4L80E whistling in forward gears
 

hey i was wondering if anyone else had a whistling sound coming from their 4L80E when its at operating temp and in any forward gear. I have an 04 chevy 2500HD with a 6.0L. The truck tows and hauls a bunch about every other weekend. I have always done a trans service from 15,000-20,000 miles and never has there been anything in the pan except for a little bit stuck to the magnet. plus the trans temp has VERY rarely gotten to 200 degrees or a little above

Just seeing if anyone else had/has this condition and what the cause is.

ohh by the way the trans shifts fine and i have no problems with it knock on wood.

Thanks
71Rat

Sure it's not the rearend whining? Some other noise? I've never heard a transmission "whistle."

nope its the trans once you put it into a forward gear it starts this faint whistling sound, does it even while standing still at a traffic light. i have gotten out while a friend held the brake to walk around and crawl under the truck to find the noise and its coming from the trans.

Same
 

I am literally in the same boat i have a 2004 GMC 2500 6.0 and the tranny seems fine but theres a whistle that i only hear in forward gears not reverse neutral or park, is there an air line above the tranny i dont know about?

Congrats. You dug up a 13yr old thread.

But to answer your question, a number of 80e's "whine". This has been attributed to the straigh-cut gearset used.

If it's working ok, don't worry about it.

:D

well at least he used the search lol

Or was a victim of continuous scroll.

"does it while standing still at a traffic light"
aka nothing to do with the helical vs straight gears

A. make sure it is full of fluid. Low fluid will whine like this
B. how many miles? Pump bushing wear can make a noise
C. filter sucking air...if you service the thing every 15k miles, but don't replace the filter seal...it's possible it could be sucking some air.

Did you guys ever figure it out? Sorry to revive this thread once again!

75% of the time if it has a whine in gear without moving, ill put a new filter in and it goes away.
The other 25% of the time its the pump.