644 Highlander II transmission oil.

[Kiteman]

What type of oil does this transmission use? I don't know the transmission type. It has a JD engine. The fluid looks the same as the hydraulic fluid, but the manual seems unclear to me, like it uses motor oil 5w-20. That just doesn't seem right. Would the universal tractor trans/hyd. fluid work? Sorry for being so dumb about this, but I've had this for several years and it has finally gotten down to the add mark.

 

[joestewart]

I thought the owners manual said that it takes "C3 transmission fluid"? The transmission dipstick on my 644 also says "C3 transmission fluid". I finally found this fluid at NAPA in the 5 gallon container. Somewhere on the pail, it said that it meets C3 requirements. This topic is buried somewhere in my post of a couple of years back:

https://www.heavyequipmentforums.co...w-much-does-it-weigh&highlight=lull+644+weigh

 

[Kiteman]

Thanks, I'll read through that and check the dipstick Monday. Maybe I'll copy that page from the manual and post it here. It reads like greek to me.

 

[Kiteman]

So here's more info on my Lull's tranny. Ok, it's not Greek, it's German. There's nothing on the dipstick but the full and add marks. Hope the pics are helpful.

 

[Nige]

Try these guys. They specialize in ZF off-highway transmissions. http://www.pacifictorque.com/zf.shtml

To me those oil specifications are too tight. None of the options gives you an ambient temperature range that would cover the lowest temp you would see in winter to the highest temp you would see in summer using just one oil, which doesn't make sense.

 

[Kiteman]

Thanks to Aerolift for the info. I will be using 15-W40 diesel engine oil.

 

[joeexotic]

Does anyone know what fluid goes in the wet brakes for the lull 644 highlander? Hydraulic fluid? Mine are getting very noisy!

I thought the owners manual said that it takes "C3 transmission fluid"? The transmission dipstick on my 644 also says "C3 transmission fluid". I finally found this fluid at NAPA in the 5 gallon container. Somewhere on the pail, it said that it meets C3 requirements. This topic is buried somewhere in my post of a couple of years back:

https://www.heavyequipmentforums.co...w-much-does-it-weigh&highlight=lull+644+weigh

 

[joestewart]

Does anyone know what fluid goes in the wet brakes for the lull 644 highlander? Hydraulic fluid? Mine are getting very noisy!

JD Hy-Guard 2.4 pints, add 3 oz. friction modifier per hub. This is per page 27 of the Owner's Manual. (Note: Owner's manual is free pdf on my google site https://sites.google.com/site/deerebrown/david-brown-info-ii/other-free-pdf-manuals). For the last several years, I have been using iso46 hydraulic fluid plus the friction modifier, which you can buy in little tubes from NAPA - I think the friction modifier is the same stuff used on limited slip differentials). The hub seals on my 644 leak like crazy, so I have to constantly add fluid. Sometimes I get lazy and don't add the modifier - results in brake chatter and noise. Hope this helps.

 

[joeexotic]

JD Hy-Guard 2.4 pints, add 3 oz. friction modifier per hub. This is per page 27 of the Owner's Manual. (Note: Owner's manual is free pdf on my google site https://sites.google.com/site/deerebrown/david-brown-info-ii/other-free-pdf-manuals). For the last several years, I have been using iso46 hydraulic fluid plus the friction modifier, which you can buy in little tubes from NAPA - I think the friction modifier is the same stuff used on limited slip differentials). The hub seals on my 644 leak like crazy, so I have to constantly add fluid. Sometimes I get lazy and don't add the modifier - results in brake chatter and noise. Hope this helps.

Says cant download all pages. Would love to download that service manual you have as well. Getting so hard to find things for these older lifts.

 

[joestewart]

OK, I just downloaded the first section of the owner's manual and it worked fine for me. Can you try a different browser etc etc? If it still doesn't work for you, I'll put them on a floppy disc and send them to you through snail mail.