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Discussion Starter #1
hey i guys i recently started to hear a knocking noise coming from my engine i can only hear it when i rev the engine or drive at about 2000-2500 rpm at idle it is not noticeable but i as soon as i put my foot on the throttle i start to hear it. i am going to try to post a video see if it helps really need help i am very concerned
https://youtu.be/2XbE5BSdbG0
 

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Punch it!
2008 AWD TBSS
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Don't run it anymore, sounds like its it's going to eat itself.
Save the block
 

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Discussion Starter #5
so what am i gonna have to change and is it going to be expensive i am on a very short budget and i am out of warranty
 

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TrailblazerSS
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so what am i gonna have to change and is it going to be expensive i am on a very short budget and i am out of warranty
Depends on who does the work. If you do it somewhere around 2000-3000$ if someone else does it 4500+
 

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TrailblazerSS
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That is way worse than mine and definitely sounds like bearings.

I'm on a budget and just pulled my motor myself if you need any tips. The ticket is knowing a motor guy or knowing how to do it yourself. Labor just to Remove and Replace the motor is $2500 around here (AWD) so I did that part myself.
 

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Discussion Starter #9
yeah man any tips i will take i have a buddy of mine that said he will take the engine out for free just get some drinks and food lol i talked to a shop to rebuild the engine stock it would be about 3500 so i asked them about how much the parts were and he said about 1200 so the rest is labor i was like hell no and he said that taking the engine out and putting it back in has the most time consuming and expensive part
 

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07 TrailblazerSS
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That's too bad, sorry to hear it! Definitely do something this time around about the oil starvation issue (like our pickup tube kit) so it doesn't happen again! Good luck with the repair and getting it back on the road.
 

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Discussion Starter #11
hey Kelly do you guys everthing that i would need there at pcm to rebuild my engine or any good places to shop for the parts??
 

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TT AWD TBSS Jeep
TT AWD SS Pwrd Jeep
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They can do just about everything there. Have em price a forged short block for ya. Some guys have got em as cheap as $2500 - or buy a forged eagle rotating assembly and have them throw it together. May or may not be cheaper, but at least youd know it was put together right. Top notch work done over there.
 

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It won't be cheap either way. Just need to decide what your budget is and go from there.

I have a good motor guy is the only reason I can afford it. I can do all the other labor unbolting and replacing stuff.
 

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Discussion Starter #15
Hey guys i went to a good friend of mine he restores all his cars builds his engines he drove the truck heard the knock and said i could get away with just changing out all of the bearings and check if the rod is bad and if it is replace if not keep is this true...he told me that i had to look into rebuilding the engine only if it was smoking or very low on power which at this point it is not
 

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Hey guys i went to a good friend of mine he restores all his cars builds his engines he drove the truck heard the knock and said i could get away with just changing out all of the bearings and check if the rod is bad and if it is replace if not keep is this true...he told me that i had to look into rebuilding the engine only if it was smoking or very low on power which at this point it is not
This usually isn't the case. I thought about this at first but you are most likely going to need a crank. This is a very common LS2 problem so there isn't much guessing involved...
 

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Discussion Starter #18
so i would be better off geting everything replaced ...i havent cut the filter the truck has just been sitting but its been raining and cant get anything done
 

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TT AWD TBSS Jeep
TT AWD SS Pwrd Jeep
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Usually when its knocking you cant just replace stock bearings, even if the .001 over ones chechout fine clearance wise. The reason is the scratches in the crank will eventually eat the new bearings up. I have done what your talking about before and polished the scratches our with 1000, 1500, 2000, 2500, 3000grit sand paper (due to finances) and its a band aid at best. It will usually still wear the bearings faster, one time it lasted about a year, another time almost two years. But its best to pull the crank and have it ground, polished, and if you have the coin balanced. Then just get the .010 over bearings and its as good as new. Just allot of time to R&R the motor and cleaning / building the motor. So yes you can probably fix the knock with bearings and cleaning uo crank as best as you can like stated above - but IMO just buy a forged Eagle rotating assembly and bolt it in. Measure the bores and if in spec, for just under $2000 you can have a rebuilt forged motor if you and your friend can DIY it.
 

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Discussion Starter #20
Aright guys well me and my buddy have to come to a decision and if the wheather gets nicer we are going to pull the engine out to inspect it and then i will be ordering the forged eagle rotating assembly...while im there any thing else you guys suggest i replace...i will keep you guys posted on the build
 
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