After recalibrating my tranny valve body and installing a new exhaust system from the cat back using 2 1/4" pipe, I get a loud "thump" during hard shifts. I removed the crossmember behind the exhaust resonator which helped, however, the noise remains. My tranny guy and the local Nissan dealer mechanics confirm that it's the exhaust system hitting the undercarriage. Any suggestions?

 

After I installed my headers on my car I had the same problem. I kind of rigged mine to stop banging by getting a hose clamp a bracing it to the cross member I believe. If I had a pic I would show you. Basically just find something that stays permanent to the car and try to clamp it to the car. I wouldn't recommend my method, I think an actual exhaust clamp would be better. Anyway, hope this helps.

 

I would not recommend doing this for one major reason:

VIBRATION

IF you clamp an exhaust pipe to the undercarriage vibrations in the gas pedal and cabin will be increased. The only option is to take the car to an exhaust shop and have them weld in hangers

Please do not "clamp" anything unless you want your car to be ghetto.

Mark

 

In the 2K/2k1 there are 2 cross members. One by the Y and one behind the resinator. I would check these. Also check the clearance to the rear axel, especially if you have lowered springs.

To fix, I would put the cross member back on but but longer bolts and some washers on. Or else you can losen the bolts on the pipes and try to arrange them so they do not hit, you may need to take one off and bend it a little.

 

Thanks for the help.