looking swap info

[jdmser]

I've been searching and all I seem to find are "it can't be done" or "the swb has a different frame" threads or "go search" threads. I have a 03 EXT with the 4.2 and want to go to a built 5.3 or fresh rebuild lq4. I'm done with the 6 so turbo,build,supercharged is out of the question. Where should I look for info where people actually know what they're talking about?

[mason10198]

There is one person here I know of who has done it, because I remember he spent forever on the wiring nightmare. Can't remember who it was though... You should be able to find that thread with a search.

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[AWCougar]

There have been a few people that have done the 5.3 swap. Gmtnation has a lot more on the swaps because of its more diverse crowd

[CHEVELLE598BB]

I have done numerous ls swaps. They aren't bad if you have access to good wiring diagrams. I haven't swapped an envoy or trailblazer yet but I have everything ready too. Unless i talk myself into doing a Cummins 2.8 four cylinder turbo diesel swap. Not sure yet. Im waiting for my 4.2 to die.

[rayluniewski]

The rainiers and saabs had a 5.3 short wheelbase option.


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[bartonmd]

As long as you're swapping in a gen-3 small block, you just have to change the wiring for the engine/ECM/TCM. If you're going to an LH6, they're CANbus, and you have to swap basically the whole wiring from the donor vehicle, inside and out. The frame is just cutting where the trans crossmember mounts and welding it back a couple inches farther forward, then new drive shafts, swap the rear end out from the donor (8.6 vs 8.0), and of course the radiator/shroud, and the bell housing for the trans. IF you have a complete donor V8 TB, it's just swapping parts and wiring and stuff over, and some welding. If you're trying to piece it together, it's a lot harder.

Mike

[jdmser]

Do either the Silverado or swb harness' work in the EXT or are they all proprietary?

[bartonmd]

The Silverado almost certainly won't. The EXT harness probably will, as long as you're talking about the same year ranges.

Mike

[escapepilot]

If you really want a 5.3 in your EXT, you would probably save yourself a ton of time and money by finding a junkyard EXT V8 and getting the whole thing. Then you'd have engine, mounts, radiator, harness, etc. I know the radiators are different because I had to modify the radiator brackets in Mark's 3" body lift to fit the 5.3 radiator.

Where are you located?

[jdmser]

I'm about 45 minutes west of St Louis. I've been looking for a salvage 5.3 ext for a while now. That's probably the way I'll go.

[escapepilot]

...I've been looking for a salvage 5.3 ext for a while now. That's probably the way I'll go.

Like this??? (some parts have been sold already)

[CCTB]

I just bought an 05 4.2L engine from http://engine-transmission.com/ and it came with a 5 year warranty and all the sensors needed, however it did not come with a/c compressor, alternator, and i had to swap the flywheel, intake, throttle body, oil pan, thermostat, and water pump in order to not void the warranty