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Posted

All - been a while but wanted to check in. 
 

i have a 17 1500 5.3 with 220k. Oil changed every 3/5/7000 miles. Owned it since new. 
 

dod was tuned out at 75k and motor was out at 145k due to collapsed lifter. Bottom end was left alone - new cam / lifters / dod delete. 
 

I started running 5w30 from 75k to 195k. 
 

To the main issue - around 190k, it started to burn oil.  Currently it’s around a quart per 500 / 600 miles or so. Over the last 6000 oil change - I added 11 quarts lol. 
 

I tired Valvoline restore and protect for 20k miles at 3k intervals with little change. Installed a catch can at 217k and only catch about 3 oz over 3000 miles. 
 

I’ve been running 10w30 for the last 6000 miles. Just did an oil change and stuck with 10w30. 
 

I’ve ordered replacement valve covers.  It seems the numbers have been updated multiple times and the covers are the same as the next version of 5.3/6.2s. 

I’ve only installed the drivers side so far but I wanted to show you my old

cover vs new. Not much difference but it seems the old cover was bypassing the baffles and sucking oil / vapors right into the airbox. 
 

it seems GM changed some of the rivets in the middle of the baffle to maybe hold more pressure on the edges against the cover.  I’m going to drill the rivets so we can see what’s under the baffles. 
 

has anyone dealt with this much oil consumption / valve covers / updated part numbers?

 

thanks all. Really hoping this engine makes it to 400k without touching it again. 

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Posted

Here’s one more of the new drivers side cover. 
 

will upload pics of the passenger side when I swap them over. 
 

also here’s my passenger side cover when the lifter collapsed at 145k in November of 2022. 
 

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Posted

Have you looked at your brake vacuum pump?

 

 On the 2017 Chevy 5.3L, a failing mechanical brake vacuum pump can cause excess oil consumption. The pump relies on engine oil for lubrication and a seal. If internal seals fail, the pump will draw oil directly out of the crankcase and push it into the brake booster or intake, where it is burned.Key Symptoms of a Failing Vacuum Pump. Hard or stiff brake pedal: Loss of vacuum assist makes braking effort significantly harder.Oil in the vacuum line: Disconnecting the vacuum line to the brake booster will reveal wet oil inside the hose.Noisy operation: A clicking, grinding, or loud tapping sound coming from the front/driver's side of the engine.Smoke from the tailpipe: Burning oil as it cycles through the intake.

  • Like 1
Posted

I just deleted the vac pump but there was no oil in the line to the booster and brakes always felt great. Wanted to remove it from the equation before it was an issue.  I installed the two plugs in the oil passages and a block off plate. 
 

there’s a company that makes a vac manifold that goes between the purge valve and the intake. I used that for the booster vac line - I didn’t want to T into my catch can return line. 
 

the vac pump was replaced under warranty back in 2019 or so, so it was the new style pump. 
 

  • Like 1
Posted

I don’t care if it stops burning oil. I just need to slow it down.  It’s got 220k. I never missed an oil change. It doesn’t make sense for the oil rings to not do their job - the plugs aren’t caked and my factory cats are still in place and functioning.  
 

I don’t think there’s excessive crankcase pressure from worn compression rings because I don’t get a lot of oil in my catch can between the PCV valve and the intake. 
 

I tore apart the old driver side VC. There’s a sealant between the alum valve cover and steel baffle assembly that’s riveted down.  It seems the seal let go near the port that goes to the intake / before the throttle body. 
 

The design looks like a sealed side that sucks from the air intake and pulls from 3 / 6 holes and then internal baffles seperate the oil / vapors from the air and then drain back down and drip to the heads. 
 

Once that seal fails, oil will be sucked up right into the air intake / before the throttle body. It won’t pass through the separators and you’ll burn more oil. Add in the fact that both valve covers could attribute to this and you may end up with significant consumption, especially when you add in the amount of miles. 
 

I do not have a brand new valve cover to tear apart to see what they changed inside the cover. Part of me wants to waste the $75 but that’s 6 quarts of oil if these fixes don’t work lol. 
 

see pics of drivers side cover pulled apart. 
 


 

 

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  • Thanks 1
Posted

Did the passenger side today. Seemed worse than the drivers side. I’ll check back in 5000 miles or when the low oil light comes on - whichever comes first. 
 

on another note - went to do sway bar bushings and 3 of 4 bolts broke. Gotta love New England. 
 

 

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  • Like 3
  • 4 weeks later...
Posted

I'm at 315k miles on my L83, dod/afm still operable. It "uses" about 1.5-2qts per 5k miles. I use Valvoline 5w30. I top it off at 2,500 miles between changes I had to replace the valve cover gaskets a while back, the passenger side was leaking and soaked the starter. 

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