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Discussion Starter #1
Well, after 14100 miles my 2013 427 Corvette, it is now getting a new LS7 crate motor direct from Chevrolet. The diagnosis is same as my buddy's 2013 with 9000 miles. It appears there is a coating on the rods that can slough off and contaminate the complete oil system, thus wearing all components. The symptoms are hard starting on a hot motor and low oil pressure at idle <20psi.

Glad I purchased the aftermarket warranty from GMC, all covered :D

Thanks to Able Chevrolet in Rio Vista, CA for all of their expertise and assistance in taking care of this problem.
 

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2011 was the last year for Tri metal lead based Main & connecting rod bearings used by GM.


Come 2012 to present they are Aluminum Main, Connecting Rod & Cam bearings.


So your old 2013 & GM replacement LS7 has the same aluminum engine bearings.


The Ti rods chromium nitrate coating wears gradual.
Its the coating GM used there are others out there.
Ti wear dust gets embedded in Lead Based engine bearings so no harm done.


Aluminum bearings do not trap or embed any foreign debris period.
So the engine wears out fast and just self destructs.


Sole reason why earlier Ti rod engines lasted over 100,000 miles ran hard they had Lead based Tri metal bearings.


GM Took the Lead out so Kaboom it blows up.


All You can do is use a Premium True racing oil & I would use a thicker spec.


Do Your homework.
 

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I have a 2009 C6 Z06 Ti Rod & piston.
Customer gave it to me after a Factory Mahle piston failed.


Rod looks like new has zero side check big end wear & it has a Lead tri metal rod bearing in it yet.


When the Mahle piston failed it took out the aluminum block.


Let go at 150,000 miles and he had over 900 HP at rear wheels supercharged.
He was street racing at 170 mph when it let go.
 

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The Real solution is to install Cleavite Tri metal bearings.
Lead based bearings.


Never going to do it with a GM Dealership & Under warranty.


Cluster fick....It will blow up again with aluminum engine bearings & the LS7 Ti Rods.
 

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Discussion Starter #5
Some good information and not so good news about my new motor. I really do not need to keep swapping motors every 15 thousand miles, even if they are free. I am going to take a look at all my options here.

Thanks Guys
 

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Some good information and not so good news about my new motor. I really do not need to keep swapping motors every 15 thousand miles, even if they are free. I am going to take a look at all my options here.

Thanks Guys
You could get the Warrenty LS7.
Take it home and go through it and install your engine bearings from Cleavite.
Tri Metal Lead or otherwise known as Babbit overlay bearings.
Do it yourself. Or get help from a good mechanic like me.
2 k to do all fair for a real mechanic working on the side.
 

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Discussion Starter #7
You could get the Warrenty LS7.
Take it home and go through it and install your engine bearings from Cleavite.
Tri Metal Lead or otherwise known as Babbit overlay bearings.
Do it yourself. Or get help from a good mechanic like me.
2 k to do all fair for a real mechanic working on the side.
I have an extended warranty until middle of next year. New Engine warrant is 3yr 100k. if i change internal components wont it void my existing warranty?
 

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I have an extended warranty until middle of next year. New Engine warrant is 3yr 100k. if i change internal components wont it void my existing warranty?
Most gave up on LS7 I read.
Sold them off.
Or bought Callies Rotating assemblies and used an iron truck block with LS3 Heads.
Steel rods used instead of Ti.
 

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The Entire ideal behind Titanium rods in the LS7 was to use Mobil 1 oil 5w30 with a 7000 Rpm redline.
They Tried with Forged Steel rods to begin with and had engine failures because of too high of reciprocating mass claimed.
The real issue was 5w30 oil.....too thin when hot its like water with little film strength.
That was then.
Racing oils are better today.
Royal Purple XPR is best you can buy and it's not cheep at $20 per quart.

10w30 would have been a better choice.
Drag Racers used 20w50 for a reason and still do today.

5w30 gives max fuel economy.
 

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Couple of photos I also posted on Grump's site tonight also.


The C6 ZO6 piston & rod the customer gave me.
He had 1000 RWHP and It let go with a Big Bang.
Rods all survived.
Factory Cast Hyperuentic pistons failed.
Amazing strong rods Titanium.
The Larger Rod is my TA Pontiac Crower Titanium rods I am using my engine build 2019.


The bearing is Lead Babbit. Scratched easy with my thumb nail.
On backside of the rod bearing its stamped 07/07 for July 2007 made.
No Titanium dusting issue like later aluminum bearing LS Engines all. They even used aluminum bearings in Crate Big Block Chevies all. Grumpy showed us recent.
Terrible for High HP & Racing...they Suck....going to go Kaboom with HP !
 
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