Tony’s express van engine upgrade/swap

[Tonyv__]

Nothing overly exciting but I’d like to post this process and pick some brains along the way.

Here’s my 2012 express 2500. It’s my work van but the most driven car in my fleet. Roughly 130k but loaded with a 4.8 with numerous oil leaks and a nice knocking sound in the engine. (That’s not my trailer, but I bought one very similar to it)

This wouldn’t be the first time I’ve had to crack open an engine in one of these vans, but I convinced myself, if I’m going to go as far as to try and rebuild the current engine, I’d be much happier going back to a 6.0 instead.

I just hope my current engine holds on until spring atleast.

———————————

Couple weeks ago I got the idea to look through insurance auctions for vans. I thought I found my unicorn. Van was rear-ended pretty bad, but had low miles. Front end was in great condition, figured I could sell off some parts if I wanted to or sell it whole to someone who parts out cars. Between the 10 or so vans that were set to close the auction in the next 12 hours, this particular van was the only one with no bids. So I thought maybe no one was interested. If I was to get it dirt cheap, it was estimated to be about $1000 delivered to my driveway. Well I waited till the next morning And put my bid in 5 mins before it closed. It jumped from $0 no bids to $1500 in a split second. Then it went into a 60 minute live auction, that I couldn’t participate in without a premium subscription. Meh. I was naïve to think I’d get it that cheap and that easy lol.

I moved on from that idea.

——————————

A week ago, I impulsively messaged someone about an L96 6.0. It was listed as a core, so I knew it wasn’t running. (I tend to gamble on things like this and had a good track record of coming out on top, not always though). The seller was someone I recognized, had a ton of good feedback, and sold a lot of gm truck parts.

He told me that the spring was broken and the push rod wedged itself between the rocker arm. Very possibly would run if I fixed the spring and rocker. However, no guarantee, understandably. I figured worst case scenario would be heads, best case, spring and rocker. So I shoot an offer at $600 and made plan to pick it up after work.

 

[Tonyv__]

At first glance, here’s the push rod at the very front rocker arm. Wedged between the arm.

This is the engine loaded into the van, I didn’t have a cherry picker yet so I had no plan on getting it out lol. Luckily the van is so low to the ground, I was able to slide it close enough to the edge and bolt it into an engine stand then kind of wrestled it out of the van.

Couple days go by before I even touch the engine. First thing I do is pull out the wedged push rod… well it’s bent pretty bad. Has me wondering if the lifter is damaged now. It didn’t take me long to see through the intake port that the valve stem was gone. At this point, the heads come off and I find a damaged piston. So I just started tearing into it

 

[strutaeng]

Cool. We bought a 2020 2500 Express 12 passenger van back in 2021 with about 5k on the odometer. My wife drives it for hauling the kids to school.

It's got the L96 6.0, now around 25k.

How many miles on your van? I'm assuming your transmission is shifting good?

These vans are underrated in my opinion. Mostly used as work vans around here.

 

[Tonyv__]

Cool. We bought a 2020 2500 Express 12 passenger van back in 2021 with about 5k on the odometer. My wife drives it for hauling the kids to school.

It's got the L96 6.0, now around 25k.

How many miles on your van? I'm assuming your transmission is shifting good?

These vans are underrated in my opinion. Mostly used as work vans around here.

130k, But a lot of hours. they must idle a lot. Trans seems good. And I agree, I really like them when they run lol

 

[Tonyv__]

I am curious on what this might be though. This was sitting on the piston.

I’m thinking it fell into the intake port because idk why else it would be in the engine.

 

[SpareParts]

It is a safety clip holding the fuel line together.

 

[strutaeng]

Yep, fuel line connection clip.

If it would have fallen in there while it was running, you'd have a hole on the side of the block. LOL

 

[Tonyv__]

It is a safety clip holding the fuel line together.

Yep, fuel line connection clip.

If it would have fallen in there while it was running, you'd have a hole on the side of the block. LOL

gotcha. Just wanted to make sure it wasn’t something that needs to go back before I get the heads back on eventually.

The engine didn’t have an intake on it so Im
Assuming it just fell in.

 

[Tonyv__]

The valve really beat that piston up, almost pushed all the way through.

I would like some opinions and feedback. I’m not sure where to go next. Do I just buy a piston, rings, valve, spring, push rod, lifter and the associated gaskets and then send it.

the engine SUPPOSEDLY has 90k on it so still young IMO. But is there a way to check if the oil pump is still good before I swap the engine? What else should I look for?

And what are some absolute “must do’s” while I’m in there? Should I replace all the springs or just the Broken one? Do I replace all the push rods? All the lifters? Valve seals?

