Hydraulic Fluid Maintenance (Fan/Steering)

[Dave Atherton]

Fred, made reply to hydraulic fluid maintance but landed over in the jack section.
Dave Atherton

[Edward Buker]

Glad to hear that someone has gone to Transynd without issue. Thanks for that info Bill. That will certainly last longer then Dexron but it leaves you with the dilemma when if ever should you change it again.

Fred, I agree an ounce of prevention is worth a pound of cure always. That being said I do not want to throw money down the drain by changing fluid that is in excellent condition. I know after 20 years, which seems a bit crazy I admit, but the fluid looked just like new fluid every time I changed the filter. I would go to change the filter with the intent of changing the fluid and just take a pass until next time given it looked perfect. I also was in that Dexron 1, 2,3, 4 etc dilemma. I never replaced any component in that system. So forgetting the change interval how concerned should I be at 90K miles?

I did some calculations and estimated that in 90K miles I had about 2000 operating hours on the pump and system. I went and did a search and pulled up a PDF on a mini Cat hydraulic excavator with a small backhoe which has to be working harder with more heat generated for the fluid then our hydraulics. Cat call for a hydraulic fluid change at 2000 hours/2 years for standard fluid and 3000hrs/18 months for Hydro Advanced or 6000 hours/3 years with SOS analysis unless you are using a hydraulic driven hammer attachment. I think the interval in years is driven by the possibility of condensation being introduced.

I find Cat to be pretty conservative in general with maintenance intervals. They generate the service intervals based on fluid analysis. Without a contaminant issue or condensation issue this fluid probably has a useful life of 100K miles or more would be a reasonable estimate. This is one of those fluids where oil analysis would really help.

Later Ed

[LaMonte Monnell]

Where is the hyd filter located.....2001 Contessa......on the pump itself?

[Edward Buker]

LaMonte,

Not sure on yours, on mine there is a hydraulic reservoir in the service bay (most rear passenger side compartment) with a white spin on cartridge filter (looks like a 1 quart size) mounted in front of the tank. Look near your hydraulic reservoir or in this service bay where fuel filters are.

Later Ed

[LaMonte Monnell]

thanks so much Ed!

[Doug Allman]

Mike Groves. We have a 2004 Marquis C-12 and I asked Gerald about the filter for the previous non long life coolant. He indicated that the filter lines were one of the most critical items to get removed. They are not the quality needed and as a result were the cause of many breakdowns and worse.

I follow Geralds advise very closely. I went about removing the filter base and the rubber lines. I had to remove the alternator and staring me right in the face was a crack 1/2 way around the rubber line at the filter connection. Did not look wet however.

As I went about the removal I did however find that the line(s) were actually leaking. Just forward and on top of the chassis rail it was wet.

From my vantage point and Geralds input I do not see how you could ever do any inspection and see if there was a problem with the lines or the filter mount. Everything in the area of the filter mount and for at least 16 inches forward is impossible to review in total.

I had been having to add antifreeze after every trip. Most of the time a quart or so, but I never could see where it was leaking from. Was not on the floor and not in the oil.

I guarantee you you do not want to have to do a fix for this piggyback coolant system that you do not need when you are on the road. It is not a 15 minute fix. 4 hours and a lot of tools plus antifreeze containers along with two plugs of different size and a lot of grease and fluid up your arms. Do it while it is your shop and drive along with no fear when the temp guage rises a little.  (It takes 9 gallons of antifreeze that you are not going to get along side the highway)