Knock Under Car

I haven't gotten a chance to look under the car yet, when I'm home from school next week I will, but there's an a knock coming from under the car, towards the front. It mostly happens when I shift, especially a relavitely hard shift. When i turned my music off to listen to it, I did a little experimenting, and you can hear it when I push the clutch in, but only going into and out of gear (not when the car is in neutral and I just push the clutch in and out). Also if I like tap the gas when it's in gear, enough to make the car lunge a little, i can hear it knocking back and forth, maybe 4 times or so. Any idea what it might be?

engine mount?

hmm, didn't even think of that, but makes sense. Any other ideas?

hmm, didn't even think of that, but makes sense. Any other ideas?

You want more?

CV axles
Suspension mounts/bushings/ball joints
Radius arm bushings
Shift linkage

Does it happen when turning?

I would jack up the side that you think it is coming from and see if anything is loose. Move the tire forward backward. In and out on the top and the bottom of the tire. and so on.

You asked for it.

Good luck
SH

No, it doesn't happen when turning. It's not coming from a side, it's coming from dead center underneath. The axles were just replaced less than a year ago. It's not from the suspension. I plan on jacking the car up when I get home, I just wanted an idea of what to start looking for, if it's not staring me in the face when I jack the car up. Thanks for the other possibilities though.

I had a similar noice in my old motor, it could be a bad throwout bearing in the tranny, not for sure but its a possibility, thats what it was in mine.

a bad inner axel makes a clunk and doesnt make a noise while turning like the outer axel, also a mount could do this.. does your shifter move at all when you shift? if so your mounts probably broken in 2

i had that clunk and the jerking when i tapped the gas after coasting and it was the trans mount.

if you got some one you REALLY trust you can have them put the car from drive to reverse a couple times while with the hand brake on and giving it some gas and try not to stall while you look at the trans movement and axel movement, if you got a noise it will probably present its self

My axels were replaced about 10K miles ago, at most, so it shouldn't be those. Also my car is a manual, so that test wouldn't exaclty work for me. I'm home now, so as soon as I get some free time I'll jack that car up and have a look.

It could possibly be a heat shield that is coming loose. I heard a sound from under my car (Back in the day) and I was like WTF? and all it was was the heatshield on the exhaust manifold.

Does it grind when you shift, even with the clutch all the way in? If it does then it might be what JDMcivicEG said. It might be a synchro. That is, if you weren't sold a faulty part and it was put in, that could also be it.

Nope, no grind at all. It's literally a rocking sound, like something moving back and forth. It's actually been happening less, and I was thinking it might be something loose with the exhaust.