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I had a dealer today tell me that the 2002 Z06 has oil burning problems just like the 2001. Is this true or does this guy just not know what he is talking about
 

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Not mine. Maybe some early 02's.
 

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I have seen a few posts of guys saying that their 02s or later models have also been consuming oil. I don't think oil consumption is that uncommon when the car is driven at high RPM for prolong periods of time. Even 01s typically don't consume oil unless they are driven in the 3500 t0 4000 RPM for prolonged sessions. Highway driving usually does not cause oil consmption in any model year.

Also, 01 Z06s are not the only cars where oil consumption has been reported. All manual shift LS1s and LS6s fall in the bulletin. This includes camaros, firebirds and vettes for model year 01 and before.


kileeman said:
I had a dealer today tell me that the 2002 Z06 has oil burning problems just like the 2001. Is this true or does this guy just not know what he is talking about
 

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Hi buddy,

There is a technical service bulletin that gm issued which includes the 2002 model for possible oil issues, however, the problem with the 2001 model was the piston rings as well as a problem with the engine valley cover. ALL 2001 models had rings with tensions which were too light. GM made changes to the rings for the 2002 + Z's. There were instances where the 2002 engine may experience excessive oil useage due to a faulty engine valley cover which caused oil to enter the combustion chamber. I owned a 2001 Z which used one quart every 400 miles. I had the re-ring performed and the burn rate went to 1/2 quart every 3K miles. I now own a 2002 Z and have had no oil burning issues. Hope this helps.

John
 

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When I first got my 02 I was startled when the DIC told me the oil was low. :eek2: I told the dealer that I was having to add a qt every 2000mi., he told me that GM allows 1.5qts every 3k mi. :screwy: I dont understand how they "allow" that much consumption. I dont drive the car hard at all, I guess im used to my 94 which burned NO oil. So now I guess I get to deal with it. :flaming:
 

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The oil consumption TSB does cover 02s, but that doesn't mean they all have the problem, just as all 01s don't have the problem.

I borrowed this off another thread:

1999-2002: Service Bulletin: Higher Than Expected Oil Consumption
Subject: Higher Than Expected Oil Consumption (Replace Rings and Engine Valley Cover)
Source: Chevrolet Dealer Technical Service Bulletin
Number: 01-06-01-023A

Models: 1999-2001 Chevrolet Camaro, 1999-2002 Chevrolet Corvette, 1999-2001 Pontiac Firebird, with 5.7L Engine (VINs G, S -- RPOs LS1, LS6)

This bulletin is being revised to add model years for the Corvette, information on the LS6 engine and parts information. Please discard Corporate Bulletin Number 01-06-01-023 (Section 6 - Engine).

Condition
Some owners may comment on higher than expected oil consumption. When checked, the oil consumption could be in the range of 400-600 miles per quart (700-1000 km/L).

On the LS6 engine only, the technician may find oil behind the engine throttle plate and in the intake manifold.

Cause
The cause for this condition may be an interaction between the piston rings and the cylinder bore in vehicles that are operated at higher RPMs -- typically manual transmission vehicles driven in a manner where the engine is frequently or consistently operating at greater than 3200 RPM.

On the LS6 engine only, the engine has a unique aluminum valley cover that has composite oil separating baffles and PCV plumbing incorporated. In some cases, the PCV baffle may not be properly sealed to the valley cover, causing oil to enter the PCV system.

Correction
On the LS6 engine only, replace the engine valley cover if oil is found behind the throttle body or in the intake manifold before replacing the piston ring. Refer to Engine Valley Cover Replacement in the Engine Mechanical - 5.7L subsection of the Corvette Service Manual.

A new set of piston rings is currently available through GMSPO. The new rings are part of a complete piston ring kit. Install only the number 2 compression ring and the oil expander ring from the piston ring kit. All other rings in the piston ring kit should be discarded. The original number 1 compression ring and the oil ring rails should be re-used in their original positions on the piston. All pistons should be used in the same cylinder bore.

