Hydraulic fluid type for a Deere 690C, any help is appreciated! Thanks!

[gravinus]

Hello Everyone,

I'm buying a really nice low hours 690C for working around my property, don't expect I'll be racking up a ton of hours on it.

I'm planning to change all the filters/fluids to be on the safe side and start fresh with it. I've been reading some conflicting posts on the best route to go with the hydraulic fluid. I was going to take a sample and have it analyzed, but at the end of the day, I guess I can't be sure exactly what type of fluid is in it now.

First question- Should I be running a 303 hydraulic fluid or motor oil? The spec sheet calls out 303, but I think Deere advised owners with the 690E to swap to motor oil in the system. I guess the Linde pumps used on the 690E's were prone to failure because the JD hydraulic fuel wasn't good at absorbing water that would get into the system.

Second question- If I send in a sample and the fluid comes back in good shape, can fluids be mixed or would I need to drain the complete system (80 gallons) and start fresh. Thats a big expense I'd like to avoid, but I really can't afford to blow a pump out either, if there is a chance it could be avoided.

Any feedback or suggestions would be greatly appreciated!!!
Ben

 

[td15c]

jd trans.pdf here is the hydro oil spec for the 690c.the 690c has gear pumps and gear pump drive motors so its not real picky. when I had one I ran mobil 424 transdrolic in it, same as deere hygard. The hydraulics on a 690e are completely different than a 690c

 

[gravinus]

Hey TD15c!

Big thanks for the reply and taking the time to post the specs, much appreciated!! Thats great news that this baby isn't quite so particular, I can sacrifice the performance for ease of maintenance. This is only my 2nd digger, the last being a 1956 American 395BC dragline, so I'd imagine this will already be space aged for me! That old American worked pretty well once you got the hang of it, but I was always convinced I was going to die in that thing, safety really didn't exist back then!

Thanks again!
Ben

 

[Delmer]

303 is such an old spec that I wouldn't use it in anything with a number other than 8 or 9 in the model. Fine for H's, B's 8n's etc.

$40 a bucket is not bad for hydraulic fluid, $20 is just too cheap, there's junk in there that you don't want in your machine, unless you know it's already grossly contaminated. $40 is the sale price for hydraulic transmission fluid at FF, F&F is similar.

 

[td15c]

303 does not meet deere hygard spec. 303 Tractor Hydraulic Fluid has not been recommended by any OEM for model years later than 1974. when I said 690c was not picky I did not mean you didn't have to meet spec there are lots of quality name brand oils out there. if your going to use a tractor hydraulic oil it needs to meet deere hygard spec.

 

[gravinus]

Hey Guys,
I get what you were saying TD15c, per the document you sent me and for my temperature range of used, I need an oil that meets J20A specs at a minimum. From what I've read and to Delmers point, it sounds like the rock bottom fluids may meet that spec, but contain other contaminates and won't absorb the moisture all that well. I'll get my system tested and if the oil is still decent, I'll top her off with some Mobil 424 as you suggested.

Thanks guys!!
Ben