I bought a used 5.3l from a 2004 Silverado, came with 119k miles. Note that some of the LS motors are DBW (Drive by Wire) and older ones are DBC (Drive by Cable). The pedal you choose will be dictated by the type you get. Mine was DBW, which means no throttle cable, its electronic.
Room was tight in front of and below my engine. I have read that you can use corvette accessories on these engines and gain a couple inches of clearance in front, but I was trying to keep a budget, so I used the truck ones. My power steering pump pulley was binding with the steering gearbox. I bought a Relocation Bracket Kit that moved my alternator to top right and power steering pump to top left. I deleted the a/c unit, as it wouldn’t fit underneath and this is not a daily driver. I could always add it back if I decide to down the line. I really like the relocation bracket kit, it is nicely made and includes everything. Unfortunately, the power steering pulley hit my inner fender, I could have just bashed the inner fender with a hammer, but I bought a smaller pulley, and installed it with a rented pulley puller/pusher from Oreilly’s. The alternator cable was now too short, I bought a Lead Extension.I needed a Serpentine Belt. This took care of my front end, leaving me about ½ clearance.
My oil pan hung about 4 inches below the bottom of the truck, not going to work! I bought a replacement Oil Pan Kit that was 4” shorter. It is much better and sits even with the bottom of the cross-member. I wish I had installed this before mounting the engine, it was a pain with the engine already mounted. Buy some kitty litter, you’re going to make an oily mess with this job!
Tune Up Items
I decided it was a good time to change Spark Plugs and Wireset while I was at it. I also grabbed some Heat Protection Sleeves, as the new headers are pretty close to the wires. They do not come with dielectric grease, which was odd, but I grabbed some HERE, I also bought some anti seize HERE. I was able to bend the wire enough that they didn’t touch the headers. I confirmed the plugs were gapped to .40, then torqued them to 12 ft/lbs. The wire-set I chose allows you to bend the terminals, to squeeze by the headers, which I needed on the front cylinder on both sides.
My MAP Sensor was busted off of the junkyard engine and I had to get a new one. It was busted too low though, so I had to remove the intake to pop it out, which means I needed new Intake Manifold Gasket. I cleaned the intake manifold as best as I could while I had it off.
Oil & Temp Sensor
I did have to add an oil temp sensor and coolant temp sensor to my gauges. The original ones on the engine, wouldn’t work with my gauges. I was given both sending units with my gauges. I added the oil sender to the cooler port above the oil filter, I bought an adapter HERE. I put the temp sensor into a hole on the rear passenger head top. It has a plug in there, that has an Allen wrench head, just removed and put my new one in using the adapter HERE.
Installing the Engine
You will need help with this, luckily for me, Dad was able to come over. I lifted it with a Shop Crane with the transmission attached. We put it in place and then the fun began. You need to level the engine on 3 different areas. It needs to be centered right to left, as far back towards the firewall as possible and 3 degrees tilted backwards.
To begin, get the engine as low as you can without touching the cross member, mine was about ¼” above it. I also bought a Magnetic Angle Finder, you will need this. I then placed wood shims in to hold everything as it was and started with the Motor Mounts. I attached the piece to the block then dropped a bolt in it and measure from the frame to the center of the bolt. I then cut the frame part to that dimension (2.5” for me) and set it on there. My frame tapered inwards, so I had to cut an angle from approximately ¼ of the width up ⅜”. I set this in and it matched my frame perfect. I then inserted the bushings and mounted it like it would be and tacked it to my frame. I then unbolted and pulled the engine/trans out. I then welded the mount all around and reinstalled the engine/transmission. This worked great!
For the trans cross member, I bought a piece of 1×2 steel tube and ran it underneath the frame. I drilled holes about an inch from each end and matching holes into the frame. Since the frame is boxed right there, I cut a hole in the side, just big enough to thread on a nut. My angle was at 6 degrees though, so I cut another piece of 1×2 about 6 inches long and placed on top of the bar. I cut large holes in the bottom 3, to allow for room when attaching a nut and welded it to the long bar. I now sit at 3.5-4 degrees down bubble. I used grade 8 ⅜” bolts for mounting it to the frame.
Transmission Cooler Lines
For the cooler Lines, I removed the original plugs by prying little black discs back then spun them out with a wrench, they were pretty tight and took a lot of time. The fittings are ¼ NPT, I went to Lowes and grabbed some ¼ NPT to ⅜ Barb fittings and put them in place. I used regular ole hose clamps for attaching the Hose.
I called Southwest Speed and explained what I was trying to do. The Guy seemed a bit annoyed and could tell that I was a Newbie, but he explained how to measure for the length I needed. He also had me count the number of splines on my transmission, there were 27. I called him back and gave the measurements as instructed and 2 days later I had my new driveshaft. The part that goes in the transmission was already installed (slip yoke) but the end that connects to the rear-end wasn’t. They did include a U joint for it though. I used a vise to press the U joint together and it worked perfectly. The measurements were perfect and I had a nice fit. I also decided to add a Driveshaft Loop, basically a steel safety loop to prevent the driveshaft of falling down to the road in case of failure. I bolted it to the 1×2 support bar under my cab. I highly recommend that, very cheap safety.
Cold Air Intake
I bought a kit, it didn’t work! I ended up just buying a 4” Elbow, a MAF, a KN Filter. I thought about cutting a hole in my inner fender and placing the filter in there for cold air draw, but opted to just keep it simple. It would be a simple enough change if I decide to later.
I bought a new 20 Gallon Tank, Tank Strap, Sending Unit, Filler Neck, and Hi Flow Pump. I hung the tank in the OEM spot on the S10. I then bought some Fuel Line and various fittings. I had to get quite a few fittings, so here is a set of links: x6 Here, x1 Here, x3 Here, x1 Here, x1 Here. You will also need a fuel filter and bracket. Here and Here. I ran the 2 cut ends together front to back, and first marked where I wanted to place the filter on the frame, then cut a short tube to go from the tank to the filter. I then put the hose end fittings in my vice and worked the hoses on. I went back to the truck and started tightening them down. I mounted the Fuel Filter, Bracket and installed hoses to it. I followed the frame all the way down and used rubber coated clamps every foot or so. I followed the firewall up, keeping as far from the headers as possible and came in from the top side of the engine and attached both to the fuel rail. This was an expensive route, but it’s much safer than several alternatives, being fuel, safety outweighs cheap!
I got my headers HERE. It came with the starter tubes and O2 bungs in each. I started putting them on and found that the driver front and rear bolt had been broken off inside the head when the Junkyard removed the exhaust manifolds. I tried welding a nut on the end and removing them, no luck. I found out that Dorman made a special device that clamps them and does not require pulling the head. I got the clamps Here and Here, they work great and saved me a pretty big headache. I bought everything from Summit for this project: Muffler, 3 Pipe Sections, 4 Hangers, 2 90 Degree Elbows, 2 45 Degree Elbows. I elected to weld it all together rather than use clamps. I crawled under a lot for this job, lots of measuring required, but well worth it. I was going to do an X pipe, but with the dual in single chamber muffler, it was not needed. I then just put some turn downs on the Cherry Bomb muffler. I would advise doing a few tack’s until you get the angles right before doing a complete weld! I used Offset Band Clamps to attach to the starter tubes from. These worked great and were easy to install.