Hydro Additives

[rmaynard 15,459]

Has anyone tried this stuff in an older Sunstrand transmission?

 

 

Just curious if it helps give new life to old hydros?

Edited July 23, 2021 by rmaynard

[953 nut 55,229]

                I tend to doubt it will do any good in a Sundstrand, there are no clutches like you find in an automotive transmission.

[daveoman1966 3,751]

The ONLY way to get new life to the older hydros...rebuild them.  For the Piston-to-piston units, rebuild Hyd Pump and Hyd Motor.  For the even older Sundrans Hydrogear units, a refurb is mostly limited to the Hyd Pump. I have posted .pdf files...with pics...to aide in the overhaul of these.  

 

[rmaynard 15,459]

12 minutes ago, daveoman1966 said:

The ONLY way to get new life to the older hydros...rebuild them.  For the Piston-to-piston units, rebuild Hyd Pump and Hyd Motor.  For the even older Sundrans Hydrogear units, a refurb is mostly limited to the Hyd Pump. I have posted .pdf files...with pics...to aide in the overhaul of these.  

 

I have a 1965 875. Ran great when I got it 2 years ago. It was running Type-A fluid. I drained it, put on a new WH filter, and filled it with Wolf's Head fully synthetic multi-purpose fluid since Type-A was not available. Really slows down going up hills. So yesterday I did filter and fluid change again, but used Castrol High Mileage older transmission oil (Dexron). Maybe a little bit better. Wish I could find Type-A.

So if I decide to rebuild, what's the availability of parts?

The reason I changed the fluid in the first place was because the P.O. never knew where the drain plug was and only topped it off.

Edited July 22, 2021 by rmaynard

[squonk 41,118]

I highly doubt Type A if you could find it would help at all. Dexron has everything Type A had plus other additives for the changes that occurred with clutch and seal compositions.

[pfrederi 17,739]

13 hours ago, rmaynard said:

I have a 1965 875. Ran great when I got it 2 years ago. It was running Type-A fluid. I drained it, put on a new WH filter, and filled it with Wolf's Head fully synthetic multi-purpose fluid since Type-A was not available. Really slows down going up hills. So yesterday I did filter and fluid change again, but used Castrol High Mileage older transmission oil (Dexron). Maybe a little bit better. Wish I could find Type-A.

So if I decide to rebuild, what's the availability of parts?

The reason I changed the fluid in the first place was because the P.O. never knew where the drain plug was and only topped it off.

 

 

When you went from Oil to ATF did you completely drain and flush the system??  oil and ATF do not play well with each other.

If your valve plate is deeply gouged  i think LJ fluid power has them but $$.  If your slippers are beyond help you have to get a whole new piston block and slippers.  about 10 years ago I was quoted $5-600.

If it works reasonably well now then you should be able to get away with resurfacing the valve plate and slippers

[rmaynard 15,459]

@pfrederi the tranny has never had motor oil in it. Only Type-A fluid, Wolf's Head synthetic (red ATF fluid), and now the Castrol ATF (Dexron).

Edited July 23, 2021 by rmaynard

[pfrederi 17,739]

14 minutes ago, rmaynard said:

@pfrederi the tranny has never had motor oil in it. Only Type-A fluid, Wolf's Head synthetic (red ATF fluid), and now the Castrol ATF (Dexron).

  Sorry misread you post thought Wolf's head was oil.  Anyway,  i run DexMerc In all 6 hydro gears no problems with any of them.  Slowing down going up hills going faster down signs of old age.  Good news is you probably only need a resurfacing.  Even before that you might try the Hydrogear Tune up  (about the only hydro gear repair WH mentioned.)

 

 

[rmaynard 15,459]

Thanks. I'll look into that.