4L80E makes a hissing sound when in gear
#1
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The title sums it up - my 4L80E from a 2003 Express van makes a hissing sound when it's running and in gear. It makes it in both drive and reverse. When you put it in neutral, the hissing sound goes away.
I noticed it after driving for about 200 miles on the highway.
On a side note, I think my first gear is a little noisy too. It sort of whines like reverse in a manual transmission. I'm not sure if that's related or not.
Any thoughts?
I noticed it after driving for about 200 miles on the highway.
On a side note, I think my first gear is a little noisy too. It sort of whines like reverse in a manual transmission. I'm not sure if that's related or not.
Any thoughts?
#2
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Everybody's stumped? I was thinking maybe it has something to do with the trans fluid filter. Maybe the filter came loose and sucked itself to the bottom of the pan? I had some dents on the pan that I pounded out - maybe something else is going on down there?
#5
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Thanks guys. It might be my imagination, but I hear the hissing sound when the trans is hot. I will try dropping the pan and putting in a new filter.
Is there any other way to isolate it or isolate it to a converter??? I have HP Tuners so I can command the trans, etc.
Is there any other way to isolate it or isolate it to a converter??? I have HP Tuners so I can command the trans, etc.
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#8
TECH Junkie
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Did you really just revive a 7 year old thread?
Try the recommendations posted above...then if that gets you nowhere...start your own thread with detail
Try the recommendations posted above...then if that gets you nowhere...start your own thread with detail
#9
#10
TECH Junkie
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Have you tried any of the recommendations above?
They are good recommendations so try them first
They are good recommendations so try them first