50 hour Hydro Oil for the non believers

[CJONE]

I had the same experience as SSmoxie. My HST was a lot more responsive AND quieter after I changed oil, filter, & cleaned pre-strainer @ 50 hours. And there were wear particles & clutch wear dust in the used oil also. Significant amount of wear particles on the pre-strainer screen.

I am convinced the HST filter gets filled pretty quickly on new tractors due to this evidence in the drain pan. This means the hydraulic flow rate gets reduced substantially early, & the fluid gets hotter (more dumps over pressure relief valve). This is educated deduction, not straight opinion. Any HST I have ever owned exhibited this behavior. CJ sees it on his bike clutch packs too.

Not sure why vehicle auto trans don't seem as bothered? Maybe flow rate is lower, filter is much bigger? They are full of planetary gear set clutch packs.

btw - I like to see what everyone's experience is on this - an HST is an HST, don't care what color tractor it's on - just wanted you guys to know I don't troll :devil: - I look at interesting subjects on the daily posts & try to learn & opine. Don't care the color of your machine!

A auto trans has way less things that need to break in and looser tolerences. Brian at BTS transmissions told me not to worry about it, just run it hard, no break in needed. Most of the services I used to do were on trannys that had a problem, usually one that had been run to long and it was building varnish or overheated. Quite a few still had the plastic line plug in them so I know the pan had not been off and they were unusually clean. Just a little clutch residue in the bottom of the pan. [other than the ones that were junk anyways]. I rebuilt a couple of auto trannys and I have a lot of respect for someone that know what they are doing in some of these units. I would not do it for someone else, just myself. When Brian rebuilt my 4R100 [well no he built it] he let me watch and ask stupid questions. Very Very smart with these units, the only thing he said to do was keep the oil clean, change it often. CJ

 

[DarkBlack]

A auto trans has way less things that need to break in and looser tolerences. Brian at BTS transmissions told me not to worry about it, just run it hard, no break in needed. Most of the services I used to do were on trannys that had a problem, usually one that had been run to long and it was building varnish or overheated. Quite a few still had the plastic line plug in them so I know the pan had not been off and they were unusually clean. Just a little clutch residue in the bottom of the pan. [other than the ones that were junk anyways]. I rebuilt a couple of auto trannys and I have a lot of respect for someone that know what they are doing in some of these units. I would not do it for someone else, just myself. When Brian rebuilt my 4R100 [well no he built it] he let me watch and ask stupid questions. Very Very smart with these units, the only thing he said to do was keep the oil clean, change it often. CJ

I can't help but notice you keep throwing around the same generic description " looser/tighter tolerences" when you give your opinion of automatic automotive transmissions.
Specified tolerances are just that, and. I'm begining to think you are just lumping many other important build attributes such as TIR, clearances, materials, etc... into "tolerances".
To play devil's advocate: I would say that I highly doubt a Mahindra tractor hydro transmission is made to tighter tolerances than an automotive transmission made by Porche.

 

[murphy1244]

A auto trans has way less things that need to break in and looser tolerences. Brian at BTS transmissions told me not to worry about it, just run it hard, no break in needed. Most of the services I used to do were on trannys that had a problem, usually one that had been run to long and it was building varnish or overheated. Quite a few still had the plastic line plug in them so I know the pan had not been off and they were unusually clean. Just a little clutch residue in the bottom of the pan. [other than the ones that were junk anyways]. I rebuilt a couple of auto trannys and I have a lot of respect for someone that know what they are doing in some of these units. I would not do it for someone else, just myself. When Brian rebuilt my 4R100 [well no he built it] he let me watch and ask stupid questions. Very Very smart with these units, the only thing he said to do was keep the oil clean, change it often. CJ

Then explain why Ventac is 2000 hours before changing the fluid?

 

[CJONE]

I can't help but notice you keep throwing around the same generic description " looser/tighter tolerences" when you give your opinion of automatic automotive transmissions.
Specified tolerances are just that, and. I'm begining to think you are just lumping many other important build attributes such as TIR, clearances, materials, etc... into "tolerances".
To play devil's advocate: I would say that I highly doubt a Mahindra tractor hydro transmission is made to tighter tolerances than an automotive transmission made by Porche.

Ok I have been tolerant of your posts. I hold a masters mechanic in auto and heavy truck I think I may know a little bit about auto transmissions in cars and Allision trans in HD and medium duty trucks. I do NOT rebuild them for customers but have for myself and friends. Now as far as Hydrostats. I deal with them everyday and just got off the phone with a customer who is purchasing a stat and motor to get back to drilling. Do you know how to rebuild a rotating group? Do you know how the bores are kept to .0005 in a rotating group. Just curious. You are calling me out so I am doing the same. As far as the Mahindra stat being tighter tolerances than a Porche. I cannot honestly tell you because I don't know Porche's spec. But I will tell you when a stat gets too loose you will start overheating and loose charge pressure. These tolerances you speak of, Please inform me of Porche's specs then I can tell you where they fall regarding a hydrostat. CJ

 

[CJONE]

Then explain why Ventac is 2000 hours before changing the fluid?

Whats a Ventac? Do they share a common res with the trans and brakes? CJ

 

[murphy1244]

Whats a Ventac? Do they share a common res with the trans and brakes? CJ

Ventrac - YouTube See this.

 

[CJONE]

Ventrac - YouTube See this.

Neat little machine. With all the new units we build I recommend 4000 hour fluid change for the fist time,[we use 6000hr fluid] then depending on the fluid hour rating from there out. Now there is no gears, no friction discs [brakes] or anything to generate dirt like on our tractors. The system is extremely clean also when it is assembled. We filter the new oil as we put it in the system. We even blow cleaning plugs through the new hoses AFTER they are flushed with new cleaning solvent or diesel depending on how big the loop is. Some of these loops take almost 10 gallons of fluid just to fill them so they can be circulated and flushed. So with the Ventrac I can only assume that they use good oil,filters and it is a non dirt generating system. Hope this helps. CJ