Clay Belt

I own a 2005 Buick LaCrosse CXS, and want to put a V8 into it. I know the LS4 is my best bet, but cannot find any around here. My current engine burns oil something horrible (1/2q every 500 miles on a 222k engine) and I need to do something soon. It has a new transmission on it (<2000mi), so I don't want to just sell it. I read somewhere that the 5300 Vortec engine is the same as the LS4, but has a 13mm longer crankshaft. Can I modify one so that I can drop it into my LaCrosse?

m1a2d3

the swap would costs much money i would just drive the car adding oil till it blows up. and then move on to something else

Clay Belt

Honestly,I would move onto something ordinarily, but I am looking for A) experience gained in engine swapping and B) keeping a car that has sentimental value on the road. The V8 would be a plus.

Bryan921SS

First and foremost what transmission do you have?

Is it the 4T65-E or 4T65E-HD?

The LS4 cars came with the HD heavy duty transmission and even then those break at some point in the car's life. Also the LS4's use oil too, not that that great of a rate but just FYI.

The V8 swap would be easiest with an LS4 from a donor car if you want to go that route. The 5.3 Vortec engines are not the same as the LS4, they are the same displacement but that is really about it. Also I believe any other LSx block will need a spacer/adapter to work with our transmissions to make the bolt pattern work.

I would pull the 3.6 and tear it down, replace the piston rings that are most likely the cause of the issue and re hone the block. That would still be a fun project and you would learn a ton about how engines work and are assembled!

Clay Belt

I don't know what transmission is in my car.

rottonj

iTrader: (4)

Finding out is a good start.

Clay Belt

How do I find out what transmission I have? VIN tells me it's a 4 speed online, buts that's no help. The data plate in the glove box is missing, so if it was on there, I don't have it.

Bryan921SS

I would think your car uses the 4T65-E based on the fact that you have the 3.6 liter LY7 engine.

If it was an LS4 or L26 car then it might have been the 4T65E-HD.

Check the paperwork from your new transmission that was installed, it should say what type it is.

fieroguru

iTrader: (1)

The 3.6 uses the GM High Feature Bellhousing and the LS4 uses the GM Metric Bellhousing, so you would need an adapter plate (and other work) to keep the transmission in the car.

It would be easier to pull the 3.6 and transmission and install the LS4 and its transmission with the built in starter mount.

Mike The Canadian

swapping sub frames would probably be the easiest bet from a hardware standpoint; no idea on tcm/ecm

'pacheMarshal

GM shortened the crankshaft 10mm and the other part 3mm. the engine bay is filled up, and I doubt a 5.3 rwd engine would fit without a lot of custom work. plus, many of the rwd 5.3's are iron blocks with iron heads, so would be much heavier than the all aluminium LS4.

Even if your LaCrosse has the 4T65e, the LS4 doesn't quite work with that transmission because the starter is mounted differently.