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

In my set up the Kaw engine gets 15/40 Delo while the tranny gets M1 15/50 . It is the winning combo for me. I use hydraulic filters on tranny and MC 910S on Kaw, Zero turn is 10 years old and going strong. I would love a new ZeroTurn but can't justify it.
 
So my gut said to try the 5W-50, but the wallet said to buy the 5 quart jug of 15W-50. Figured it was the safer bet anyway. I also grabbed 2 WIX WL10102 filters and probably did the most elaborate oil change any hydro has ever seen. See this link for the details. I'm VERY pleased with the results. The hydros are almost completely silent, even while mowing and under stress.
 
I did not know this particular oil existed. Admittedly, I'm not fluent at all in Amsoil. I would think this is the ultimate oil for this application, however, the cheapest price I see is >$12 per quart. I understand that in comparison to Hydro-Gear's kit, this is still peanuts. My real question is this:

If I choose this Amsoil product over the products I originally listed, will I *really* see enough benefit to justify the cost difference? I can get both Mobil products for $5.49 per quart at NAPA right now, and they usually have their 15W-50 on sale several times a year for well under $4 per quart.

Also, this Amsoil product claims to go double the OEM recommendation for service interval. I don't know if I'd actually trust it, so there's another reason I'm leaning toward the other offerings. It sounds like I'm convincimg myself to not buy Amsoil, but I promise I'm actually intrigued by it. Just thinking out loud. Thoughts?
The benefit in using a high quality oil in your hydrostatic transmission is offset by the cost to replace it. Check the price of replacement and then decide if a few extra $$$ is worth it. It is!
I've used the Amsoil for hydrostatic trans and it works great. I currently have the RP HPS 20W50 in mine and it works great as well. Whatever oil you choose, you want one with a good dose of zinc.
 
The current recommendation by the Hydrogear is actually "synthetic 15w50", with minimum 9 cSt @110c. In this use case, there is no combustion related contamination and cat converter to worry about, so IMO we do not need a detergent oil, and high anti-wear additive levels such as ZDDP are OK. So why not max the anti wear additives out? The M1 15w50 with its 1200 ppm Phosphorus level sounds like a pretty good choice to me.

Since the OCI is so long, I think money is probably no object, so: how do folks feel about something exotic such as an ester based RedLine 15W50 racing oil? The main disadvantage would be that these are non detergent, but in this case I think that is OK.
 
It turns out that Gravely's synthetic 15W50 ( Part #00057100) hydro fluid is actually M-1 15W50 extended synthetic.
So that is another vote for the M1 15w50. That is what I am going with. But I will put Redline in my Kawi engine. :cool:
The Gravely rebadged lubricant bottle says something about doubling the service interval. So I think the originally recommended
400 hours should be safe with the mobile.

Racing oils are typically changed out pretty fast, so they may not have enough acid neutralizers. Also, there is such thing apparently as too much zinc. Some of the redline and M-1 racing oils feature a warning about street use and long OCI-s. so given the long OCI here, those probably are
not a good choice.
 
About the Amsoil claim of doubling the service interval: It is not just them. For example. Gravely is making a similar claim on the back label of their synthetic hydro fluid. (Which is relabeled M1 15W50) . And Triax is making a 3x claim on their back label of their Hydro oil.

I think this claim is just typical difference between the "standard" dyno 20w50 which the recommended service schedule is based on,
and the "full synthetic" fluids.
 
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.
I looked up that Grasshopper 329 out of curiosity.

That’s an impressive machine.

Which engine do you have on yours?
 
Whenever I service Hydro-Gear pumps I use their filters, and synthetic 20w50 or 15w50. The last one I did was on an ExMark a few months ago, and used Hydro Gear filters and Valvoline Synthetic 20w50.
 
Mower shops carry oil supposedly optimized for hydrostatic transmissions.

The "change kit" with filter is outrageously priced.
 
Whenever I service Hydro-Gear pumps I use their filters, and synthetic 20w50 or 15w50. The last one I did was on an ExMark a few months ago, and used Hydro Gear filters and Valvoline Synthetic 20w50.
I had the ZT 2800 drives on my 2010 model CC Z-Force mower. I believe it was the first year the 2800s came out. Back then Stens sold the little spin on filters for about half of what the the CC parts counter would charge and they were the same filter. Cub recommended something like Shell Rimula 15w40 for the HG 2800 drives back then. Probably the same thing as Rotella 15w40. I too would go with a 20w50 once they get some hours on them or are used in excessive heat.

I believe the oil drains out of the 2800s when you pull the filters off, given the filters are mounted at the low point. Just make sure you can bust the fill plugs free first.
 
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I just picked up a mower with the 2800 hydros. Planning to run M1 15w-50 in them and the Kawasaki FR691 engine to keep things simple. I also have two Hydro-Gear filters ready to go on them. I figured I'm only changing once every couple of years and $20 for the filters won't break me up.
 
My ZT 3200s on my Ferris call for 20-50 in the manual that came with them. The divorced pumps and motors on my Wright stander call for M1 15-50 by name. I use M1 15-50 in both.

A filter designed for hydro service is different than a car filter, so be sure to get a filter designed for the use.
 
My ZT 3200s on my Ferris call for 20-50 in the manual that came with them. The divorced pumps and motors on my Wright stander call for M1 15-50 by name. I use M1 15-50 in both.

A filter designed for hydro service is different than a car filter, so be sure to get a filter designed for the use.
You’ve got some nice mowers.

Do you mow professionally or just have a lot of grass at your house?
 
You’ve got some nice mowers.

Do you mow professionally or just have a lot of grass at your house?
I'm just a home owner (where I use the Wright 36) and a Son-in-Law (where I use the Ferris).

My in-laws are in their mid 70s so their grass cutting production has trailed off over the years but the 13 acres of ex soybean field has remained...so I cut that with the Ferris, the suspension and suspension seat have been lifesavers. Local commercial mower dealer brought me a cheetah, a dixie chopper and a ferris to try out before I bought. They all had features I liked but the suspension sealed the deal for me. The ferris is a 2014 and has been issue free, has 200 hours on it now but they cut so fast that you really don't rack up the hours on one just being a homeowner.

I bought the Wright used, got a good deal on it because the engine was surging, ended up being an intake manifold air leak at the left cylinder head. Its a 2000 model with the fixed deck. That is ok with me because I only mow one yard with it. I put a mulch kit on the deck and use it at the main house, only half an acre but has lots of fences, gates, flower beds etc. It is a pull start Kawasaki 17HP, pretty simple machine, built like a tank, has 1700 hours on it now with no indication of any problems.
 
I used the Amsoil as well; I’ve read lots of data that essentially a good 20w50 HDEO is sufficient; I’m waiting on HPL to tell me if they’ve got (or make) their typical quality oil that can be used in the hydros.
 
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