before over the years.

Just curious, how you're making out?

Straight cut gears whine.

Haven't torn into this yet. Been busy with other stuff. I know it's never made this whining sound before, and I've driven this thing since I was 9 years old.

Uhmmm, wouldn't the 70 have spec'd gear oil for the tranny and creeper???? The whine may not be anything but gear noise from straight cut gears. Running the lighter (much lighter) HyTran will make any gear or bearing noise worse, but not necessarily hurt anything.
Only solution may be to go to the correct oil or add a oil conditioner like something from Lucas to thicken it up.

(My Kubota M4500 spec's 80 wt for the tranny and hydraulics. Kubota now says use UDT/Super UDT which is essentially same as HyTran. Talk about noisy! But, doesn't seem to hurt it, never any filings in filter.)

I refilled it with HyTran about 12 years ago and dutifully check the fluid levels. Mine calls for either 30 weight engine oil or HyTran. Maybe I'll change the fluid completely and look for any metal in the fluid before I tear into this thing.

Well, I haven't changed the fluid yet, but did a little experiment with it. If I push it around in neutral, it does not whine. Does that help narrow it down? I thought maybe it would eliminate the ring and pinion gear since it would be moving.

:bigthink: how did you not turn the ring and pinion ? What you eliminated was gears in trans...

Sounds like a bad bearing to me.

The ring and pinion will react differently with actual torque from engine and trans than just pushing in neutral. You are not applying any load in neutral.

I agree. Sounds like a bearing

Don't wast yer time/ $$ on an oil change or adding snake oil, it will not change anything.
It is very possible that moisture over the years has pitted a bearing or several and that is what you are hearing.
it would be a good winter project in the off season.

Sounds like I'll be tearing into this after fall when the leaves are finished. I'll post updates when I tear into it.

Thanks for the comments.

I'm just impressed anyone can hear transmission whine over the general racket of a Kohler power Cub! :-)