Question about zero turn transaxles

[sendero]

I bought my first zero-turn mower last fall. I'm kicking myself because if I'd have any idea how superior it would be compared to my garden tractor mower, I would have done it years ago.

The mower is a Gravely ZT X 52. I love it performance. It was a year old when I bought it and the previous owner said I should take it to the local retail/service place soon and get the transaxle fluid changed.

Now I am a DIY kinda guy so I did the research, bought the filters and oil and was ready to get it done. But I could not find the fluid reservoirs or the filters. Turns out that is because it doesn't have any, it is built with "non serviceable
transaxles. They are "sealed units" as they are called. Now if I had known that is what I was getting (and apparently the previous owner didn't know either) I would have not bought this thing.

It uses the hydro-gear ZT-2200 units and to be completely factual you CAN change the fluid but you have to take them out of the mower to do so.

Now to my question. How long (running hours) can I expect to get out of these units? Apparently they are used in several low-end "residential" mowers. I don' beat this thing to death, a typical mowing session would last less than an hour.

 

[oldnslo]

Keep the dirt and debris off the cooling fins and make sure cooling fans are in good shape presuming they have fans. Doing this you should get years of service out of them.

 

[Bearsixty7]

I might be a little concerned with them.

ZT-2200 (EZT®) - Hydro-Gear

Our most popular integrated unit

www.hydro-gear.com

• NEW – Now serviceable with optional drain ports for easy oil changes

This tells me they weren't lasting as long as they planned.

 

[RjCorazza]

I agree with oldnslo's comments about keeping the fins clean and confirming the fans are in good order. Some hydraulic units are lifetime fill, like my hydraulic walk behind... Although the fluid can be drained easily enough.

I looked at an online manual, and they do state that the drive you have is basically a lifetime fill, but they do give instructions on checking / replacing the fluid. I suspect you found this manual, as it clearly states that the unit must be removed to do so. Why they didn't put a drain at the bottom is beyond me.

Is it possible that the fluid could be drained by cracking the case while installed? I'll bet someone on YouTube has some experience with replacing the fluid while installed in the machine. I think I would at least check the level, which should be easy enough.

All that said, I think I would be satisfied with checking the level, keep the cooling items cleaned and functional, and call it good!

On edit... After reading Bearsixty7's post, I think I may be a little more aggressive in changing the fluid at some point. Different animal, but my transaxle specs fluid changes at 400 hours. That may be a lifetime interval for your use. For me it's yearly.

 

[mrmikey]

I haven't got my Toro ZT out yet but I'm thinking, (scary thought I know) Don't the older ones have a raised or depressed boss where the drain port is now? I thought it was a depressed boss with a raised ring around it, I meant to look last year before I put it to bed for the winter but I forgot. Reason I was thinking about this is I noticed mine was getting lazy after it warmed up a bit and didn't seem to have the power it did when I bought it
If it does have the boss, what are the thoughts about drilling and tapping a 1/4"NPT or even 1/8" NPT hole in the case to use as a drain. Actually, it wouldn't have to be a pipe thread, it could be a standard bolt thread with a copper of fiber crush washer.

 

[ROUSTABOUT]

I haven't got my Toro ZT out yet but I'm thinking, (scary thought I know) Don't the older ones have a raised or depressed boss where the drain port is now? I thought it was a depressed boss with a raised ring around it, I meant to look last year before I put it to bed for the winter but I forgot. Reason I was thinking about this is I noticed mine was getting lazy after it warmed up a bit and didn't seem to have the power it did when I bought it
If it does have the boss, what are the thoughts about drilling and tapping a 1/4"NPT or even 1/8" NPT hole in the case to use as a drain. Actually, it wouldn't have to be a pipe thread, it could be a standard bolt thread with a copper of fiber crush washer.

The only problem with that is the aluminum case. Now, if you had a threaded boss made of steel, with threads on inside for your drain plug, and threads on outside for your case, that would work. Or, you can just put a hole in the top, get a barb fitting, and get a plastic reservoir off another mower, and plumb it to run in oil all the time. Some mowers have reservoirs on each side. It's easier to see if you have a drive problem with those. Plus, if you have to drain it, use a suction gun, or remove and turn upside down. Keep your tensioner working freely on your drive belt. Seen those get stiff, throws the belt, belt hops over pulley, ruins fans on pulleys.

 

[mrmikey]

The only problem with that is the aluminum case.

You think threading the aluminum case would be a problem? I would imagine the casting would be think enough to hold a fine thread bolt if a person didn't want to use a pipe thread. I'm also assuming there is already a fill port..that I would be leery of drilling and tapping as the crap would fall into the transmission.
You've got my curiosity piqued now, I'm going to have to dig the ole' rig out this weekend LOL.

 

[JJT]

I have no doubt the sealed tranny will outlive the air cooled engine. There are many cars with sealed transmissions running 200K+ miles.

 

[stevem5215]

Taking them out is the only option for drain and fill.
1st rule of thumb and especially on ZTR's that are going to be heavily used is to buy based on Transmission first. The heavier duty they are the better.

Now, if you are just cutting 1/2 acre lot then no problem.

