Hi, I have fitted a secondhand LS6 into a Cobra replica. It's got great performance and is very smooth. Only problem is the oil (mobil 1) consumption. What I can't work out, is that there are no leaks and no obvious signs of it coming out the exhaust. It sailed through the emission tests. Any ideas??

 

PCV system may be letting oil through the intake. Or worn piston rings or worn valve seals.

 

Is the motor an '01?

 

PaulFLS6,
brad8266 has brought up the most obvious things. If you have the LS6 engine, I assume that your PVC system draws vapour through the valley cover (front right corner). This is the best for minimal oil consumption.

Try replacing your PCV valve for starters. They're inexpensive and if it is sticking in the open position, this could be the culprit. Next, I'd try replacing the valve seals as this can be done without removing the heads.

I have some questions for you.

1. Are the heads stock or have they been ported? If they have been ported, the rocker arm bolts or studs need some sealant on the threads.
2. Do you know how many miles/kilometers are on the engine?
3. How much oil is it using per thousand miles/km?

Thanks,

Steve

 

Most has been covered. LS6 PCV mod. Catch can. Oil/Air Seperator.

Also, try GC 0w30 oil, its a little thicker than M1. Or perhaps the Amsoil Euro 5w40. Both are excellent oils to run in these cars.

 

I am not running with the PCV system. I just blanked it off. I think that the motor is from 2002/2003. Were there problems with the 2001 motors?

Does the LS6 usually have a high thirst for oil?

 

Some are known for drinking oil...

 

This engine series is known to have some oil consumption problems although some engines use very little. You need to have some kind of crankcase ventilation. Either a "breather" of some type that vents oil vapours to the atmosphere or a positive crankcase ventilation system that vents to the intake manifold. Otherwise, over time you will blow seals due to the inevitable combustion blow-by that goes into the crankcase and must be vented somewhere/somehow.

Steve

 

Where's the best place to vent the engine from?

 

right from the valve covers actully. most including me run a big breather on the pass side oil filler and a small one on the rear driver's side

it is a common issue with the lsx motors and some cars will need this type of setup and some can get by with a catch can setup
also what mobil one are you using? 0w40 seems to work the best as far as mobil one goes

 

right from the val covers actully. most including me run a big breather on the pass side oil filler and a small one on the rear driver's side

it is a common issue with the lsx motors and some cars will need this type of setup and some can get by with a catch can setup
also what mobil one are you using? 0w40 seems to work the best as far as mobil one goes

 

Using 0-40 Oil. Thanks for all the responses.