ZTR Mower Hydraulics Issue

Within the API service categories, phosphorus levels are mandated for SAE 10W-30 and lower viscosity grades only. Mobil1 15w-50 was reduced at some point is still fairly rich in zinc and phosphorus. However there are many kinds of anti-wear additives - and just because we see lower zinc and phosphorus, does not mean other AWs aren't making up for it.

That said, there are no catalytic converters within our mower hydraulics. Improved anti-wear performance and lower temps are going to be helpful - so I may seek out a 20w-50 (50W synthetic) racing oil instead of the off-the-shelf 15w-50. Racing oils have maximum anti-wear levels. I haven't decided between Amsoil, Royal Purple, Redline, Mobil, etc because frankly they are all excellent.

 

That is true, we were told that at school last year. At the same time exmark briggs kawaski, any many others are selling there own oil. Also we were told the profit margin was huge , sell sell sell sell sell sell

 

I think the profit on most dealer oils is huge!!! They dont own their own refineries. So its either custom blended for them or just an off the shelf oil....the latter is most likely the case.

 

Sure the margin is huge on pushing dealer brand oils. Putting hdros in a commercial Exmark is way beyond expensive. My buddy said in years he only replaced one Exmark hydro, after the oil change by Mobil 1 they did a ton of them. I'd spring for the extra $$$'s to be safe.

 

With the exmark hydro oil you can mix with mobil 1 syn and vise versa

 

I disagree. The EPA has struck. Exmark oil has zinc because it does not get burned off into the atmosphere. Mobil 1 does not.

From the article:

http://blog.horizononline.com/blog/how-to-get-more-hours-between-hydraulic-oil-changes

The Problem with Using Mobile 1 in a Hydraulic System
In the past, the standard oil for hydraulic systems was Mobile 1. A number of years ago, the EPA required Mobile 1 to take the zinc out of their oil because of environmental concerns. Mobile 1 is often used as engine oil and the EPA didn't want zinc being burned off into the atmosphere.
The problem with zinc no longer being in the oil is that it causes the oil to break down at high temperatures and you don't want the oil breaking down in your hydraulic system.
The Benefits of Using Hydro Oil

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It's a good idea to use an oil that is designed specifically for hydraulic systems. Since it's not an engine oil, Exmark has added zinc back in to their Premium Hydro Oil. This oil stays contained, doesn't burn off, and goes to a higher temperature without breaking down.
Typically if you're using Mobile 1 in your hydraulic system, you're going to change your oil about every 200 hours. If you use Exmark Hydro Oil with the zinc back in it, you're going to change it about every 500 hours. So it's actually going to work out longer and costs you less money over time.

 

Well, I just had to go and run my big mouth! Guess what?...Yup, the same hydro that I rebuilt (2008) munched the outboard axle carrier bearing tonight. I heard a loud snap from the general area of the left hydro...decided I better check things out. Got off and looked underneath, oil on the inside of the tire and the axle was obviously off center. I was able to drive to the garage normally and the left side seemed to still have good power/response and no funny noises.
After pulling the unit off and apart, no obvious damage to anything other than the outer bearing and seal. The thing that has me worried is that the oil was grey/silver. There were chunks of steel (ball bearings/cage), but all the metal flakes make me question how long the pump/motor will survive even if everything is cleaned/flushed thoroughly. This model (Hydrogear 310-2400) has only a screen on the pump, no filter.
I'll probably clean things up and throw a new bearing/seal in it. Looks like this model hydro is discontinued as far as getting a complete new unit...maybe time to upgrade mowers...I have had buyers remorse on this thing (Toro 17-52) from almost the beginning.
I'll start my own thread on this so not to clutter up dgeesaman thread.