How often do you change gear oil in PTO mowers?

[Rock Crawler]

I was just thinking, I change the engine oil/filter and grease fittings religiously. But I kind of ignore the gear oil in the PTO driven gear boxes on my rotary and finish mower. Is there a "typical" amount of years or use that you personally apply as a preventative maintenance plan for your PTO driven gear boxes? I would guess that my use is around 30-40 hours per year, and gear lube doesn't see combustion process contamination. I guess that it also does not see much by way of cooling and it sees nothing at all by way of filtration.

So please share with me your personal opinion on maintaining the gear box lube, and if you have any relevant operational experience of service related failure (lack of maintenance) I would appreciate hearing that as well.

I just wonder, if you bought a mower and ran it for a decade... or two.... would it just keep slinging grass with little to no fluid changes or is it imperative that you replace the lube more often than every year or two?

Full disclosure: I am new to the PTO driven mower scene. I am on year 2 with my "new to me" rotary rough cut mower and year one with my "new to me" finish mower. Both are likely 10-15 years old, and I have not changed gear box fluid yet, and have no clue if anyone else had ever done so.

 

[oosik]

The Operator Manual for the rotary cutter I'm looking at buying ( Rhino 300 series ) is silent on frequency of gear box oil change. Other than this - it recommends that the gear oil be replaced after the first eight hours of operation. Thereafter - ensure that the oil level is at the "check plug" level at all times. I guess it's up to the operator regarding frequency of total oil change.

 

[TerryR]

I owned my Bush Hog brand rotary mower for over 20 years. I probably used it around 30 hours a year, and never changed the gearbox oil. When I checked the level before selling it I added about a tablespoon full before it ran out the check hole.

 

[California]

I drained mine after several years and found water/oil muck, apparently from condensation. It might be worthwhile to drain it at say 5 year intervals just to see what comes out.

 

[Diggin It]

Why limit to mowers? Guess I should read up on what my Tiller manual (OK, pamphlet) says on the subject.

 

[4570Man]

How much use does the gear box on your mower get compared to your truck rear end? Most of those never get changed. Has anyone seen an rear end, manual transmission, gear box, or transfer case fail that actually had oil in it? Maybe that’s not the optimal thing to do but I think if it was a problem you’d know about it.

 

[Blue14]

I had at one time a 6FT Landpride high deck rear grooming mower and I believe I changed out the gear oil every 2 years with about 70 hours a year in the mowing season. I cannot remember if the manual even recommended changing the gear oil as I did this for my own periodic maintenance.

 

[Avenger]

Part of winter maintenance is changing the gear oil in everything. During winter maintenance, I bring in a piece of equipment, tractor, mower, ATV, lawn mower, generator, snow blower, pressure washer, etc. Doesn't matter what it is.

I log into a spread sheet that I made for keeping track of everything, and what needs to be done. Much of the info in this spread sheet is pre-populated with details I got from the owners manual, mainly maintenance schedule. But I add more things to do. This is a simply check list with notes. Its a maintenance log.

I find the spread sheet for the piece of equipment I am working on. For example the rotary mower. Not much to this one. When using daily: the PTO shaft gets lubed, blades get checked, tail wheel lubed and adjusted if necessary. Check oil level and add if low. Once a year, during winter maintenance, the entire thing gets looked over. PTO shaft gets removed and lubed, tail wheel gets lubed, blades removed and sharpened or replaced, gear box gets removed and oil changed, PTO shaft gets inspected and U-Joints replaced if necessary, cracks in the deck get welded if necessary, runners get inspected and repaired if necessary, slip clutch gets slipped and readjusted (this happens in the spring before first mowing), hitch pins gets inspected and replaced if necessary (mostly tightened), wheel bearings get inspected and replaced if necessary, and the entire thing gets washed down (in the fall before freezing temps set in). You get the idea

I note the date and work preformed on the each of the items in the spread sheet for the mower. Not exactly when I am doing the work, but when I come inside the office for a break or at the end of the day. I do this for every single piece of equipment I own.

It keeps me busy during the cold months, and keeps me in the shop working. Doing preventive maintenance is a must and keeping accurate records is just my OCD, and helps me remember what needs to be done. It can be overwhelming pulling in a tractor or whatever and breathing a heavy sigh thinking "where do I start?" Start with the maintenance log.

Do I change the oil in the gear boxes? Yep, once a year, on everything that has a gear box.

 

[Quebecguy]

I changed the gearbox oil in my Woods bush hog for the first time a couple of years ago. The bush hog was new in the late seventies and I put on about 30 hours per year. The oil was starting to look a little cloudy. When in doubt, change it - it doesn't cost very much.

 

[crashz]

I check them a couple of times a year. If they are milky with water, then I change. Or if a seal is bad. I'm mostly concerned that there is enough lube in them to do the job.