Hydro-Gear ZT-2800s - What oil & what filter?

#1: Did you read the service manual?
#2: There are many professional landscapers @LawnSite.com using the Mobil 1 15W50, with good results.
#3: Dealing with hydrostatic transaxles and not engines.
#1: Yes, but admittedly I have a lot on my plate so it was slightly distracted. FWIW, I've also read Kawasaki's engine manual many times and I don't follow their outdated/substandard recommendations either.
#2: I know any of the above would be acceptable or even great, but remember what forum we're on...I want the best.
#3: I understand this, but the FR series engines from my experience seem to love 5W-30 synthetic. Kawasaki told me it may not even stop short of blowing it up. I always do my own research and draw my own conclusions.

Not criticizing your input at all. I'm open to all input and opinions. Just learning.
 
#1: Yes, but admittedly I have a lot on my plate so it was slightly distracted. FWIW, I've also read Kawasaki's engine manual many times and I don't follow their outdated/substandard recommendations either.
#2: I know any of the above would be acceptable or even great, but remember what forum we're on...I want the best.
#3: I understand this, but the FR series engines from my experience seem to love 5W-30 synthetic. Kawasaki told me it may not even stop short of blowing it up. I always do my own research and draw my own conclusions.

Not criticizing your input at all. I'm open to all input and opinions. Just learning.
Wait! Hold up just a minute!
Hasn’t this thread been about the correct oil and filters for the Hydro-Gear ZT-2800s?
If that’s the case, 15W50 Synthetic or any 20W50 is what you need. For filters, you can pick those up at NAPA or any outdoor power dealership.
For engine oil, SAE 40 HD, 15W40, 15W50 or 20W50 is fine. Kawasaki recently updated their oil specifications to allow for 20W50. Kawasaki has stated that possible oil consumption can occur using 10W40. Those choices are up to you. I don’t have a Kawasaki engine on my ZTR. If I did, I would use any 15W40 HDEO that was on special.
 
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#1: Yes, but admittedly I have a lot on my plate so it was slightly distracted. FWIW, I've also read Kawasaki's engine manual many times and I don't follow their outdated/substandard recommendations either.
#2: I know any of the above would be acceptable or even great, but remember what forum we're on...I want the best.
#3: I understand this, but the FR series engines from my experience seem to love 5W-30 synthetic. Kawasaki told me it may not even stop short of blowing it up. I always do my own research and draw my own conclusions.

Not criticizing your input at all. I'm open to all input and opinions. Just learning.
Actually, I would have tried using Mobil 5w50, but decided to use Mobil 1 15w50, because the 5w50 wasn't available. My reason was same as yours, thinner at cold temperature. I too have a Kawasaki FR engine and now running 5w40HDEO. I have used 5w30 PCMO, but not noticing a difference.
 
Take a look at Rock Auto...

Pick your oil, and add the Wix filter....


 
Wait! Hold up just a minute!
Hasn’t this thread been about the correct oil and filters for the Hydro-Gear ZT-2800s?
If that’s the case, 15W50 Synthetic or any 20W50 is what you need. For filters, you can pick those up at NAPA or any outdoor power dealership.
For engine oil, SAE 40 HD, 15W40, 15W50 or 20W50 is fine. Kawasaki recently updated their oil specifications to allow for 20W50. Kawasaki has stated that possible oil consumption can occur using 10W40. Those choices are up to you. I don’t have a Kawasaki engine on my ZTR. If I did, I would use any 15W40 HDEO that was on special.
(I'm seeking peak protection/performance first, cheap and available second)
I guess the key question here is which is better, a 5W-50, a Euro 5W-50, or a 15W-50, and technically & specifically why? WHY does a hydro like 15 over 5, or vice versa?

For engine oil, the Kawasaki manual calls for 10W-30 or 10W-40, or monograde for both. XW-50 does not exist. I personally have run synthetic SN rated 5W-30 for years and never had an issue. Even when it's 100°. It even lists 10W-30 physically on the oil dipstick. But I have to discredit their recommendations a bit, because Iit has never used ANY oil when using the synthetic 5W-30. Not once, not even a little. So the "will" warning is somewhat laughable.

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Just bought a new-to-me zero turn with ZT-2800s. It's 6 years old and only has 230 hours on it. Hydro oil reservoir is a little dark, so I'm changing it out of caution. I've never serviced hydros before, but I'm not stupid. Based on my research through countless threads here, Hydro-Gear's website, and the internet abroad I've drawn my initial assumptions.

Oil:
I feel these hydros need a XW-50. It seems they're specified for a 50 that's SJ rated. I plan to use a full synthetic oil regardless of recommendations. My top 3 picks (not in order) after some research (I'm seeking peak protection/performance first, cheap and available second) are:
Mobil 1 15W-50
Mobil 1 FS X2 5W-50 (European)
NAPA 15W-50

If you think I'm overlooking a good candidate, please chime in.

Filter:
I have no idea at all! I need some help. The only thing I know to do is go to my mower brand dealer and ask for two filters. I'm hoping for an easy cross reference to a WIX or NAPA Gold product, but if the dealer filters are best, then that's what I'll do. Regardless, if it's not a truly perfect cross reference, I don't want it. Saving a few dollars and rolling the dice is not worth replacing 2 hydros. Ever.

