Q: I have a 2002 buick rendezvous and I'm looking to possibly swap the 3400 for an lx9 3.5

asked by on March 14, 2017

I have the infamous GM 60° 3400 and I have yet to experience the mechanical hailstorm of the LIM gasket. As I figured it's only a matter of time before it arises, I thought about swapping to a whole new engine once I need to. I'm considering the lx9 3.5L due to the fact that it's very simular to the 3400 is terms of size and fit. I was curious what the advantages and disadvantages would be and if this would be a smart/recommended action. Thanks.

My car has 72000 miles.
My car has an automatic transmission.

Intake Manifold Gaskets Replacement $166.06 - $992.76 Get a Quote

The re-designed gasket (Fel-Pro, for example, in the aftermarket) for the lower intake manifold on this engine, and the revised installation procedure, provide a 100% effective resolution to the notorious leak issue that you are referring to. With regard to engine swaps, inasmuch as the vehicle engine is matched to the on board computer (hardware and software), all vehicle sensors and the vehicle wiring harness, it is not practical to substitute any engine that does not come up in a GM parts catalog as a direct, 100% compatible interchange. If you desire to install a non-interchange engine, you would have to change out the vehicle’s electrical system (PCM/ECM) which is just not practical. If you desire that the intake manifold gasket be updated, in order to resolve a current leak, or just as a preventive measure, please request lower intake manifold gasket replacement and the responding certified mechanic will get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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