# New Holland TC30 Hydrostatic Transmission Making Noise



## justin2988 (Jul 7, 2017)

I was pulling a trailer behind my New Holland TC30 this morning, very heavy load going thru mud, tractor was having a heck of a time with it and I pushed it too hard. Transmission started making noise and I could smell a hot/burning smell, unhooked the trailer but tractor is now making a hissing/squealing noise when I accelerate over 5 mph in forward or reverse. It still seems to have normal forward/reverse power but the hissing/squeal is very concerning. Did I burn up the transmission? Any advice?


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## sixbales (May 18, 2011)

Howdy Justin, welcome to the tractor forum.

A squealing noise might indicate air in the system. Pull the dipstick when it is squealing for a while and look for tiny bubbles entrained in the fluid on the dipstick. If so, you may have developed a leak somewhere in your suction line, probably at a connection.

If you have a suction screen, I would check it and replace the filter as well. If the fluid is not clear, it should be.....


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## RC Wells (Dec 26, 2008)

If the noise goes away once the transmission is cold, it would have been from fluid breakdown caused by too much heat. 

If the noise is gone when cold change your transmission oil and all the filters. Overheating the oil destroys the anti-foaming additives and will lead to valve cavitation if it is continued to be used even after cooling down.


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## justin2988 (Jul 7, 2017)

sixbales said:


> A squealing noise might indicate air in the system.


I think this was the answer. I read elsewhere that someone fixed their squealing noise by simply tightening their filters and eliminating the air leaks. Mine was slightly loose and I was able to get a couple of good turns on it tight. Fluid looked good and clear and smelled fine. I found the source of the burning smell to be a rubber boot that fits against the front wheel drive shaft that was loose and rubbing. Everything is fixed and greased up and the squealing noise is gone now.


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