 

[4570Man]

I have no doubt the sealed tranny will outlive the air cooled engine. There are many cars with sealed transmissions running 200K+ miles.

I wouldn’t take that bet. The lower end mower transmissions aren’t exactly known for their long lasting durability.

 

[mrmikey]

The lower end mower transmissions aren’t exactly known for their long lasting durability.

Yup, that's why I want to change the fluid in mine. Don't care how good a machine is, changing the fluid sure isn't going to hurt as all fluids break down eventually not to mention removing all the bits that have inevitably worn off.

 

[Yander]

I think gravely make great mowers for the money. I have had two of them one of them is still in operation with no flaws at all. My son use it to mow their grass. They Mow about two and a half acres of very rough ground.

That said, one of the transmissions was a hydrogear 3100 and the other one was a 2800.

I would sell it right now while it's a good time to sell a mower and trade up to one that at least has the 2800 transaxle.

If you're mowing a lot of grass and your budget will allow go up to the zt hd 60. That unit is considered light commercial and I can attest to its durability.

If your budget does not allow this I would follow as instructed above and keep the cooling fins clean. After about 300 hours pull them out and change the fluid.

 

[sendero]

Thanks to everyone that commented. I have done the research and yes, if you remove the transaxle from the mower you can change the fluid. There is no way around removing them. Removing them is quite a laborious task, and though I am retired and have infinite free time I'm not sure I would want to tackle that.

I have about 2 acres that I finish-mow. I tend to mow in 30-60 minute chunks as I get bored with it otherwise.

When I went to change the hydro oil I changed the engine oil first. There was quite a bit of caked on crap on the hydros. I scraped 95% of it off. At the end of the mowing season I will do it again.

I guess my strategy will be to drive it til it drops and hope for the best

 

[brokeasajoke]

As someone else posted, I buy based on engine and trans. Chances are you may be able to sell for what you have in it. I service my hydro gear units with Mobil 1 15-50.

 

[Lastkidpicked]

Though I am retired and have infinite free time I'm not sure I would want to tackle that.

I have about 2 acres that I finish-mow. I tend to mow in 30-60 minute chunks as I get bored with it otherwise.

Now to my question. How long (running hours) can I expect to get out of these units? Apparently they are used in several low-end "residential" mowers. I don' beat this thing to death, a typical mowing session would last less than an hour.

Sendero, I may have some good news for you, mathematically speaking.

Let's say your residential unit is engineered to last 1000 hours. With your good maintenance habits (I've seen your other posts and enjoy hearing what you have to say) you should get at least that out of an entry level Gravely.

And let's say you mow one hour per time, once per week, 26 weeks per year.

You will put on 26 hours per year. Let's round up to 30 because there are always reasons for a few more hours on equipment.

That means your machine should last 33 1/3 years.

You mentioned you are old enough to be retired. My sincere hope is that we will both be here in 33 years to be able to deal with those hydros at that time. . .

Or maybe our great grandkids will meet up and do it!

I'm serious about the math, and joshing with you about the rest. I hope you take it in the friendly spirit intended.

 

[Lastkidpicked]

As someone else posted, I buy based on engine and trans. Chances are you may be able to sell for what you have in it. I service my hydro gear units with Mobil 1 15-50.

And @brokeasajoke makes a good point.

If it bothers you, he is probably correct that you can sell it for what you have into it and buy a unit more serviceable.

 

[ROUSTABOUT]

You think threading the aluminum case would be a problem? I would imagine the casting would be think enough to hold a fine thread bolt if a person didn't want to use a pipe thread. I'm also assuming there is already a fill port..that I would be leery of drilling and tapping as the crap would fall into the transmission.
You've got my curiosity piqued now, I'm going to have to dig the ole' rig out this weekend LOL.

I don't think that case will handle using a bolt. I'm sure you can tap it very easy. But I've seen problems arise when removing and installing the plug. It may work a few times. I like more long term fixes myself. I've worked around them a lot. Like I said, drill the top and add a reservoir so it runs completely filled.

 

[brokeasajoke]

I don't think that case will handle using a bolt. I'm sure you can tap it very easy. But I've seen problems arise when removing and installing the plug. It may work a few times. I like more long term fixes myself. I've worked around them a lot. Like I said, drill the top and add a reservoir so it runs completely filled.

I think my 3200's have pipe plugs in them but it may have been casted thicker for it. I remember the older Eaton transaxles. My first Ferris had them.

 

[ROUSTABOUT]

I think my 3200's have pipe plugs in them but it may have been casted thicker for it. I remember the older Eaton transaxles. My first Ferris had them.

If it has a plug, it was cast for it. But if you drill a thin area and try to thread it, not so good. Really, them castings are thin, maybe 1/8" or 3/16" and that will not hold threads. He might be lucky and find an area cast for a plug that wasn't used.

 

[brokeasajoke]

Might could do one of those transmission pan drain plugs that is a plug inside the plug but that would require removing the side cover.

If it has a plug, it was cast for it. But if you drill a thin area and try to thread it, not so good. Really, them castings are thin, maybe 1/8" or 3/16" and that will not hold threads. He might be lucky and find an area cast for a plug that wasn't used.