I am once again seeking advice from the elders, this time on a troy-bilt horse tiller. I have read countless topics on this and other forums about how troy-bilt originally recommended gl-1 90 or 140 weight gear oil in the tillers. Well since I live in the south and summer temps are typically in the 90's and 100's, plus factor in the leaking tine seals I need to replace, I have decided on the 140 weight gear oil. Only problem is, unless I want to order a 5 gallon bucket of the stuff, my only option is gl-4 gear oil. Is the gl-4 any risk to the gears in the tiller? I have read the gl-4 has a lot less additives than gl-5...but gl-1 is non existent in my area. I am not too familiar with gear oils, so not sure what is ok to use. I know most gl-5 bottles say "yellow metal safe", but again not very sure if that includes the older equipment. Also, would adding Lucas oil stabilizer to the gear oil be ok? In the summer heat, the tine seals behind to vent/seep the gear oil over time since a tiller being a tiller tends to sit up most of the year unused. I'd like to drain out the old gear oil but not until I know I have the correct replacement on hand. I would rather not use multi-viscosity due to it being mostly liquid like at room temperature, which would not help the seeping problem while sitting up most of the year. Thanks for the help fellas!!!!!
need opinions on tiller gear oil
- Thread starter mech_tech
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you can substitute motor oil for gl-1
I doubt you find a good gl-4 rated 140wt gear oil... and it has too many additives anyway.
20w50 engine oil should be similar to 90wt gl-1 gear oil. IIRC
other option that I feel might hurt your gears
http://www.napaonline.com/Catalog/Catalo...4238_0006410049
I doubt you find a good gl-4 rated 140wt gear oil... and it has too many additives anyway.
20w50 engine oil should be similar to 90wt gl-1 gear oil. IIRC
other option that I feel might hurt your gears
http://www.napaonline.com/Catalog/Catalo...4238_0006410049
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I really advise to replace those seals. It is not difficult, just takes patience. Then you can run Mobil Super Syn and be set for life.
Would the synthetic be better suited for the long storage times associated with tillers? I would LOVE to run a synthetic gear oil, but no where have I read anything about how the synthetic acts with brass/bronze metals. I know the gear oil currently in there is quite thick like syrup and is dark brown in color. I didn't get any water out of the bottom drain plug, but I'm sure in the last 35 years the gear oil has absorbed/mixed with dirt or moisture at some point in it's life. I just want to put in something that will protect it from the long storage times between use.
Propflux01
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I got my GL-1 140w at NAPA for my antique tiller. Was about $7 for the quart. Replace the seals. Not hard to do but will stop the leaks.
When I needed to fill the case on my Ariens snow blower. I went with MTL because it was safe for brass. People told me it was too thin. Grease is better. All I can say is that after being worked hard for an hour or two, the case was cool to the touch.
Troybilts have a good reputation, but a used one leaks. The seals are in churning dirt and don't last. The shafts wear down as well. Checking the lube should be done before use. Expect to top it off. I would use 140 only because thicker isn't available.
Troybilts have a good reputation, but a used one leaks. The seals are in churning dirt and don't last. The shafts wear down as well. Checking the lube should be done before use. Expect to top it off. I would use 140 only because thicker isn't available.
I assume the gears are hypoid gears (the way the gears are cut) and so you should be using a hypoid gear oil. The "yellow metal safe" refers to whether it reacts with bronze gears.
What does Troy-Built say? I would not worry about north or south as people in the north are normally tilling gardens in warm weather not the winter.
What does Troy-Built say? I would not worry about north or south as people in the north are normally tilling gardens in warm weather not the winter.
Use 140 weight oil, any brand will do. Many of the troy-bilt guys on the small engine forums say that GL-5 is fine because the gears are not under enough pressure and not spinning at high enough speeds for it to cause damage.
Ok, after calling just about everyone in the area, I have found a one gallon jug of 140 gl-4 gear oil at o'reilly auto and a 5 gallon bucket at napa of 140 gl-4. Even called the local bulk plant and they could not get it in gl-1. Is there a synthetic gear oil that is yellow metal safe and thick like 140??? I noticed the gear oil flows about the same as lucas oil stabilizer, which says on the bottle it can be used up to 100% in gear cases. Would using lucas oil stabilizer be a mistake? I know I am being picky, but the last thing I want to do is put in something that is worse than the old oil still in there. This tiller doesn't see much use so I want to use something that will protect it during the long storage times, hints the reason for my determined search.
Originally Posted By: andyd
I would use 140 only because thicker isn't available.
Wait one second, would anyone here trust STP Treatment? You know, thicken the oil and stop the leak!!!
I would use 140 only because thicker isn't available.
Wait one second, would anyone here trust STP Treatment? You know, thicken the oil and stop the leak!!!
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I got my qt of Sta-Lube API/GL-4 SAE 140 at NAPA. The Sta-Lube part # is SL24228. Sta-Lube technical service # is 1-800-521-3168 and customer service # is 1-800-272-8963. Your NAPA counter guy should be able to order the qt from they're whse. I've ran the Sta-Lube in my old tiller for years with never a problem.
Well, I am happy to say I finally have a 5 gallon bucket of 140 gl-1 gear oil!!!!!!! I was able to find one Napa that had it in stock, but they outsource it since they do not keep in in their warehouse. I was also able to find two other local companies that could order it. Prices once said and done always ended up under $60, and no one could get anything smaller than 5 gallons at a time. I almost went with the O'reilly gallon jug of gl-4, but after finding a website with actual pictures of copper corrosion tests done with gl-5 oils, I refused to use anything other than gl-1 in the tiller. The friendliest guy I spoke with was at Warren oil, and he also seemed the most knowledgeable on this oil. He told me it's the sulfer in the gear oil that eats away at the yellow metals. From what I have found online, the worst yellow metal gear oil was the Lucas synthetic, which in the pictures actually turned the copper black after only 3 hours of the heat test. I had no idea gear oil could be that corrosive. Most bulk plants in my area couldn't even order the stuff, nor had anything in the book to cross it over to. If anyone has any questions on finding this oil, PM me and I can give you specifics on where I found what. Hope this information helps someone out, cause this has been a long search for me!!!!!!
What about a heavy motor oil. HD40 or 50, maybe a 20w50. Or the above mixed with STP or something similar.
Harvey
Harvey
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