[THXdts]

I have been having a horrible exhaust rattle for the last 3 months, and just now crawled under the truck to see the primary cats cover in black dust. What is the easiest way to replace them? Obviously without putting another catalytic converter in.

 

[joefrontier2]

You can remove the heat shields with no problem. Most every 1st gen has them removed now as they rust off.

Also these are not the primaries these are the secondaries. We have 4 cats on these trucks. The primary has to stay as there is an 02 before and 02 after the cat. SOme have removed their secondary cats already but if you are in a state that does emission testing you may have an issue.


You also have only 1/2 a heat sheild looks like you lost the other 1/2.

Also you will want to check out this under your truck too as it will also rust and cause ratteelling. It's the flex joint in the picture below. Looks like a little can.

 

[THXdts]

You can remove the heat shields with no problem. Most every 1st gen has them removed now as they rust off.

Also these are not the primaries these are the secondaries. We have 4 cats on these trucks. The primary has to stay as there is an 02 before and 02 after the cat. SOme have removed their secondary cats already but if you are in a state that does emission testing you may have an issue.


You also have only 1/2 a heat sheild looks like you lost the other 1/2.

Also you will want to check out this under your truck too as it will also rust and cause ratteelling. It's the flex joint in the picture below. Looks like a little can.

It looks like you would have to put a 45 degree piece in to replace the cats?

 

[joefrontier2]

Yes, you would have to have someone fab up something for you (unless you are good with metal fab).

 

[massbaster]

4 cats not 2

while this is true there is a catch.

on some models like mine the exhaust manifold and primary cat are one piece.

that means that when i have to replace my primary cats i need to replace the manifold as well.

there is also the set up of primary cats that bolt to the manifold.

in this case i believe people are having trouble finding one side or the other.

then you still have to deal with the secondary cats,

from what i have priced out so far from genuine nissan parts, having the manifold and cat as one part is cheaper than have it seperate from the manifold. (by hundreds)

trust me i do not want to replace my manifolds BUT at the cost that it would be to get seperate manifolds and cats i have no choice but to get the manifolds and cats as one

BUT i plan on deleting the secondary cats and spacing out the o2 sensors.(this works i can confirm it)(antifoulers)