Any input is appreciated.
They require an SJ oil which has more zinc than the new SN oils. Those oils you listed have less zinc in them.
 
15W50 M1 or 20W50 M1 motorcycle oil Change per recommendation. 5W for below freezing operation.
 
They require an SJ oil which has more zinc than the new SN oils. Those oils you listed have less zinc in them.
The higher zinc was my assumption as well, until Hydro-Gear themselves blatantly dismissed this theory. Their own "genuine" oil is SN rated.

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I guess the key question here is which is better, a 5W-50, a Euro 5W-50, or a 15W-50, and technically & specifically why? WHY does a hydro like 15 over 5, or vice versa?

For engine oil, the Kawasaki manual calls for 10W-30 or 10W-40, or monograde for both. XW-50 does not exist. I personally have run synthetic SN rated 5W-30 for years and never had an issue. Even when it's 100°. It even lists 10W-30 physically on the oil dipstick. But I have to discredit their recommendations a bit, because Iit has never used ANY oil when using the synthetic 5W-30. Not once, not even a little. So the "will" warning is somewhat laughable.

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To answer your question, lets take a look at what Hydro-Gear's service manual says. No one put it here so I guess I will.
The fluids used in Hydro-Gear products have
been carefully selected, and only equivalent, or
better products should be substituted.
Typically, an engine oil with a minimum rating
of 9.0 cSt (55 SUS) at 230° F (110° C) and an
API classification of SL is recommended. A
20W50 engine oil has been selected for use
by the factory and is recommended for normal
operating procedures.

The key point here is:
Typically, an engine oil with a minimum rating
of 9.0 cSt (55 SUS) at 230° F (110° C) and an
API classification of SL is recommended.
-First of off, don't bother trying to find a API SL. The latest API are backwards compatible and using a 40 weight oil and higher are not subject to the ZDDP limitation. The min. of 9.0 cSt at 230 F(110 C) is the key. Looking at oil specification sheets, you will learn that the oil is rated at 100 C, so you will need to plug in a formula to figure the viscosity out at 110 C. I have done that all ready and learned about all your 40 and 50 weight oils will pass that. Because of that, I don't see that you will have a problem using a 5w50. Go ahead and use 5w50 and tell how it went for you. Wouldn't mind hearing how it goes. I know TuffTorq is recommending 5w50 in there's now. Why 15w50 gets used is because it is the closest to 20w50 that is relatively available in synthetic. You can get a synthetic 20w50 but cost more than a 15w50.
 
My Scag has the ZT2800 transaxle. It has about 150 hours now and I've changed the gear oil twice already. Each time it seems to be much more responsive with fresh oil. I used Castrol 20W-50 the first change and Supertech 20W-50 the next. The first filter swap I used Hydro-Gear filters but this time I used the Stens 120-738. Mine used all of a 5 quart jug with new filters. If your mower is anything like mine it is best to do the change in hot weather because I had to pour the fresh oil in through the overflow tank and it drains sloooooooow into the transaxle if the temps are low.
 
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My Scag has the ZT2800 transaxle. It has about 150 hours now and I've changed the gear oil twice already. Each time it seems to be much more responsive with fresh oil. I used Castrol 20W-50 the first change and Supertech 20W-50 the next. The first filter swap I used Hydro-Gear filters but this time I used the Stens 120-738. Mine used all of a 5 quart jug with new filters. If your mower is anything like mine it is best to do the change in hot weather because I had to pour the fresh oil in through the overflow tank and it drains sloooooooow into the transaxle if the temps are low.
I used Super Tech 20W50 for the first change and WIX filters. I have the ZT3100s on my Toro. You are correct about the hydros being more responsive after a change. Yes, buy 5 quarts. I have about 180 hours on mine and I will change again in about 100 more hours. Purge the system as directed and adjust the tracking if needed. I’ve gotten mine to track straight as an arrow.
 
My Grasshopper 329 zero turn uses hydro gear G2 pumps and parker wheel motors my fluid change interval is every 1000 hrs and the only choice i have in fluid is Grasshopper cool temp hydro max and it cost $210 for 2 gallons or about 26 per quart.
Mine has a little over 400 hrs and the fluid is still nice and amber.
 
My Scag has the ZT2800 transaxle. It has about 150 hours now and I've changed the gear oil twice already. Each time it seems to be much more responsive with fresh oil. I used Castrol 20W-50 the first change and Supertech 20W-50 the next. The first filter swap I used Hydro-Gear filters but this time I used the Stens 120-738. Mine used all of a 5 quart jug with new filters. If your mower is anything like mine it is best to do the change in hot weather because I had to pour the fresh oil in through the overflow tank and it drains sloooooooow into the transaxle if the temps are low.
Or use a 15w50 or 5w50 if the weather is not hot.
 
Or use a 15w50 or 5w50 if the weather is not hot.
I did the hydro oil change back before the weather warmed up here in Florida (in the 40's) and the 20W-50 flowed like syrup but when I use the mower in the Florida summertime heat it is just what I need. I also use straight 40W in the Kawasaki engine as it is recommended for the hot summer temps here in Florida.
 
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