I've had my 4720h for a few months, and it now has about 45 hours on it. Two things bother me. First, there is a pronounced jerkiness in 2nd range, especially when gently pressing the go-pedals. The other issue is a loud whine from the hydrostatic transmission, especially in high range. Thoughts? Other than that, I'm pretty happy with it.
4720h jerkiness and hydro whine
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mddorange
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:welcome:
To the TBN forum. You came to the right place to get answers.
A lot of people say that using full synthetic hydro fluid will quieten down the transmission.
To the TBN forum. You came to the right place to get answers.
A lot of people say that using full synthetic hydro fluid will quieten down the transmission.
Slowpoke Slim
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Welcome to the forums.
I talked to my dealer about synthetic hydro in my tractor when it came up for service. He said he's had a couple customers that switched to synthetic and weren't happy with the switch. Seemed to make the hydro more noisy and less smooth. I think they even switched back to standard hydro. I am running synthetic engine oil in mine, but not synthetic hydro. My dealer did have to change the hydro type he put in mine at the 50 hr. The first oil he put in was too heavy for winter use up here, and was giving me problems. I'll ask him what he switched to in mine, but I've had no problems since, even running in the hot (90's) summer running my bush hog.
See if you can find out what hydro oil is in your tractor now, maybe a change to a different oil will help the issue as well?
There is an adjustment to the forward/reverse pedals, to keep them "centered". When your tractor is sitting in gear, on level ground, does it sit still, or does it creep forward or reverse? Perhaps your pedals just need a slight adjustment?
I would talk to your dealer about the issues you're having. There really shouldn't be any "jerky-ness" to your movement pedals. I'm going to assume your hydro level is correct, and you can see it in your sight glass when on level ground? It can be really hard to see through the glass, the oil is so light and clean. They do make a dye you can put in it to make it easier to see through the glass.
It did take me a few hrs run time to get used to the pedals on my tractor. They are quite touchy, both coming on, and coming off the pedal. I have to very slowly press the pedal down to get a smooth take off in 1st or 2nd range. Same with coming off the pedal, very slow and smooth, or it's like slamming on the brakes. The "pedal response" is instant.
3rd range on my hydro I only use when I transport or "road" my tractor to my neighbor's or a buddy's house a few miles away. I never use that range around my place, or to do any work on site. The gear range is just too tall for "work", just for running at road speed down the road. And yes, 3rd range definitely whines pretty good while I'm using it, but once I'm up to full road speed, on level ground, then the whine becomes very faint, almost completely drowned out by the engine.
I talked to my dealer about synthetic hydro in my tractor when it came up for service. He said he's had a couple customers that switched to synthetic and weren't happy with the switch. Seemed to make the hydro more noisy and less smooth. I think they even switched back to standard hydro. I am running synthetic engine oil in mine, but not synthetic hydro. My dealer did have to change the hydro type he put in mine at the 50 hr. The first oil he put in was too heavy for winter use up here, and was giving me problems. I'll ask him what he switched to in mine, but I've had no problems since, even running in the hot (90's) summer running my bush hog.
See if you can find out what hydro oil is in your tractor now, maybe a change to a different oil will help the issue as well?
There is an adjustment to the forward/reverse pedals, to keep them "centered". When your tractor is sitting in gear, on level ground, does it sit still, or does it creep forward or reverse? Perhaps your pedals just need a slight adjustment?
I would talk to your dealer about the issues you're having. There really shouldn't be any "jerky-ness" to your movement pedals. I'm going to assume your hydro level is correct, and you can see it in your sight glass when on level ground? It can be really hard to see through the glass, the oil is so light and clean. They do make a dye you can put in it to make it easier to see through the glass.
It did take me a few hrs run time to get used to the pedals on my tractor. They are quite touchy, both coming on, and coming off the pedal. I have to very slowly press the pedal down to get a smooth take off in 1st or 2nd range. Same with coming off the pedal, very slow and smooth, or it's like slamming on the brakes. The "pedal response" is instant.
3rd range on my hydro I only use when I transport or "road" my tractor to my neighbor's or a buddy's house a few miles away. I never use that range around my place, or to do any work on site. The gear range is just too tall for "work", just for running at road speed down the road. And yes, 3rd range definitely whines pretty good while I'm using it, but once I'm up to full road speed, on level ground, then the whine becomes very faint, almost completely drowned out by the engine.
ericm979
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Mine whines when I'm making it work hard with a small amount of HST pedal. Like when starting up a steel hill in second range or starting out on the flat in high range. My last tractor also whined more in similar situations. I don't think mine is jerky in second range but it is responsive.
My dealer said not to use SUDT.
My dealer said not to use SUDT.
The oil that's in it is what it came with new....whatever that is.
It's not the pedals I'm talking about, it's the movement of the tractor as I depress the pedal. In second range, if I press lightly on the pedal, the tractor hesitates, then lurches a bit, then then hesitates, then lurches... very annoying.
The hydraulic fluid level is correct.
In low or high range, that pause/lurch effect is not present. But there is a lot of hydro whine in high range. I don't love it but I can live with it.
ericm979
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Mine has a bit of that lurching feeling at very low speeds. I think it's the liquid in the filled tires sloshing.
I have 14hrs on my 4720CH and I also notice some surging when bush hogging very heavy brush with cruse on. Aslo, when first starting up the machine from a cold start, the pedal is hyper sensitive and mid range movement can surge at very slow speed.
FastEddieR
Bronze Member
The jerkiness in 2nd during slow speeds happens to me too. In my understanding, hat's pretty normal for a hydrostatic transmission, it can't find a low enough "gear". Try it in 3rd and you'll really feel the jerkiness. Basically it's telling you to shift down...if you need to go that slow then you should be in 1st.
The whining is loud normally but is louder after working several hours in a row, I imagine it's the heat buildup...also after several hours of work it usually creeps (forward OR backward) when I release the pedal. The only way to NOT creep when it happens is to shift into neutral or shut off and restart the engine.
The whining is loud normally but is louder after working several hours in a row, I imagine it's the heat buildup...also after several hours of work it usually creeps (forward OR backward) when I release the pedal. The only way to NOT creep when it happens is to shift into neutral or shut off and restart the engine.