Used the wrong oil in Hydro Gear ZT3100 Transaxles!

[madams135]

I own a 52 inch Husqvarna ZTR with Hydro Gear ZT3100 Transaxles. I decided I needed to change the transaxle oil and filters as I never have in my 4 years of ownership, and I don't know if the the prior owner had ever changed.

As I was filling the second transaxle, I noticed I had grabbed the wrong jug of oil. Oops! I had used the oil for my car, 0w-20 Valvoline extended protection full synthetic. I was supposed to use the 15w-50 Mobil 1 full synthetic.

The oil I drained looked milky, dark, and used up. I put 50 hrs a season on the mower in upstate NY. Could I get away with using the 0w-20? Even if only for a season or two? Surely it is better than what was in there? I really don't want to do this all over again and waste $25 of oil, but I also don't want to damage the equipment. Any insight would be appreciated!

 

[dnewton3]

I would say change it, mainly so that both units have the same vis for a good "feel" and response curve, due to the viscosity/temp differences.
I doubt any real damage would occur, but it's not going to behave the same, side-to-side.

 

[NibbanaBanana]

That sounds like a big difference. 15w-40 or 10w-50 or 10w40? Probably okay. But you're talking 5 degrees of overlap there. I would bite the bullet. Drain it and filter through a fine paint strainer. Use a little bit in oil changes. Maybe a pint. Use for general lube oil can oil.

 

[#18FAN]

Oil is cheap Hydro units are not change it out…
You may get away with pulling and reusing the filters.

 

[madams135]

I would say change it, mainly so that both units have the same vis for a good "feel" and response curve, due to the viscosity/temp differences.
I doubt any real damage would occur, but it's not going to behave the same, side-to-side.

Good point. I should have mentioned that I noticed during the second fill, so atleast each has the same oil.

 

[scoot]

I use Valvoline 20w50 synthetic in my hydros , change every 80 hours . I have 500 hours now . Runs like a champ .

 

[JTK]

Have you run the machine with the 0w20 in the ZT3100's? Once you got them purged, are they quiet and putting out full power?

They'll probably be OK on 0w20 for now if so, but I know I wouldn't be able to live with it. I'd throw a new pair of filters on and refill with a good 15w40 or 20w50

 

[madams135]

Have you run the machine with the 0w20 in the ZT3100's? Once you got them purged, are they quiet and putting out full power?

They'll probably be OK on 0w20 for now if so, but I know I wouldn't be able to live with it. I'd throw a new pair of filters on and refill with a good 15w40 or 20w50

I did the purge quick on a lift, then turned the mower off. I didn't do a test run. I was in a hurry and rushed for time, which clearly is the reason I made the mistake in the first place.

 

[loneryder]

Change it back to 15-50. Hydrogrears are too expensive to mess around with. The new 15-50s have less zinc than they used too. I added some zinc to the last time I used 15-50. I’ve now switched to Amsoil hydro trans fluid so I don’t have worry about it.

 

[SubieRubyRoo]

The lower number is less relevant because nobody is going to run their mowers below 0F. HydroGear uses 20w50, probably so there are a minimum of VIIs to shear; the 50 grade is spec’d because hydro pumps heat the oil a whole lot. I’d bet in use that the oil is easily 250F. Get that 20 grade out right away.

If you’re on a budget, a 15w50 or 20w50 from WalMart will work; you can obviously also use any of the upper tier oils like Amsoil, Redline, HPL. Dave @High Performance Lubricants actually made a bespoke line of lubricants for our hydros; I ordered it in 20w50; another member got it in 5w50. It’s got a super high HT/HS to protect your hydros, but really if you’re willing to change it more often. I ran the Amsoil Hydro oil for 100 hours and it came out absolutely clean and brand new; I will likely run the HPL for at least 200 hours before even sampling it.

Long story short, that 20 grade has no chance of protecting your pump under heavy use & high temps. Drain it asap, then be sure to purge the hydros well after filling & before use.

 

[Hall]

I really don't want to do this all over again and waste $25 of oil, but I also don't want to damage the equipment.

How much are new hydros, $500, $700, or more EACH ? Can you install them yourself or will you need to pay a shop ? You're worried about $25....

 

[loneryder]

The lower number is less relevant because nobody is going to run their mowers below 0F. HydroGear uses 20w50, probably so there are a minimum of VIIs to shear; the 50 grade is spec’d because hydro pumps heat the oil a whole lot. I’d bet in use that the oil is easily 250F. Get that 20 grade out right away.

If you’re on a budget, a 15w50 or 20w50 from WalMart will work; you can obviously also use any of the upper tier oils like Amsoil, Redline, HPL. Dave @High Performance Lubricants actually made a bespoke line of lubricants for our hydros; I ordered it in 20w50; another member got it in 5w50. It’s got a super high HT/HS to protect your hydros, but really if you’re willing to change it more often. I ran the Amsoil Hydro oil for 100 hours and it came out absolutely clean and brand new; I will likely run the HPL for at least 200 hours before even sampling it.

Long story short, that 20 grade has no chance of protecting your pump under heavy use & high temps. Drain it asap, then be sure to purge the hydros well after filling & before use.

I would pull the filters and at least drain them as well as you can.

 

[brillo54]

Another vote to change it. By their function, hydro's are buried underneath, don't get great air flow around them and can be covered with dirt and grass. They typically run hot and depending on your yard size, may run for a few hours straight. Unless your unit is very lightly used, I'd get an xxW-50 oil back in there.

 

[madams135]

Thanks all. You are all right, not worth it for headaches down the road. Any good ways to strain and save the removed 0w-20? I think I saw a fine paint filter recommended

 

[scoot]

Thanks all. You are all right, not worth it for headaches down the road. Any good ways to strain and save the removed 0w-20? I think I saw a fine paint filter recommended

Ugh

 

[Fordiesel69]

The small hydro gears run rediculously hot. There is no large mass to delay the temps. I put 5w20 in my Eaton 1100's in my Toro so the attachments can lift in the cold. The tranny case is a huge block of cast iron and it takes 2 hours to get it to 150f to 200f.

But with hydro gears there is not mass they are gunna get real hot and thin the 20weight out.

 

[Hall]

Any good ways to strain and save the removed 0w-20?

You're talking about $6-8 dollars, yeah ? Drive to the store to buy this paint filter that might work, use gas and your time, and you think it's worth it ?

 

[Fattylocks]

Thanks all. You are all right, not worth it for headaches down the road. Any good ways to strain and save the removed 0w-20? I think I saw a fine paint filter recommended

Why would you even have to strain it. Shouldn't be coming out chunky.

 

[SubieRubyRoo]

How much are new hydros, $500, $700, or more EACH ? Can you install them yourself or will you need to pay a shop ? You're worried about $25....

They’re more than that. And you have to disassemble half the mower to get them out. $25 doesn’t even cover the cost of a new filter if you’re using the Wix 10112(?) as those are about $33 each now. Dump the 20 grade including the filter, stick the filter that had 20 grade in it back on, fill with a 50 grade of your choice, purge well, and get to mowing!

 

[martinq]

Thanks all. You are all right, not worth it for headaches down the road. Any good ways to strain and save the removed 0w-20? I think I saw a fine paint filter recommended

I'd put it through a coffee filter and reuse it. I would dilute it down to 20-50% with new, fresh oil of the same type.