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Hydraulic Fluid and transmission fluid?

Bigfooteq

Well-Known Member
Joined
Jan 22, 2019
Messages
51
Location
Florida
I have am old 1979 Yale, 5k, with one-speed auto transmission. What would be the best fluid to put in the transmission and the hydraulics? Thanks!
 

TD24

Senior Member
Joined
Jan 3, 2011
Messages
295
Location
MS
Occupation
RETIRED (Mostly)
I have am old 1979 Yale, 5k, with one-speed auto transmission. What would be the best fluid to put in the transmission and the hydraulics? Thanks!
Try to get a sample. From that age. If it appears RED, add Dexron or Dexron II.
If it appears almost CLEAR with a BLUE tinge, add AW32 hydraulic oil. (Some times used Non detergent 10W engine oil)
 

Bigfooteq

Well-Known Member
Joined
Jan 22, 2019
Messages
51
Location
Florida
Thank you! It's not red. so I will use the aw32. So the hydro and trans use the same fluid correct?
 

TD24

Senior Member
Joined
Jan 3, 2011
Messages
295
Location
MS
Occupation
RETIRED (Mostly)
Thank you! It's not red. so I will use the aw32. So the hydro and trans use the same fluid correct?
Could be. Which "its: is not Red? Both?
Trans could be nearly black and a dipstick sample would smell if fluid burned
Does it have a common supply reservoir to feed both?
 

TD24

Senior Member
Joined
Jan 3, 2011
Messages
295
Location
MS
Occupation
RETIRED (Mostly)
Best I can tell it feeds both. I haven't found another fill cap or filter.
Find a Serial Number and I will try a Yale source for more accuracy. I am Clark green myself.
 

TD24

Senior Member
Joined
Jan 3, 2011
Messages
295
Location
MS
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RETIRED (Mostly)
Great, thanks!
Talked with one of my old mechanics from shop we closed in 2008. We both could recall
having worked on the particular truck, but are at loss for your specifics.
We know you use a hydraulic oil in the hydraulic system. We used AW32.

As far as we could recall, the truck has a hydraulic tank for hydraulics.
Transmission sump was its supply. Drained from a bottom plug, and added, filled, or
refilled from dipstick port or a plug close by.
We know we used Dexron in the transmissions of the ones we serviced. May be necessary
to hand/eye trace lines from hydraulic tank to determine if common.

Sorry for delay and no firm assurance. A lot of the older stuff depends on fallible
memories.
 

bunkclimber

Well-Known Member
Joined
Jul 29, 2009
Messages
116
Location
MD
I use Tractor Transmission Oil (HyTrans)from TSC..looks to be close to a AW32 for both hydraulic and transmission in my Hyster H40s..once a year oil+filter change on the transmission,been great for 15yrs now.The hydraulics for the lift are separate from the transmission but use the same oil..no issues FWIW
 
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