thumping coming from under my car after lowering???

[Devens240]

ok. So i recently lowered my S13 hatch with agx struts and Eibach sportline springs. now when i sit at an idle i hear/feel this loud thumping right beneath the center console. it also happens when i turn to the right. are my tranny mounts causing this? thankyou
Deven

[alkemyst]

being it's center console, it could be. It could be a combination of motor mounts and tranny. I didn't notice my tranny mount bad until I did my suspension. Then every speedbump I could feel it in the stick shift.

[Devens240]

yeah its not so much in the stick. i can just feel something slamming against the undercarriage of my car when it idles low or i take a right turn fast

[JRas]

subframe bushings?

maybe check to see if the trans mounts are loose? maybe the mount is just worn.. could go nismo mounts

[Devens240]

i ust put energy suspension bushings in the subframe. but that wouldnt make it thump

[SexPanda]

Well, having a stiff subframe and stock tranny/ motor mounts, you could be having somewhat of a see-saw effect, with the tranny moving up and down, while the subframe is stationary.

You'd be suprised how bad tranny and motor mounts can get in those old 240's.

[HyperTek]

does your stick shift shake alot???

[Devens240]

the stick shakes some, im going to buy a tranny mount and put it in. should i go with nismo?

[alkemyst]

If you drive hard I'd go Nismo, SPL, etc...I like my Nismo.

[DMaxUSA]

Peak Performance Transmission Bushings are also good. They come in Street and Race versions.

[iHeartTheTouge]

Peak Performance Transmission Bushings are also good. They come in Street and Race versions.

i went with the Race version mount from Peak Performance, good stuff

[ericcastro]

I think Its your carrier bushing. Yes, you said you feel it at idle, but I would check it out too, since your gonna be down there.

If it is, one piece driveshaft for an extra $100.00 more than the carrier bushing job will cost.

Eitherway, you should jack it up and have a look, its easy enough.

[Devens240]

so if the carrier busing is bad it will move from side to side at the knuckle?

[Dream240]

Sounds like you got a mount problem. check your engine mount bolts to make sure nothing has come loose. Also to see if you need new mounts:

check the engine mounts by grabbing the sides of the engine and try rocking it. Do this while to car is shut off! Does the engine rock alot? Pretty easily? Also can you mimic the thumping sound by doing this?

For the tranny mount, if you've got no gap in the center between the two sections, get a new one. Nismo is the best IMO for daily driving and track use.

[ericcastro]

so if the carrier busing is bad it will move from side to side at the knuckle?

Yeah. So if its not the mounts. then its probably this. Have you had any exhaust work done lately? could it just be exhause vibrating agains he body?

[alkemyst]

My sway bar touches the body sometimes on a hard turn.

[Dream240]

Yeah. So if its not the mounts. then its probably this. Have you had any exhaust work done lately? could it just be exhause vibrating agains he body?

Well he's saying that the thumping is coming from the car at idle. The carrier bearing isn't rotating during idle.

The main cause for the driveshaft to be thumping against something is due to a bad tranny mount allowing the tranny to sag, thus allowing the front drive shaft to sag. Even if the carrier bearing is bad, the carrier mounting brackets will not allow that part to sag while stationary. Unless the two bolts holding those brackets are loose. The rear drive shaft piece would sag due to bad subframe bushings.

And if you've replaced those with upgraded bushings, you've raised the drivetrain UP. bringing it closer to the frame. Can create all kinds of rattles.

Good luck.

[Devens240]

ok thankyou for all the help. ill put it on on a lift at work tomorrow and check all the mounts.