# Auger Gear Box Oil Question



## TheCaptain

I have read conflicting information regarding newer GL-5 rated gear oils and their potential corrosive effect on the "yellow metals" such as what I understand are brass gears and linkage in the auger gear box of my Toro 421 2-Stage.

There isn't a lot in the gear box per the specs, 89ml (3oz). I can say it has never been changed in the 34 yr life of this machine. The manual states to drain and refill at the end of every season with SAE 90 EP Transmission oil.

It has proven difficult to find a straight SAE 90 EP trans oil, considered to be a GL-1 from what I've read. The local TS has a 5L bottle of what appears to be SAE90EP for old Ford tractors. That's a LOT of oil though relatively speaking 5L at $18 isn't a bad deal. My only other locally available options would be a GL-5 rated SAE 80W-90 in the range of the manual specs. Those run about $9 a bottle after tax.

What do you guys run?

Thanks!
-Kirk


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## UNDERTAKER

use the 80-90 w gear oil. do not use the synthetic stuff the seals will not hold the syn stuff. MAHALO!!!!!!!!!!


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## detdrbuzzard

using the 80w90 oil is acceptable according to toro


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## mkd

don't be suprised if there isn't much oil in your gearbox after 34 yrs or when you add the new oil it just doesn't run right out. on my 28 yr old ariens i used grease instead of oil and it stayed in place. the grease is what john deere recommends for their combine corn heads because it is so sticky. not saying that's what you should use but it kept my old ariens working several years right up to the day i sold it. John Deere Special-Purpose Corn Head Gun Grease - AN102562


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## detdrbuzzard

mkd said:


> don't be suprised if there isn't much oil in your gearbox after 34 yrs or when you add the new oil it just doesn't run right out. on my 28 yr old ariens i used grease instead of oil and it stayed in place. the grease is what john deere recommends for their combine corn heads because it is so sticky. not saying that's what you should use but it kept my old ariens working several years right up to the day i sold it. John Deere Special-Purpose Corn Head Gun Grease - AN102562


 some toro's used oil and others grease, mine call for grease and will be checked and refilled this spring


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## TheCaptain

Thanks guys. I think I'll wait till winter is done before doing anything. That way if I do have leaking after the change with 80W-90 I'll look at either grease or rebuilding the gear box as part of my planned full tear down and paint project over the summer.


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## brickcity

how often are you supposed to change the oil or grease?
your manual says every year? i have a five year old machine and i only checked it for level last year. i figured if it wasn't leaking i'll never change it but i'm pretty ignorant when it comes to such matters.


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## UNDERTAKER

just keep the oil toped off. when the time comes for new seals. take it apart clean it up put the seals in. and oil it up. MAHALO!!!!!


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## brickcity

thank you.
this really is a great website for information


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## Toro-8-2-4

Some Toro auger gear boxes call for a light weight EP 00 grease. It stays fluid in very cold weather. It is thinner than the typical EP 2 grease but thick enough to not run out worn shaft seals. Stens and Oregon sell it. If you google on 00 grease you will easily find it.

I see this as something in between 90w gear oil and the typical EP 2 grease found in most auto parts stores. Also, I have used Mobile 1 grease in a MTD auger gear box and it seems to be fine so far. it is rated to -40 degrees.

I think you have the right approach. Use some kind of grease until you have the time to replace the seals if need be.


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## Toyboy

I use Marine lower unit grease in mine and change it every two years. I have it all the time for my outboards and your only talking about a cup or so, not a big deal.


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## Sid

*The gear oil*

My 66 sears/murray called for 30 wt oil in the gearbox. after some years I opened the gearbox, and changed the auger shaft, and the seals, all three, and I started using 70/90 synthetic gear oil, and everything is fine, no leaks, and no detectable ware. So far so good [25 years on the rebuild].
Sid


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## Kiss4aFrog

The hard part is what was good 25 years ago and recorded as the correct fluid to use can in many situations be replace with something better. IMHO I'd go with the SYN70/90 over engine oil any day. One benefit is it's less likely to leak out of an older gearbox if you haven't done the seals yet and it will protect the gears better.


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