Do I need to replace hydraulic fluid or just filter?

[troverman]

Hi,

Just bought a 2002 L4310 GST. It has 475 hours on it, one owner. The original owner said he always did yearly engine oil / filter changes, but that the fuel filter and hydraulic fluid / filter were original. I can see that the hydraulic suction filter is original because it is still painted gray.

The question is, do I need to replace all 11 gallons of Super UDT or can I just replace the filter? Does hydraulic fluid ever go bad?

The owner gave me a new fuel filter; however, the original filter appears to be very clean in the clear bowl.

 

[Trail]

My opinion is you should do both. You're past the recommended hours for replacing the hydraulic fluid, and you don't know how hard it was worked. I know of some people that would suggest the recommended time is probably a bit early (I believe for my BX it was 350 hours) depending on its use, but given it'd used I'd say change it. Definitely do the filter.

Hopefully others with significantly more knowledgeable opinions will chime in though.

 

[Cglaza]

Even if fluid looks new or "good", you have to remember that the fluid has additives that are used up and broke down. Oil per say does not ever wear out but the additive packages put in that oil do. It is what keeps your seals in good shape and your gearing from becoming dust. Replace the fluid. Its pricey but way cheaper than a new transmission.

Sent from my SM-G900V using Tapatalk

 

[nickelplated5s]

Change the fluid and filter(s)! I got stuck with the same time/hour issue, would have negotiated differently if I knew the expense. Around here they run sales on SUDT periodically, ask around. Messicks for filters.

 

[maclean]

Do both. Use a sharpie and write the hours on the tractor and the date on the filter.

 

[troverman]

Change the fluid and filter(s)! I got stuck with the same time/hour issue, would have negotiated differently if I knew the expense. Around here they run sales on SUDT periodically, ask around. Messicks for filters.

It looks like the S-UDT will cost me about $200 for 10 gallons. I still have a gallon or so hanging around from the other tractor which should fill it completely. Filter isn't too expensive.

 

[Bulldog]

In 02 the manuals still listed a full service ,fluid and filters @50 hrs so it's way overdue. I would go back with SUDT2 which is better fluid and will give you the highest level of protection and performance. A GST tractor is not one to cut corners on. The entire trans/hyd system including the clutch pack depends on clean fluid.

A few extra dollars spent now could save you thousands in repair cost.

 

[Steve Neul]

Does that tractor have a filter or a screen? If it's a screen that is something you can just clean and put back in the tractor.

 

[troverman]

I'm going to bite the bullet and change the fluid and filter. Where could I dispose of 11 gallons of old Super UDT?

 

[MadMax31]

Auto shop. Labeled as waste oil.

When I bought my B7610, it was the same as yours, oil and filters but never touched the hydraulic. When I brought it home the first thing I did was change literally all filters and fluids. Engine oil, coolant and hydraulic. Went with UDT-2. It cost me $350 total. Seeing that I just spent 10,000 on tractor, I didnt want old fluid to ruin it.

Im at 17 hours on my BX23S, and at 50, she's getting the same treatment as my old B at 300 hours. Unfortunately, the stuff isnt cheap. But I dropped 20k on the machine, so a couple hundred bucks for a proper service is justifiable.

 

[nickelplated5s]

I'm going to bite the bullet and change the fluid and filter. Where could I dispose of 11 gallons of old Super UDT?

#1 transfer station, in the old days the dump. Around here they take 5 gallons per day for free..
#2 your neighbor with a waste oil shop heater, they will love you.
#3 any place that sells oil is supposed to accept used.