4x10s are noisy and have lots of engine vibration.

[yellowsocks93]

I dont get how your 990 runs worse when warmed up. Mine runs a little louder when first started then when I mow for 3 hours and idle it's quiter. Our 970 surges when it first starts up so you have to give it a little more throttle until it warms up then it is fine. I guess my tractors have the old 70 series motor while you have the new and improved TN motor.

 

[BGL990]

I didn't mean it runs worse. It definitely doesn't. Just somewhat louder with more of the typical diesel knock. If yours doesn't change much as it warms up, then perhaps it is the different motor in the new 990s. When mine is cold, it almost doesn't sound like a diesel it is so smooth, but it also won't take much throttle without sputtering or hesitating a bit - almost like the extra fuel being injected is cooling things down too much in the cylinders and combustion gets a bit iffy. Let it idle for a few minutes and warm up, however, and it is like any other diesel I've heard or played with. Whether it is just cold cylinders at first or some fancy engine controls that I don't know about that are changing the injection timing or something, I don't know but that is how it behaves.

If I remember next time I go out to use the tractor, I'll record the sound when I first start it and then when it warms up. Can you post .wav files like pictures? I don't think I've ever seen one posted on TBN. Maybe I'll be the first! /forums/images/graemlins/smile.gif

 

[JayC]

I was just looking at a thread where someone had posted .wav files. Just make sure they are 100k or under and everything should be fine. /forums/images/graemlins/cool.gif