Is there a difference between oil used for transmission lubrication and oil used for hydraulics?

I know about the different viscosities, SAE numbers, etc. What I am getting at is whether I can use the same oil in both applications. If the recommended oil for both is SAE10W-30 then can the same oil be used or do they have different properties. I'm not being lazy, I have searched the net to find this info, so I don't want links to Wiki. I'd just like to know please.Is there a difference between oil used for transmission lubrication and oil used for hydraulics?
There is a difference between the two of them to the point that you cannot use one for the other. They may call out the same name but the vicosity and the way the fluids break down are completely different. If I were you I would use the correct fluid for each item. Unless you would like a bigger problem on your hands than you have now... But if you do decide to try let me know your outcome I would like to see what the ';real'; story without the engineering sideIs there a difference between oil used for transmission lubrication and oil used for hydraulics?
The best is to get the factory specifications for your device.
For starters, transmission fluid usually has detergents added to help remove particulate matter from the gear box. Another difference is that hydraulic fluids are engineered to operate at various pressures and temperatures. The final thing is that not all hydraulic fluids are not compatible with the seals present in all hydraulic components, so if the wrong type fluid is used, it may deteriorate the seals and cause leaks.
Yes, you do need all the different oils because they have different weights and viscosity levels. You would not put 30W into a 15W motor because that would kill it.
hydraulics are a completly different animal than motor oils..
*These days they can be one in the same. Go by the detailed information in your specification pages in your manual. Tractor hydraulic (thin low viscosity) fluid is used in farm tractors to run the transmissions, hydraulic systems and the rear end final drives and planetary gears. Hows that for one type of oil. The diesel motors of coarse have entirely different oils for the crankcases. As you know in today's front wheel drive cars automatic transmission fluid circulates through the transmission and the differential ring and pinion. The same light fluid is used in standard transmissions to make them shift easier in cold climates and provide superior lubrication in hot weather.


*


A manual Transmission will use Gear oil or transmission fluid. and an automatic transmission will use Automatic transmission fluid. Gear oil is a very thick type of oil (engine oil is 30 weight and gear oil is 80 weight) that is thrown around inside the transmission when the gears are turning. Automatic transmission fluid is a Hydraulic fluid that is designed to be pumped and it operates several clutches band brakes inside the transmission. These fluids both provide cooling and lubrication to the transmission but are not interchangeable since they are very different in Viscosity and would harm the transmission if they are switched


*You can take the difference with respect to pressure , temperature and viscosity depending upon the application.


*Automatic transmission fluid is specially formulated oil 鈩?containing numerous additives to withstand grueling operating conditions. There are several different types of automatic transmission fluids and should be used according to the recommendation in your car's owner's manual.


*Automatic transmission fluid serves a multitude of purposes. Among other things, it cleans, cools, lubricates, transmits force, transmits pressure, inhibits varnish build-up and protects the transmission on a day-to-day basis.


*The overwhelming majority of transmission failures are heat-related, and automatic transmission fluid breaks down rapidly when subjected to high temperatures. Driving conditions such as trailer towing, quick stops and starts, ascending and descending mountains, and wheel-spinning in slippery conditions are but a few scenarios that can devastate the life of the transmission fluid. Although changing the fluid yourself is not difficult, it's probably best left to a qualified service technician. This is also a good time to drain the transmission fluid from the torque converter, if possible.


*The choice of hydraulic oil to be used requires careful consideration. As a generalisation, the best hydraulic oil is the thinnest that will do the work effectively as this minimises the pressure drops and pipe size/strength.





Where the hydraulic system requires the use of mineral oil, it will be necessary to allow for the change of viscosity that occurs with change of oil temperature (e.g. arctic/tropical).


*The principle task of a hydraulic oil is to transmit power; it also has to lubricate the internal components of pumps and motors within the system. Other important considerations for hydraulic systems will be the ambient temperatures over which they will be required to work and the length and diameter of pipes through which the hydraulic fluid will pass.





ISO 6743/4 鈥楥lassification of hydraulic fluids鈥?identifies no less than 15 different categories for hydraulic oils that are intended to cover every possible type of industrial hydraulic system applicable.


*Low temperature viscosity will need to be low enough to enable the system to be started without creating unacceptably high initial system pressures. At the other extreme, the hydraulic fluid鈥檚 viscosity at the highest working temperature at which it will operate will need to be high enough to provide effective lubrication of the critical moving parts within pumps and motors. Within modern commercial applications, there are a wide range of hydraulic systems which will have varying requirements in respect of hydraulic fluid performance and viscometric characteristics.





The hydraulic oils can be 鈥榤onograde oils鈥?with improved rust oxidation and antiwear properties or 鈥榤ultigrade鈥?which include the additional feature of improved viscosity index. These hydraulic fluids will either meet, or approximate to, the requirements of ISO 6743/4 Code HM or HV hydraulic fluids.





An additional requirement for high V.I. hydraulic fluids which use polymer additives to achieve enhanced V.I. is that the fluid should be shear stable.





For the more critical item of hydraulic equipment, a structured programme for sampling and onboard analysis will be appropriate. No hard and fast rules can be laid down on the required frequency of testing.
Amsoil sell a product that seems to work in 'transmissions and hydraulic equipment'. BP make something called Autran LTF which is a 'fully synthetic multifunctional fluid for automatic and power-shift transmissions. It is also suitable for automotive and industrial hydraulic and power-steering systems'. I think that is the one I will be going with ....