Do I have an oil burning problem?

[outrun]

Engine: GM 3800 Series II

Mileage: 134,000

OE Fill: 10W30 Conventional, ~4.5qts

Current oil: German Castrol 0W30

Miles on oil: 4,000

Oil topped off since oil change: 2qts!

A)When the vehicle was new and Mobil 1 5w30 and Mobil 1 10w30 was used consumption was around 1qt/3,000miles as a baseline.

What action should I take? AutoRX, dual cycles? used oil analysis? I do not think a switch to full 40 weight would help since GC is already a "heavy" 30 grade. Idle is much louder than usual ... compared to RP, or Amsoil ASL that is. The car was knocking few thousand miles ago ... or at least I thought it was after a cold start. I added 2 bottles of B12 Chemtool to 1/4 tank and burned it off. Problem has not occured since. My suspect thought was that if there is indeed burning combustion chamber fouling may exist. Then again cheap fuel was used. Since then only Texaco(with Techron), Formula Shell, and Mobil have been used. "Knock" if it indeed was has not returned.

Other than that, lower intake manifold was replaced 2years ago, and catalytic converter was replaced due to broken substrate last year.

There is no blue/white smoke coming out the exhaust

Any advice on how to proceed? Next change will try AutoRX with Chevron Delo400 followed by BG44K or Motorvac for upper engine cleaning.

 

[pgun67]

Is it leaking out the oil or just disappearing from regular driving? If it's a leak, then look for the source and attack from that angle. If it is burning the oil, then try the AutoRX as it can't hurt in my opinion. Two treatments. If that doesn't help, then come to conclude that it will use that and go for an inexpensive heavy weight. I would recommend a 15w40 as they are readily available and fairly cheap. I see Rotella 15w40 at Walmart all the time.

 

[Earl Filter]

The two 3800 Series IIs I've owned (a '97 and a '98 Bonneville, 95k and 103k) have used zero oil in 4,000 miles. Of course, I did have to change intake manifolds at each oil change interval.

I do hope you meant you changed the lower gaskets, and the upper intake itself.

 

[jamesn]

a quart to every 2K miles? not a big deal. in fact, a ford dealer would consider it within the normal usage. i bought a new contour in 97 and it drank oil like that from day 1. no help from ford. last ford i ever owned.