When to change hydraulic fluid in your tractor?

[WVH1977]

I have owned my tractor for 11 years. I have 450 hours on it right now. My manual calls for the transmission fluid to be changed every 300 hours. I have never changed but wondering if I should. I put a new hydraulic filter on it before winter last year but did not change the fluid. Every time I check the hydraulic fluid it looks clean and like new. I busted a hose on my grapple and had to add a little bit to it last year. The new fluid looked the same as what is in the tractor. I have heard some people say they don't change it if nothing is wrong and others that recommend changing it when the manual tells you to. I am sure this topic has come up on here before, but I am new and on here and just want some opinions on it. Should I follow the manual and change it every 300 hours or am I alright as long as the tractor runs fine and the fluid is clean with no moisture in it?

 

[DuckSlayer1017]

I'd say after 11 years you got your life out of it and it's time to change it out.

 

[2ndhalf]

I have owned my tractor for 11 years. I have 450 hours on it right now. My manual calls for the transmission fluid to be changed every 300 hours. I have never changed but wondering if I should. I put a new hydraulic filter on it before winter last year but did not change the fluid. Every time I check the hydraulic fluid it looks clean and like new. I busted a hose on my grapple and had to add a little bit to it last year. The new fluid looked the same as what is in the tractor. I have heard some people say they don't change it if nothing is wrong and others that recommend changing it when the manual tells you to. I am sure this topic has come up on here before, but I am new and on here and just want some opinions on it. Should I follow the manual and change it every 300 hours or am I alright as long as the tractor runs fine and the fluid is clean with no moisture in it?

I would change it or there will be something wrong. It is never really about the color of the oil; oil properties break down over time and use. That is why they tell you to change it not really the color.

 

[Wagtail]

Initial changing of hydraulic fluid & filter is really to flush any crap (dirt, metal filings) out of the system after a period of use. The intervals between recommended changes varies depending on the tractor... any colour & model. Some say at 50hr, some at other hr. Mine (4105) recommended at 400hr.

I did and, after that period of time, the fluid was slightly discoloured & had a few flecks in it. The filter had cleaned up the majority of 'impurities'.

Anyway, it was well worth the effort and the system works a wee bit better (at least I think so). Plus, it was a new experience to add to my 'tractor maintenance resume'.

 

[ray66v]

You probably won't get too many voting to leave it in, after 11 years.

Unlike the engine oil, my manual makes no distinction about changing it, aside from the recommended interval.

My tractor doesn't get used much anymore. And, it never gets operated in dirty conditions.

The synthetic fluid I used, has been in there for quite a few years. But, it's still far less than the recommended hours.

With under 25 hours of use each year, I may throw a filter on it at some point. But, I am considering leaving the hydraulic fluid in for the duration.

So, you won't be the only one doing it.

 

[California]

Manual transmission, or something more sensitive to contamination?

I changed mine when I bought the then-20 year old tractor (manual transmission) and the 'strainer' - just mesh - was filthy. It had the wrong o-ring securing it so at least the filter had been out before but they must not have gotten all the trash out of the system. I rinsed the transmission housing with diesel until it was clean. Then I changed the fluid again at the 30 year point and this time the strainer had minor debris in it but nowhere near plugged. I conclude for a manual transmission and hobby-CUT use maybe 10 years maximum. In harder commercial use a lot more often than this. For a hydrostatic transmission or anything with A/T-like precision valves in it, a much cleaner standard is needed so more frequent replacement. I think debris, not breakdown of any modern fluid, is the greater problem.

 

[2458n]

Change it when the water is not frozen in the oil mixture.

 

[arrow]

I think "usage" has probably more to do with it than if "when" is measured in time. I once had a tractor which I used for 28 yrs for a grand total of 1650 hrs. I changed out the hydraulic fluid 3 times with seemingly no ill effects and always used the factory stuff.

 

[topbuilder]

^ This. My compact is on a 1000 hour or every ten years, which ever comes first. Age does not break down oil.

 

[WVH1977]

I think I am going to go ahead and change it just for piece of mind. I want this tractor to last as long as possible. My next question is what hydraulic fluid to go with? New Holland Ambra multi G143 is what my manual says to use. This stuff is EXPENSIVE. Are there other brands that any of you have actually used in your tractors beside the manufacturer's recommendation? I know NAPA has hydraulic/tractor oil. I am always wondering if spending that extra money for the manufacturer's oil is a rip-off or is it really superior to cheaper hydraulic oil. It is the same way with my boat engine. I always run the oil recommended by the engine manufacturer because I am scared if I do not my engine will not run to its full potential.

Thanks in advance for advice.