Do 4L-80Es whine in first gear?

[Pinger]

Mine does - is that normal?
Low mileage truck and recent full oil change (it whined before that anyway) and doesn't seem to be misbehaving in any way. Oil level is correct.

 

[stutaeng]

Yes. Normal.

 

[Pinger]

Yes. Normal.

Phew! Relief - cheers!
I was a bit worried about an overactive pump (having had hard shifts before due to lack of MAF and had put the whining down to that until I noticed it again).

 

[1ton-o-fun]

Mine does.

 

[stutaeng]

I did fry a 4L80e not that long ago. I left a foreign piece of tape inside the pan and the filter sucked it up and starved it for fluid.

The last time I had driven it I did hear a whine, but was louder than usual and also in second gear. Haven't torn it down to inspect it, but pan was full clutch material, so not good.

The whine is from the sun gear. I believe the TH400 also does this, as it's basically the same parts. The straight cut sun gears on the TH400 that came with motor homes is supposed to be louder. But I've never driven one, just what I've read.

It's very noticeable when driving in parking garages. I kinda like that little whine, lol.

 

[Pinger]

I hear it in the village - cramped streets with hard sound reflective walls just feet away - and it is pretty loud but ends as soon as it shifts into second. I might come to like it now I know it isn't the pump trying to pop the transmission.

Pretty amazed how much better the transmission is for getting the MAF functioning again. Drops a gear when needed and I can force upshifts and hold them just by playing with the throttle pedal. Without the MAF it would drop a couple of gears with just a light touch of throttle and be up at 5000rpm with nowhere to go. And no more hard upshifts.
These trucks can drift quite a bit from optimal and still be usable. The closer they are to being as they should, the sweeter they are.

 

[RichLo]

Mass Air Flow sensor did all of that?

 

[df2x4]

Interestingly the 4L80E I swapped into my red truck doesn't do this, or at least if it does I've never noticed it. I do have a decently loud exhaust setup, maybe I just need to listen closer.

 

[1ton-o-fun]

It's not an obnoxious whine, just enough to let you know that it's a heavy duty transmission. Since my other car's transmission could be described as a bag of mashed potatoes, it's comforting to hear metal gears and feel every single shift when I'm in the truck.

 

[L31MaxExpress]

4L80Es whine a bit but 85Es are much more noticeable. This one is an 85E.

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