Odd Driveline Vibrations

I'm getting some driveline vibrations from time to time in my S14 SR20 swaped 240sx. More info... I also had an Auto to Manual swap done as well. I'm changing out the rear seal in my tranny because it's leaking a little bit.

Question: Could a blown seal be causing the vibrations?

Any help or ideas would be great. Thanks.:banghead:

Did you get a correct length drive shaft when you did the auto to manual switch?

Did you get a correct length drive shaft when you did the auto to manual switch?
It should be the right one. I had a shop perform the swap for me. I wanted it super clean.:iceslolan

It came from a 1996 240sx (used)

UPDATE:
Problem solved. Thanks guys. I had the seal replaced and it took care of the issue. Now if this new one blows out soon... I might have to give the barring on the tranny output shaft a little love.

its definitely a driveshaft problem. I had the same kind of thing happen. it's kind of like something's loose when you slow down or change gears, it clunks. You may want to get that driveshaft checked to make sure you have the right length, and also check where the drivesdhaft meets the differential for any play. Does it vibrate more when it's wet outside? like rain or anything?

:banghead:
Ok, It's started again. Here's the thing... it's vibrating when the car is at a stand still. This along with the fact I can hear the exhaust heat shield rattling against the exhaust pipe has me thinking it might be my Megan down pipe moving and vibrating. I know this is not secured to the chassis. I'll give you an update when I get it in the air tonight.

I bet you its your catalytic converter or the o2 sensors in it. Get underneath your car and with the palm of your hand bang on the cat. if it makes a rattling tin sound then you need a new cat. I bet you its that.

The rattling sound will sound similar to your loose exhaust pinging sound.

Thanks for the heads up. I'll be sure to check that out when I get in on my dads car lift tonight. Would the bad Cat cause the vibrations? Or is it like I'm thinking... that it's the down pipe?

More info for you: The vibrations started getting really bad after I installed my Silk Road exhaust manifold. Could this cause more flex and turbo movement when it heats up? :confused:

Thanks for the heads up. I'll be sure to check that out when I get in on my dads car lift tonight. Would the bad Cat cause the vibrations? Or is it like I'm thinking... that it's the down pipe?

More info for you: The vibrations started getting really bad after I installed my Silk Road exhaust manifold. Could this cause more flex and turbo movement when it heats up? :confused:

If you're using the stock cat off of the 240sx, then when you turboed your car it probably fried your cat or the 02 sensors in it.

The stock cat off the 340sx isnt a high flow so thats what would have caused it. the new manifold allowing more exhaust flow probably just topped it off. If the cat is upgraded though it's probably something else. I dont know, check anyways, if it does what i mentioned above then just gut the cat :)

Ok... I got it figured out. First, my cat is fine and it's an older aftermarket one. (Calsonic) I'm going test pipe as soon as humanly possible. Figgin' Cats!

The vibration was caused by the down pipe changing the angle of my exhaust piping. This caused the pipe to smack against the under side of my floorboard also hitting the heat shield. I made a bracket to hold the exhaust piping in place and away from where it was hitting.

Thanks for all your help.
:)