Refreshing the 4.8/5.3
Refreshing the 4.8/5.3 My V6 Silverado has the dreaded intake manifold leak (again) as well as the rear main seal. At this point I am done maintaining the V6 and it is time for a V8 swap. I am looking to put in a 4.8/5.3 but refresh the topend. Looking for opinions on what I should be replaced and with what? Feel free to provide anything additional.
Lifters - Delphi GM LS7s with trays; is this overkill?
LS2 timing chain or resuse the stock?
Melling 295 oil pump or the 10295 high pressure?
Should I refresh the valve springs for a 150k-200k motor?
Would it be necessary for hardened pushrods or keep the stockers?
I am not going to do anything with the truck with regards to racing. It is my commuter. It will just have headers, ORY, and a cheapy intake. Thank you!
Lifters - Delphi GM LS7s with trays; is this overkill?
LS2 timing chain or resuse the stock?
Melling 295 oil pump or the 10295 high pressure?
Should I refresh the valve springs for a 150k-200k motor?
Would it be necessary for hardened pushrods or keep the stockers?
I am not going to do anything with the truck with regards to racing. It is my commuter. It will just have headers, ORY, and a cheapy intake. Thank you!
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No that should be perfect
LS2 should be fine
10295
Yes
Good PRs are only $100; no reason not to
Consider a cam. There's a couple in the 206°/212° range that would be a major upgrade in power without hurting gas mileage; Vinci has some near there, pretty sure TSP does, maybe the Summit 8718. LS6 springs such as from TSP would be fine. TSP PRs as well.
LS2 should be fine
10295
Yes
Good PRs are only $100; no reason not to
Consider a cam. There's a couple in the 206°/212° range that would be a major upgrade in power without hurting gas mileage; Vinci has some near there, pretty sure TSP does, maybe the Summit 8718. LS6 springs such as from TSP would be fine. TSP PRs as well.
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From: Louisiana
if you are able to find a pullout from a wreck in that mileage range, and all you want is a commuter, drop it in with fresh plugs, wires, and an oil/filter change and let her rip. I would pull the valve covers to see how well the owner serviced it.
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From: South Carolina
GMT-800 (99-07) Silverado truck?
If not disregard this info.
I did the V6 to V8 (LQ9) swap In my 2000 Sierra a couple years ago.
The V8 engine harness must match the year of the truck... either a (1999-2002) or (03+). Try to find the harness with the transmission PRNDL switch still attached. For some reason the factory glues the harness connectors to the switch and removing them usually damages either the harness or PRNDL switch. I had to buy a new switch when mine broke removing the V6 harness.
1999 and early 2000 V6 ECM's are the older "black box" and will not work.
The 99-02 uses a one pin oil pressure sensor, 03+ uses a two pin sensor.
You'll need V8 engine frame mounts, from either a 4x4 or 2x4 (depending on your truck)
The V6 hard liquid A/C lines are the same but the rubber suction lines are V8 specific.
New V8 A/C accumulator (V6 ports are in different place)
The V6 air filter box will work but you'll need the V8 tube.
The V6 alternator and power steering swaps over (with a PS pulley tool)
If you have a mechanical fan you'll need the V8 upper and lower fan shroud.
If you have a return type fuel system you'll need to cut both the supply and return fuel lines and adapt in V8 lines with unions (I used pre-made N2o braided lines). You'll also need a return type fuel rail on the donor engine.
If the truck is returnless and the donor engine has a returnless rail you're gold.
If not disregard this info.
I did the V6 to V8 (LQ9) swap In my 2000 Sierra a couple years ago.
The V8 engine harness must match the year of the truck... either a (1999-2002) or (03+). Try to find the harness with the transmission PRNDL switch still attached. For some reason the factory glues the harness connectors to the switch and removing them usually damages either the harness or PRNDL switch. I had to buy a new switch when mine broke removing the V6 harness.
1999 and early 2000 V6 ECM's are the older "black box" and will not work.
The 99-02 uses a one pin oil pressure sensor, 03+ uses a two pin sensor.
You'll need V8 engine frame mounts, from either a 4x4 or 2x4 (depending on your truck)
The V6 hard liquid A/C lines are the same but the rubber suction lines are V8 specific.
New V8 A/C accumulator (V6 ports are in different place)
The V6 air filter box will work but you'll need the V8 tube.
The V6 alternator and power steering swaps over (with a PS pulley tool)
If you have a mechanical fan you'll need the V8 upper and lower fan shroud.
If you have a return type fuel system you'll need to cut both the supply and return fuel lines and adapt in V8 lines with unions (I used pre-made N2o braided lines). You'll also need a return type fuel rail on the donor engine.
If the truck is returnless and the donor engine has a returnless rail you're gold.
RedXRay, really appreciate that info! I've got a 2000 so I know that I need DBC 99-02 motor, was un aware of the computer difference though. I will be using that info for my swap, thank you!!
None of that is “refreshing” an engine. None of that is even necessary plus it requires pulling the heads which is a major task in itself because cleaning off the gasket material takes a lot of patience and elbow grease. Just leave the damn thing alone and bolt it in because none of what you’re thinking about doing is going to add any longevity to the engine because none of that stuff is a failure point on a stock engine.
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From: South Carolina
Official NBS V6 to GENIII V8 swap Guide
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None of that is “refreshing” an engine. None of that is even necessary plus it requires pulling the heads which is a major task in itself because cleaning off the gasket material takes a lot of patience and elbow grease. Just leave the damn thing alone and bolt it in because none of what you’re thinking about doing is going to add any longevity to the engine because none of that stuff is a failure point on a stock engine.
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From: Central Cal.
You are arguing with my over semantics of what is technically refreshing. Provide some valuable insight or get out of here. Lifter failure is a common enough issue on gen III LS that I want to replace them. It isn't that hard to clean gasket material off. Get yourself some air tools and a plastic puck.
A fresh LS2 or equivalent timing chain, lifters, and oil pump will add life to your engine.
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From: Central Cal.