Hydrogear oil change

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Hi guys. I have a 2006 Cub Cadet RZT50, with the Hydrogear hydrostat transmissions. It has about 275 hours on it. Anyways, I pulled one of the hydros to drain the oil. I pulled the fill plug, turned it upside down, and it is draining as I type. I'm going to pick up some fresh oil for it tomorrow. My question is, I've seen recommendations anywhere from 10w-30 to 15w-40 HDEO to 20w-50 MC oil. I'm asking for your "professional" opinions on what to put back in there. It gets hot here, in the summer. Up to 105F, on occasion. I mow about 2 acres, and it takes about 1 1/2 hours. Any input would be appreciated. Thanks.

Almost forgot, when I get this one back on, I plan on doing the other side. Thanks.
 
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Please don't guess or go by "opinions". Opinions are just that, opinions. Email or call HydroGear corporate and talk to an engineer or tech services. Here is a link:

Hydrogear contact page

I've worked on TuffTorq hydrostats. Their tech told me to use 5w50 synthetic. The K46 on the JD LA series doesn't even provide for a change or have a filter. It's no wonder the average lifespan of that unit is about 250 Hrs. But that's TuffTorq, not Hydrogear.

While you are talking with them, ask if there is a filter kit that can be added to your unit. They even may be able to tell you if and/or how a drain plug can be installed. Hydrostats must have very clean oil. If those slipper feet or swash plates becomes scored, it's bye-bye hydrostat as it will self destruct quickly.
 
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jetmech has given great advice, most mower manufactures (Cub) offer "their" recommendation, but cud doesnt make it, hydrogear does, so use their recs as jetmech said.
 
Your Cub RZT50 uses 2 Hydro-Gear EZT integrated transaxles. Hydro-Gear specifically recommends 20w50 engine oil for refill of the EZTs (as Lexus114 said). They hold 52.4 ounces of oil each, a bit over a quart and a half.

Unfortunately like you found, the only way to drain/refill these is to remove, invert and drain out the top vent. You did good!

Given the PITA nature of the beast, I'd use a synthetic 20w50.

There's no external filtration options available for the EZTs. You have to bump up to the better ZT-2800 or beyond for spin-on filters.

For what ever reason on EZT equipped zero-turns, the left-hand drive tends to fail first- and early on some, like around 100-150hrs. I know some of the earlier models had issues with moisture building up in the oil and destroying the unit- so it's good to service them. Keep those drives free of debris so they can cool themselves and keep them dry if you can. You'll get good service out of them.

If you want a *.pdf copy of the service manual for these, PM me an email address and I'll sent it to you.

Joel
 
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Quote:
For what ever reason on EZT equipped zero-turns, the left-hand drive tends to fail first- and early on some, like around 100-150hrs. I know some of the earlier models had issues with moisture building up in the oil and destroying the unit- so it's good to service them. Keep those drives free of debris so they can cool themselves and keep them dry if you can. You'll get good service out of them.


+1!

Looks as if JTK has been to a few of these "rodeos". JTK, do you know if this a an MTD manufactured unit? Sounds as if it is. I was a Cub Cadet Tech in the early '70's. The IH manufactured units were nearly industructable! Even the 12 HP model hydrostats had filters and changing oil was a snap!

Man, this "planned obsolence" garbage gripes me beyond belief! Spend thousands of dollars on a machine to only get the equivelent of about 6000 to 9000 vehicle miles equivlent (100-150 hrs. x 60 mph) before a major component failure happens is inexcusiable. Others may disagree, but MTD is the Yugo of lawn equipment IMHO.
 
Yessir, MTD owns all of Cub and builds everything but some of the commercial and farm grade stuff.

The specific zero-turn mower in this thread is sold under several brand-names. Not necessarily a bad thing given today's price-point. You have to jump up to a Z-Force (or beyond) to get one unique to Cub.

You gotta remember, the old iron from decades ago sold for the equivalent of what ~$8-12K would buy today.

Joel
 
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You gotta remember, the old iron from decades ago sold for the equivalent of what ~$8-12K would buy today.


Yeah, I know, but it's still pitifull. Still, how much more would it cost per unit to add a drain plug and a spin-on filter? I'll bet it wouldn't be over $100.00-$150.00 at best. Just that alone would provide many hours of of additional service (provided the owner actually has it serviced).
 
Originally Posted By: jetmech1
..how much more would it cost per unit to add a drain plug and a spin-on filter? I'll bet it wouldn't be over $100.00-$150.00 at best.


