ZD30 DI Intercooler Upgraded Welded Unit

Nissan Patrol Zd30 Di 98-2006
Upgraded intercooler
Welded core with better flow

It is quite common for the original zd30 intercooler to split at the crimped tank ends.
To tell if yours is leaking you will normally see oil coming out of the intercooler.
It is a good idea to replace them when leaking as it can cause issues such as limp mode.
Having boost leaks can also lead to other issues, so replacing the cooler when leaking is a must.