 

[Tonyv__]

My shopping list currently
- 1 oem piston
- 1 set of rings
- bolts for connecting rod
- 1 push rod
- 1 spring and retainer
- 1 lifter
- 1 intake valve
- set of head gaskets/bolts
- spark plugs/wires
- oil pan gasket
- valley pan gasket
- oil pick up tube gasket
- temp sensor
- oil pressure sensor

 

[SpareParts]

At 90K it should be in good shape. That being said here is what i would probably do to the block.
Are the cylinders in good shape?
I would at least re ring it since im already just about there. A new set of rings are not that much really, under $150
Having the pistons out will also let you see the piston skirt wear. If the coating is worn off i would get new std pistons. Under $300. If most of the coating is still there just reuse.
I would also replace the cam bearings, mains and rods.
New timing chain and tensioner
Inspect oil pump. Any scratches inside? Replace it.
Clean everything really well.
Not the cheapest way but should be good to go for many many miles

 

[Tonyv__]

At 90K it should be in good shape. That being said here is what i would probably do to the block.
Are the cylinders in good shape?
I would at least re ring it since im already just about there. A new set of rings are not that much really, under $150
Having the pistons out will also let you see the piston skirt wear. If the coating is worn off i would get new std pistons. Under $300. If most of the coating is still there just reuse.
I would also replace the cam bearings, mains and rods.
New timing chain and tensioner
Inspect oil pump. Any scratches inside? Replace it.
Clean everything really well.
Not the cheapest way but should be good to go for many many miles

1 side of me is telling me to do it all or not at all. It’s the bearing clearance and stuff like that, that makes me nervous. Assuming everything is stock. Do I buy standard size bearings, rings etc? I see a ton of measurements, oversized, etc. I dot understand that stuff

 

[S33k3r]

My shopping list currently
- 1 oem piston
- 1 set of rings
- bolts for connecting rod
- 1 push rod
- 1 spring and retainer
- 1 lifter
- 1 intake valve
- set of head gaskets/bolts
- spark plugs/wires
- oil pan gasket
- valley pan gasket
- oil pick up tube gasket
- temp sensor
- oil pressure sensor

You might want to look at a melling oil pump from Summit. It comes as a kit including the o ring and I think a pick up tube.

 

[SpareParts]

1 side of me is telling me to do it all or not at all. It’s the bearing clearance and stuff like that, that makes me nervous. Assuming everything is stock. Do I buy standard size bearings, rings etc? I see a ton of measurements, oversized, etc. I dot understand that stuff

Well here's the thing. It was running when it broke so it can't be that bad a guy would think.
Bottom ends on LS's are known to be pretty tough and long lasting. With 90K everything should be good.
Looking at your pics that engine looks like it has 190k of rare maintenance. There is going to be ware regardless of 90K or 190K.
If i did not have the tool's to measure, i would assume that new standard size stuff can't make it worse and would have to be an improvement.
Parts don't have to be perfect just close enough to work good enough.
Right now you have no idea what the oil pressure will be, did it smoke when running, did it use oil. No way to know.
With the new parts you at least know it should be good to go. If you buy new parts like rings, bearings, pistons just make sure you order std=standard size, but be sure to check the old parts to make sure they are original parts.

I'm not trying to talk ya into anything it's just what i would do if my buddy needed help and trying to keep it cheap and not do a full rebuild with machine work.

 

[Blackcar]

I didn't see valve head just valve stem that drilling piston I also would worry about valve guide being bad in head also.

 

[Tonyv__]

Well here's the thing. It was running when it broke so it can't be that bad a guy would think.
Bottom ends on LS's are known to be pretty tough and long lasting. With 90K everything should be good.
Looking at your pics that engine looks like it has 190k of rare maintenance. There is going to be ware regardless of 90K or 190K.
If i did not have the tool's to measure, i would assume that new standard size stuff can't make it worse and would have to be an improvement.
Parts don't have to be perfect just close enough to work good enough.
Right now you have no idea what the oil pressure will be, did it smoke when running, did it use oil. No way to know.
With the new parts you at least know it should be good to go. If you buy new parts like rings, bearings, pistons just make sure you order std=standard size, but be sure to check the old parts to make sure they are original parts.

I'm not trying to talk ya into anything it's just what i would do if my buddy needed help and trying to keep it cheap and not do a full rebuild with machine work.

I’m not exactly stuck on cheap. Initially I was really hoping to get lucky, throw a spring on it and save the engine. It’s not looking that way now. I need something reliable especially because this isn’t a project car but my work van.

I’d love to not go as far as sending the block and heads to the machine shop because at that point, I’ll be in the ballpark of a Reman engine anyway. I’ll take these comments into consideration as my current engine still runs so I have some time.

I didn't see valve head just valve stem that drilling piston I also would worry about valve guide being bad in head also.

the valve head is MIA. Good point I’ll have to watch up on some videos to see if that’s something I can evaluate and fix myself or requires a trip to the machine shop.