20w50 for Hydrogear ZT 3100s

[RhondaHonda]

It’s time to do the filters and oil in my Ferris FW35 transaxles. Locally I can get Castrol GTX or Supertech in conventional or order a 5 qt jug of high mileage Castrol GTX that is semi-syn. Valvoline makes a full synthetic VR1 oil as well but I don’t see an API rating on it. Hydro-gear calls for SL. I’ve got the filters already and am debating on which oil to use. It’ll be in there for the next 250-400 hours or so. Amsoil also makes a 20W50 motor oil or a hydrostatic trans 20W50 which I don’t think has the SL rating but should work. Opinions?

 

[wpod]

I would use a syn for no other reason than because. What do the hydros take a qt or two each?

 

[samven]

I am not an expert on these transaxles but I would be a little worried about using a modern SN rated oil over the SL they spec just because they have taken so much out of oil to meet turbo and DFI needs. I would look into a 20w50 Motorcycle oil just because its more likely to be closer to what the manufacturer originally speced.

 

[nwjones18]

I haven't done it, but had already decided on supertech for mine whenever I do get around to it.

 

[#18FAN]

I run the Amsoil in my Scag very happy with its performance

 

[tundraotto]

Hydrogear used to come stock with Castrol GTX 20W-50.

I saw a guy that sells and repairs all these hydros, and he said they all run hot and with too little oil for proper cooling, so the oil is really stressed. Also there is aluminum on steel and other cheap wear surfaces that dirty the oil pretty quickly. He stated that the best thing for preventative maintenance was to cut you mfg recommended interval in half….and not expect much more than 1000hrs of service of the ZT2800-ZT3100 transaxles. Longevity goes up from there with ZT-3400 etc but not by all that much. Conversely ZT-2200 etc and lower, the average is a couple of hundred hours.

I am going with Mobil 1 20W-50 V-Twin Motorcycle oil (API SL rating) for the high Zinc – and good tolerance to heat.

 

[bluesmokertdi]

why not use an HDEO, the additive packs are very stout

this one has 1200 ppm phosphorus

consumer products

www.mobil.eg

 

[Slick3914]

M1 15W-50 would be a solid choice as well.

 

[MParr]

I used Supertech 20W50 in my Toro. It has the ZT-3100s. It takes about 73 oz. for each side. Any 20W50 conventional will be fine.

 

[loneryder]

M1 15W-50 would be a solid choice as well.

That's what I used but I added some zinc because 15-50 is now SN rated and they took a lot of the zinc/phos out. Next change I'm going with syn 20-50 motorcycle oil.

 

[RhondaHonda]

I’d like to stick with a 20W50 since that’s what they recommend and am in the same “synthetic just because” camp. I’ll look at the Mobil 1 motorcycle oil or maybe the Amsoil hydrostatic. Any info on the zinc additive in it? The Valvoline VR1 shows added zinc (1400 ppm per the sheet) on the label but doesn’t have an API rating.

 

[tundraotto]

why not use an HDEO, the additive packs are very stout

this one has 1200 ppm phosphorus

consumer products

www.mobil.eg

It's a little too thin - hydrogear specs 50 not 40.....you will have lower power. Also diesel oils are rarely 'full synthetic' (whatever that is these days) - so in theory they have a harder time with the overheated temps in hydros.

Also forgot to mention - he does use Mobil 1 15W-50 on his rebuilds and that's what he recommends (because its economical and easy to obtain)

 

[tundraotto]

Mobil 1 15W-50 is 1200ppm phosphorous and 1300ppm zinc
Mobil 1 20W-50 V-Twin is 1600ppm phosphorous and 1750ppm zinc
normal car oils are generally under 1000ppm for both because of API limits, hence the motorcycle spec.

https://www.mobil.com/lubricants/-/media/Project/WEP/Mobil/Mobil-RoW-US-1/Files/mobil-1-racing-product-guide.pdf

 

[johnD2]

Lucas 20w-50 Synthetic motorcycle oil. That's the recommendation I got from somebody that works on them daily.

 

[The motor guy]

I ran the 15W50 mobile 1 in my gravely with the Parker pump and wheel motor setup. That was SN rated. I do believe the next oci I switched over to amsoil 20w50 which was probably SL rated, otherwise i wouldnt have bought it.

 

[ragtoplvr]

I know my hydros run so hot they scorch the grass if parked on one place. I have two hydro shaped scorched spots.. Takes a week or to to fade.

Now if parking to clean the deck, I spray down the hydro first. for about 30 seconds.

Maybe need a water tank and drip line installed for more cooling.

These are the ones that need removed to change oil.

I will pull them this winter, and use motel motorcycle oil for the refill.

Rod