Hi everyone. I have an old bobcat 743 that I bought a few years back. The hydraulic fluid is low and needs to be added (due to a slow leak and changing out hydraulic fittings). I am unsure what type of fluid the previous owner used. Given that I don't know what's already in there, what would be the best type of fluid to use? Thanks. I am located inwestern Washington if it matters.
Adding hydraulic fluid to old bobcat 743
- Thread starter mousebob
- Start date
So the older machines stated that you could top them off with a good 10-30w oil but later they retracted that. A lot of people still use it though.
If you are replacing gallons of oil I would recommend a good quality hydraulic/hydrostatic oil. I live in western Oregon and used AW46 hydraulic oil in my old 742B. If you run the machine in really cold winters you may want to drop down to an AW32. You can also get multi grade hydraulic oils 32/46/64.
Bobcat brand oils are real good and are no more expensive then other good brands. They have a couple of different choices for climates now also. If it is in stock, you can order at shop.bobcat.com and if you order over $99 they will ship it to your door for free. The last time I needed oil they were out of stock.
Since when changing the hydraulic oil not all of it is replaced, the oils are always getting mixed. Every time you rent an attachment you never know what oil is in it and it mixes in with the machine oil. The best thing to do, in my opinion, is to change the oil regularly with any high quality oil that is the correct weight.
Chris 8603
Well-known member
- Joined
- Aug 4, 2023
- Messages
- 115
I used to use straight 30w in mine, not 10w30. You really don't need the multi viscosity oil in the hydro. I found mine likes the aw 64 the best. Any good hydro fluid will be just fine. Just use the best weight for your temp when it's the coldest.
