Have a 2011 JKU, had an AEV kit 5.7 swap done in 2012/2013 by OK4WD.
They did a good job but everything mechanically about the kit has been one big disaster with multiple issues, ironically all after the warranty ended.
Fast forward to now, and I need to start doing the work myself because all these repairs have become stupidly expensive, unfortunately OK4WD has not been very helpful with giving me all the motor info needed in order for me to get the proper parts whether now or in the future.
It's a Chrysler hemi.
Is there a serial # somewhere on the block?
Are all 2012/13 Chrysler hemi' s the same when it comes to headers, water pump, etc? Is a hemi a hemi no matter the year?

The biggest issue I'm facing that has yet to be fixed even after spending a total of about $10k is that the coolant is burning up in a cylinder, eating away my exhaust and smelling lousy! An engine warning light code says something about pressure (I believe) in a cylinder. And now I'm looking at another $3k to replace the whole exhaust, just to be eaten away again. Obviously, I'm not going to do that. And I'm bypassing the Cats this time.
I've replaced the whole exhaust system twice, whole coolant system once, Cat's 3 times and just now the pipe had been eaten away by the muffler, needing to weld a connector to put it back together.
AEV has been no help, as you can image.
I'm taking over but again, need motor info.

Whatever help you can offer, is greatly appreciated.

 

So I wouldn't drive that thing AT ALL with what you're describing. If the DTC is low cylinder pressure and you're burning coolant, you've likely got a blown head gasket.

As for engine identification, I've been told the identifying numbers are stamped on the block just above the oil pan rail on the passenger's side like for example: 4N5.7LTK030410508

My take is: the 4 is the year, N the country of origin, LTK (light truck), the rest....production sequence numbers.

The thing to remember (just like with Chevy engines) is that you can interchange much of the parts between applications. For example, above is a 5.7 Light Truck hemi... but they could switch out the intake manifold and heads for something off of a car.

They really should tell you what application your engine applies to. The L96 in my jeep is from a 2010 Suburban 2500HD for example. So engine parts (and oil filter) are purchased using that information.

Good luck.

 

The Hemi used in the AEV swap is for the Cherokee series vehicles. I have a 6.4 liter for the SRT 8 & the truck exhaust is used instead of the tube headers for clearance. Was yours a new crate engine or a take out used one? The engine used typically needs to be a similar year as the vehicle for emission certification. The 5.7 is typically a very dependable engine and gives a long service life.

 

I believe most states require the same year or newer so that it meets or exceeds the emission standards for the vehicle year.

To the original question, blown head gasket sounds like a potential winner on the coolant/pressure issue. Have you done any diagnostics, like a leakdown? Even pressuring up the cooling system should give you a point in the right direction, although it sounds like you're already on it.

 

Before you spend any more $ address the coolant in the cylinder. Until this is fixed you will continue to sink money into symptoms of a cause. Hopefully as mentioned above it is just a head gasket and not a cracked block or head.

You could do a Hydrocarbon test but if coolant is coming out the exhaust that would be moot.

Have the heads pulled and inspect the block and heads for damage. Once the coolant issue is addressed your other problems may go away.

 

Thanks for the advice.
Allegedly Ok4 had performed a head gasket test but i never saw the numbers, no reason to lie. Im going to remove the heads soon myself.
I had a similar experience with my old Freightliner, spent gobs of dough to find out it was a water pump gasket, ended up blowing up the radiator...that was fun! But I replaced the water pump.
I'm terrified it may be a cracked block.

So, ok, once I figure out the issue, do I look for 2011 grand Cherokee 5.7 hemi headers, 2011 JKU exhaust? Same connection headers to exhaust?

Meh...screw it. I'm gonna take it to someone around here.