I hear you. Unfortunately you have to bump up to a higher price-range machine to get higher-end Hydro-Gear drives that are fully serviceable w/ spin on filters.

Lots of owners have no idea what they're buying. They rarely think about the drive system on their riding mowers, which is the most important thing. More important than the engine IMO.

Joel
 
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I have a Hydro-Gear # 310-2200 EZT and was wondering if there
is enough clearance to put a thin hose down the breather tube
to vacuum out a partial amount of oil. It appears to me to be more than a notion to take each unit off. Has anyone ever heard of vacuum the unit out. Thank You.
 
gner, I've never heard of it done, but it's worth a try. It may not be a clear shot right down into the oil though.

You'd need something like a Mityvac.

Joel
 
Originally Posted By: jetmech1
Quote:
You gotta remember, the old iron from decades ago sold for the equivalent of what ~$8-12K would buy today.


Yeah, I know, but it's still pitifull. Still, how much more would it cost per unit to add a drain plug and a spin-on filter? I'll bet it wouldn't be over $100.00-$150.00 at best. Just that alone would provide many hours of of additional service (provided the owner actually has it serviced).



I`v got a fill plug and a drain plug (no filter though) what gripes me is I cant get to the fill plug.
 
Originally Posted By: lexus114

I`v got a fill plug and a drain plug (no filter though) what gripes me is I cant get to the fill plug.


That's the nice thing about some of Hydro-Gear's conventional lawn/garden tractor transaxles. Some have a means to drain/fill. Their top of the line G730 has a spin-on filter as well- although you can't see it in this pic. It's on the other side.

G730.jpg


Joel
 
Hi JTK,
I'd appreciate your advice here.
Hydro-Gear EZT drive units fitted to my Hustler - I've got just over 1000 hours up, the LHS unit is "doughy". I hve removed both units and drained them, I have refilled with fully synthetic 5W-40.
2 questions:
Do I fill the breathing chamber or leave it empty - I think it should be empty but not sure.
How do I go about bleeding the units ?
Regards,
Warren,
email: [email protected]
(I live in Australia)
 
Originally Posted By: Wazza123
Hi JTK,
I'd appreciate your advice here.
Hydro-Gear EZT drive units fitted to my Hustler - I've got just over 1000 hours up, the LHS unit is "doughy". I hve removed both units and drained them, I have refilled with fully synthetic 5W-40.
2 questions:
Do I fill the breathing chamber or leave it empty - I think it should be empty but not sure.
How do I go about bleeding the units ?
Regards,
Warren,
email: [email protected]
(I live in Australia)



Dont they call for 20W50?
 
Originally Posted By: Wazza123
Hi JTK,
I'd appreciate your advice here.
Hydro-Gear EZT drive units fitted to my Hustler - I've got just over 1000 hours up, the LHS unit is "doughy". I hve removed both units and drained them, I have refilled with fully synthetic 5W-40.
2 questions:
Do I fill the breathing chamber or leave it empty - I think it should be empty but not sure.
How do I go about bleeding the units ?
Regards,
Warren,
email: [email protected]
(I live in Australia)


Warren, you can refill through the expansion chamber(s), but be sure to not leave these little bottles full, or oil will burp out the top once they get hot. Just a small amount in the bottom of the expansion chamber is all you want when the units are cold.

5w40 is great, but for lots of hot climate usage, 20w50 would be better like suggested above, especially when the units have lots of hours on them.

Congrats on the 1000hrs on Hydrogear EZTs by the way!! I haven't heard of too many with that kind of hours. Keep them clean and dry and they do last.

Oh.. and for bleeding, all you need to do is pull the bypass rods on the drives. Start the engine and work the forward/reverse controls a few times to rid the units of air.


Joel
 
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Originally Posted By: JTK

5w40 is great, but for lots of hot climate usage, 20w50 would be better like suggested above, especially when the units have lots of hours on them.

Joel


So why is 5w40 great? But 20w50 is better? What about a climate like PA? I thought about using Mobil 1 0w40, or Shell Rotella T6 5w40 is cheaper, or stick with the Gravely recommendation and use Mobil 1 15w50.
 
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Because the Xw50 tends to hold it's properties better if these units are run hard/hot, given their small holding capacity.

If you live in cooler climates and need to use the machine in ~60F, then a 40wt variant would probably hold up just as well.
 
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