Need a GM 5.3L replacement engine, who do you recommend?

You mentioned you are in Cal, are you in S. Cal? I don’t actually know those engines, but between asking guys on here and Utube I’m sure it can be figured out.

 

There may be a tool or guage you can screw into where the sensor goes but check screen first. Then look at your wiring just in case its damaged. OP sensor is at the back of the valley (on right above #7 cyl). Check your oil level, fill to full, then pull screen reinstall sensor run truck. If pressure is same it may be oil pump or sensor. Obviously the sensor is the easiest and cheapest to change out/troubleshoot.

 

I've had a few of those oil sensors go bad. Easy fix.

 

It's a crazy process checking oil pressure. To check the pressure you have to run the engine, if there's a bad oil pump, running the engine will burn it up. I had an oil pump go bad on a 2006 GM 5.3. truck had 120k on it but overall a great truck. I found a used 5.3 with 100k on it on Ebay for $850 shipped. Mechanic charged $1200 to replace it. That was 10 years ago, I added another 60k trouble free miles on it, sold it 5 years ago, still going strong.

This was before covid, your pics may vary

 

https://www.stevemorrisengines.com/engines/sml-up-to-3-500-hp-water-jacketed-ls-based-engine

 

https://www.texas-speed.com/?gclid=EAIaIQobChMIgo_KwKGm-wIVZRPUAR2RngumEAAYASAAEgJSyfD_BwE

Look at Texas Speed and Performance...if my budget was open I'd be driving my engine down there for a refresh

By the way, I rebuilt my 5.3 in my 10 silverado with a Texas speed DOD delete kit. I refreshed my heads, match ground the valves to the heads and put in a new cam. Its a peach now

The gen 4 engines came with a different type of oil pump. It's not a pressure pump and as long as your in the mid 20's at idle (550-575 rpm) your good.

 

I changed the oil again in the Sub (head gasket issue was cooking it) and the oil pressure came up. Its now in the mid to high 20's at idle and right at 40psi normal driving. I guess thats alright for now. I am used to seeing higher oil pressure in my Cummins so it was freaking me out. I still think I'm going to pick up a salvage yard motor and start rebuilding it so I have something dialed ready to drop in when this thing kicks the bucket.

 

I didn't say that money was no object! Also I think a 3500hp Suburban would not be ideal for the wife.

 

I had a bad sensor on mine that was causing erratic oil pressure readings, and then it finally just dropped to zero while driving home in the rain one night. I said f-it, if it dies it dies and kept driving home, 90% sure it was just the sensor......It was....Changing it is easy....but it is also a bit of a bitch to do as it's blind. If that makes sense.

On mine I honestly think it was just the screen that was plugged and not the sensor. But after going through all that, the sensor was getting changed regardless. On a high mileage engine with prolonged oil change intervals, its most likely the screen.

 

Check your radiator flow, make sure it is not clogged.

 

All 3 of my GM trucks will show a lower pressure while idling, around 20 or so, give it a little throttle and it jumps well over 40. Pretty common.

 

That's typical for the 5.3...I started using Shell Rotella Full synthetic 5w30 in the truck. I just turned 195k on the odo and around 45k since rebuild. Project farm on YouTube had Shell Rotella as top notch. As soon as I changed to that oil my pressure was up to 30 psi at idle. After 5k miles it dropped to around 26 psi.

If you stomp on it and it goes between 40-60 your good.

Ticking of any type ain't your friend and would signal a rebuild for sure.

 

That oil pressure sounds normal to me also. I did have a valve spring let go on my 07 5.3 van a few years ago at 140 ish thousand miles. A fluke thing I think. I replaced all the springs on that side of the engine and fired it up. Been running fine ever since, a friend of mine is still driving it. Generally a great engine.

 

What year did GM go to the variable valve in the 5.3?

 

When its cold and the oil needs to be changed it develops a lifter tick. Goes away after the fresh oil goes in and the engine warms up.

 

Pretty sure 2007

 

I had a 2006 Silverado, with the 4.7, great motor,I was getting around 25mpg

Your oil pressure sounds good to me.

 

I think around that year 07, but not all vehicles. Vans for sure didn't get it.

 

Your Silverado had a Dodge motor in it?
GM makes a 4.8L.
Dodge had a 4.7L

 

That oil pressure is OK. But be aware there are some issues with an o ring that seals the oil pick up,to the pump and if it leaks you can get some air into the system and have low oil pressure. It’s an easy fix….just getting to the oil pick up is a giant bitch.