Auto transmission effects exhaust note?

[uslspct]

Since I have an auto, I've noticed how the tranny effects the exhaust note, mostly in 4th gear.
Most people know when you're cruzin down the highway in an auto you're right at about the torque converter lock up rpms. The best way to describe it is you can feel it "catch" and then exhaust note changes. I can really tell the sound changes because my exhuast is loud and sounds like shit right now from an exhaust leak or something.
But my question is how can a tranny do this?

[accordaffair]

I don't think its so much the tranny, its the change in rpm coupled with the change in engine load.

I know that my exhaust tone sounds different from when I'm riding in it alone, cruising with the accesories off, versus packed with passengers, a/c on, etc

The tone is different under different loads, but its the engine making the noise, its just affected by whats attached to it creating extra duress.

[MikeW]

i can vouch for the catch followed by change...it like ill hear it shift all the way up, then right there at 4th it changes and kinda tones down so as to not be too loud. Seein as how i cruise around everywhere at about 35-50 thats right around where mine shufts to 4th so the exhaust tones down...so i just shift it to D3 and let it keep up that deeper tone. As far as how it does that or what makes it do that...ima say it just has to do with the fact that the tone will change with load/shiftage, and since you cant neccessarily change that in an AT, that happens.

[gloryaccordy]

A/T cars sound like they're crying

[cp[mike]]

A/T cars sound like they're crying

thats why they die so often, they know they suck, so they cry and get upset to the point where they become lethargic and clumsy and stop doing their job, and eventually throw in the towel...

[uslspct]

I understand saying when under a load it makes a certain sound. But how? There's pistons and valves moving air though the engine and then to the exhaust. What contributes to the exact tone?

[The G-Man]

It kinda sounds the same way in the manual when you put it in 5th gear. It sounds like a load has come off the engine. Because 5th gear is the overdrive gear, and basically is like the torque converter locking up.

I can tell on the exhaust note there is an automatic because it shifts faster, and you can hear those.

[uslspct]

Bump

I'm bumpin this because I want to know what would a failing AT would do.

I don't have any codes and it still shifts fine albeit it's never in the right gear, but everytime I accelerate it's like I'm not going anywhere because it feels like the power isn't getting put to the ground. And every once in a while when it gets to rev past 4k or so it will pull nice. Like out of nowhere it'll accelerate nice but everytime under 3.5k sucks ass. It's like my my car just chooses to show what it can do once in a blue moon.

But, I may have other problems as well. And it still sounds like ass.

[NAiL05]

I would check that torque converter then. IF low RPMs are NOT picking up at all then yea your torque converter aint workin properly. Is your D4 light and all that bs flashing or somethin.

[uslspct]

I would check that torque converter then. IF low RPMs are NOT picking up at all then yea your torque converter aint workin properly. Is your D4 light and all that bs flashing or somethin.

No it's not.

[NAiL05]

No it's not.

No lights around the trans flashing??? I would think it would tell you something but if nothing is happening in the low rpm aka full throttle no go until certain speed (usually 30mph or so if i remember) then yea tq converter usually isnt doing its job. Umm hows your fluid? Change it out? Does trans slip or anything when going into gear?

[uslspct]

Fluid is fine. Probably could be changed though, but I'm not because I'm getting rid of it.

Slipping is the key word. That's what it feels like when I try to accelerate, like the engine wants to rev but the tranny just wants to sit there and not make me accelerate. Like if it was a manual and the clutch wasn't grabbin the flywheel.

I think I'm gonna make a movie to record the sound, and see if it all gets picked up on the mic. Either way I can't wait to get rid of it.