KTruck75

I have a 2007 Suburban with the 5.3L. Second owner. It had 7,000 miles when I bought it. As of yesterday, it had 322,081 miles on it. I do all maintenance and repairs myself. I've always run Mobil 1 fully synthetic. I did the AFM shield, new valve cover design and cylinder soak around 190,000 miles due to some oil consumption which resolve the problem. It's a very solid engine and I don't see any reason it wouldn't do 500,000 miles +.

2007 5.3L Suburban LTZ with 200,800 miles. I've owned it since it had 7,000 miles and have always used Mobil 1 fully synthetic. I started to notice some oil consumption at about 150,000 miles. I typically change the oil about every 8,000 miles or when my wife tells me it's saying it's time to change the oil. One day, she decided to take it upon herself to just reset the oil change indicator when it said it was time to change the oil and not tell me. I get a call from her one day that the suburban is showing the engine oil low indicator. So I check my records and it's been over 12,000 miles since the last oil change...WTF! That's when she told me she had been resetting the change oil indicator and not telling me. She's lucky this car tell us the oil is low, otherwise, she'd be driving my beat up '99 intrepid if the engine seized! I figure it's burning 1 quart every 4,000 miles now as it's usually down about 2 quarts when I change the oil at 8,000 miles. I may throw a catch can on it to see how much blow-by it happening. I replaced a bad oil pressure sending unit on it today and had to remove the intake to get to it due to the rear sound dampening cover in the way. There was a little coating of oil in the intake but it also has 200,000 miles on it. I have the newly designed valve cover to install along with some GM top end cleaner to clean the rings but haven't gotten around to that yet. I'm hesitant to install the AFM deflector shield as I hear a special alignment tool is required to properly align the oil pain.

I have a 2007 5.3L Suburban LTZ with 200,784 miles on it. The oil pressure was sitting at 0 and was occasionally dumping to 80 and back down to 0. I replaced the oil pressure sending unit in it today. The intake manifold on my 5.3L has a sound dampening cover on the back that's bolted on and the brake booster hose runs through it. This makes it very difficult to get to the oil pressure sending unit. I have a snake camera and probably could have replace it without removing the manifold but it wasn't worth the aggravation. I've read of others with the back cover using u-joints and extensions to replace it but it's really tight. I'm 6'5" and I couldn't reach back there even when standing on a ladder. Disconnect your battery first. It didn't take very long to get the intake manifold out. The hardest part was removing the fuel injector connectors. The plastic has hardened making them not work as expected. You're supposed to be able to slide the connector up and push then pull the connector off but I couldn't do so. There's a youtube video on how to get them off: . I left the fuel rails attached. Make sure to remove the fuel rail pressure. Next, use use a fuel line removal tool to pop off the fuel line. Plug the fuel line from the fuel rail if you don't want gas pouring out. I had a little rubbery cap that I slid over the tube. Works great. Remove the positive cable from the alternator as it's in the way (Disconnect the battery first!!). After you have all the connectors disconnected and tubes removed, remove the 10 bolts holding the intake manifold to the engine. You should now be able to pull the manifold out. You now have easy access to the oil pressure sending unit and filter. First thing I like to do is place rags or paper towels in the intake holes to keep debris and parts from falling in there. Remove the oil pressure sending unit and discard. Don't reuse the old one because if you do and the problem persists, you'll have to take it all apart again. The filter is tiny and my fingers are big so there was no using my fingers to get it out. My 11 year old daughter wanted to help at this point and offered to stick her fingers in the filter to get it out but I decided to use a different method. Some people use a curved awl to get the filter out. If you are reusing your filter, the awl will most likely damage it. Instead, the filter has two protrusions on the top that we'll use to get it out. using needle nose pliers, I gave the filter a twist to make sure it was loose then gently grabbed one of the protrusions with it and it came out no problem. I've only run Mobil 1 Fully Synthetic since I got the car with 7,000 miles on it. The filter was completely clear with no sludge or any other debris. I sprayed it out with some brake cleaner, dried it and popped it back in. Replace yours if damaged or if you don't feel comfortable reusing it. Next, put some sealant on the threads of the new oil pressure sending unit and install it. I believe the torque was 26 ft. lbs. Clean the area around the intakes. I vacuumed everything out good first as some rodent put tiny acorns all up under the intake manifold. Inspect your intake manifold gaskets and replace if needed. I cleaned and reused mine as they were fine. Installation is the reverse of removal. The intake bolts have a specific sequence and two stages of torqueing them down. I believe the first round is 44 in. lbs. and the second round is 89 in. lbs. Double check that you have everything hooked back up, reconnect your battery and fire her up! Check for leaks and if all is well, take her for a test drive. It sounds like a lot of work but it's really not. It took me about 1.5 hours from start to finish and that included eating a quick dinner and putting my kids to bed. It probably took me 1 hour but I've been taking apart cars and putting them back together since I was 10. If you don't do much car work, I'd give it about 2 hours. If you have the rear cover and are trying to get to it without removing the manifold, good luck and allocate at least 4 hours for scraped up hands and dropped tools, filter and oil pressure sending unit. Not to mention aching stomach and chest from laying in the engine bay along with aching knees from leaning over into the engine bay.