Important
Do not dress or hone the cylinder bore. Nothing should be done to change the bore finish for this condition. Changing the bore finish may aggravate the condition.

Refer to the Unit Repair Manual for appropriate ring removal and replacement procedure.

The number 1 compression ring and the upper and lower oil expander rails are re-used because they are already broken in for the bore that they are in. The new number 2 compression ring is made with a very sharp edge that will break in quickly.

Changing only the piston rings noted, with no change in driving style, should change oil consumption to an acceptable level. Changes in driving style that reduce the amount of time spent at higher RPMs will also positively affect oil consumption.

In addition to the standard size piston ring kit listed below, a 0.25 mm oversized piston ring kit is available. The oversized piston ring kit should only be used in those rare instances where the cylinder bore size has been machined larger to accommodate the 0.25 mm oversized piston rings.

Parts Information

Part Number
Description
Qty

12568002
Valley Cover
1

88984247
Ring Kit, Piston
8

Warranty Information

For vehicles repaired under warranty, use:

Labor Operation
Description
Labor Time

J0250
Manifold or Gasket Intake - Replace Manifold
Use Published Labor Operation Time

J1307
Piston, Rod and/or Rings -- Replace, Both Banks
Use Published Labor Time
 

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I'm having the same problem.... READ the new Corvette mag (May 05)....it explains that all of the 99-02 Vettes (LS1 and LS6's) have this problem....(oil burning over 3200 rpm/ Cyl #2)

:mah: :cen:
 

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JKLNHDE said:
I own a very early 02 with a jan 02 build date. I drive it pretty normal and use around a qt every 3k miles.
My 2002 is much earlier than that ... built in early Aug 2001. Mine uses about a quart every 300 to 3500 miles if driven hard. When I was breaking it in (not pushing it hard for the first 1000 miles), it didn't use any oil. After break-in I started driving is much harder, and it will use some oil if pushed hard ... which is probably normal.

I haven't taken the intake hose off the intake manifold inlet to check for a bad valley tray (oil behind the throttle plate syndrome), but I would think that if the valley tray was bad that the engine would also use oil if driven mellow since the PVC system is sucking on the guts of the engine all the time.
 

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KevZ06Torch said:
I'm having the same problem.... READ the new Corvette mag (May 05)....it explains that all of the 99-02 Vettes (LS1 and LS6's) have this problem....(oil burning over 3200 rpm/ Cyl #2)

:mah: :cen:
So does GM say the 2002s have bad rings also? I thought it was the weak piston ring tension that was the cause of oil burning when over 3200 rpms. I think ALL 2002s had the updated rings (along with the coated piston skirts) ... so the only reason a 2002 and beyond LS6 might burn oil is because of a leaky valley tray (where the PVC system sucks from).
 

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I think ALL 2002s had the updated rings (along with the coated piston skirts) ... so the only reason a 2002 and beyond LS6 might burn oil is because of a leaky valley tray
That's correct. I would qualify that and say the only reason a 2002 and beyond LS6 might burn oil EXCESSIVELY is because of a leaky intake valley tray. Most LS6 engines will burn some oil, and that's normal. My '02 burns a quart every 3,500 miles, which is well within normal range for any engine. More than one quart every 1,000 miles is excessive, IMO.

Although I've owned some cars that don't use any oil, its not abnormal for an engine to use some. It's usually just variances in manufacturing tolerances.
 

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I'm probably in the minority here, but I think it's a mistake for GM to ship new cars with Mobil 1 installed. Over the years I've broken in a few motors, and dino oil works best for this, IMO. My prefered method is to run the car with correct weight dino oil for the first 800 miles, then change the oil/ filter, and then use Mobil 1 for the life of the car. Synthetic oils are just too slick for the engine to fully seat the rings, and provide a tight seal. Of course , this is mostly speculation, as you'd need to break in two identical motors using different methods, and then tear them down much later, with identical usage to quantify the difference. FWIW, I bought my car with 165 miles on it, and immediately changed to dino oil, like described above, and @ 7000+ miles on Mobil 1, it uses no oil between changes.
 
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