Starter Question
 

Wll the starter from a 3.4 work on a 5.3?

Okay. that starter got sold, now next question, since the thing stopped moving:

How complicated is changing the starter on the 5.3?

I wouldn't imagine it would be too hard - then again I've not worked on a FWD V8. Starters usually have 2 bolts, a few wire nuts to take off, probably a plastic shroud where the starter connects to the pressure plate.

IDK I'm sure someone else has worked on that engine here. Sorry I don't have any specifics.

The starter is super simple to replace, but it's a bit of an oddball on the ls4.

Many cars hang the starter off the bottom part of the block so you have to get to it from the bottom. On the ls4, it's mounted up top.

Just unhook the battery, remove the airbox, remove the wires going to the starter (it's mounted to the top front of the transmission under the exhaust crossover), remove the 2 bolts holding it on, and then pop it off.

That last part can be the worst part by far. It's got two healthy size dowels (3/8" maybe?) for alignment just opposite the bolt locations, so it must be pried straight off and it will take some force to get it going due to corrosion, etc. You can try hitting it with a soft face hammer a few times to help break the corrosion free if it feels stuck.

Pried up? Down? To the left? The right?

And how in the hell do I get any leverage on it (or for that matter, remove it) with the exhaust pipe in the way? (Yes, I found it before I read your post.)

The dowels are in the exact same orientation as the bolts. So the direction you pulled the bolts out is the direction you need to pry (basically straight away from the trans). Any lateral movement will only make it want to bind up worse.

As for how to pry it off with the exhaust in place, have you removed the airbox? You gain a ton of room doing that and could get all kinds of stuff in from the drivers side end.

It's hard to tell you what tool to use since I don't know what your options are. I'd probably start with my 18" straight bar sitting where the airbox is, or I've got a 30" with a 90* on the end that extends a couple inches. I'd hook that under the starter and run the bar straight out of the engine bay.

If you're really worried about the exhaust, you could just take it off. No doubt it would give a ton more room and it's not that hard to remove. Just depends if you want to spend the extra time.