synthetic when burning 1 quart every 2K?

[db500]

I have a volvo S70 non turbo with 285K on it. I have been using Pennzoil conventional for 7K runs which are all highway miles(UOA supported it) and in the last 30K I have switched to synthetic and 10K runs (Mobil 1 High Mileage or platinum).

I have done the Auto-rx thing with no change in oil consumption and am burning 1 quart every 2K pretty steady.

I'm interested in keeping with 10K OCI's going forward. Given how much I am burning, I wonder if it would be ok to just use dino since it is getting turned over once in 10K (5 new quarts).

 

[UNC017]

Some may have a clearer view, but for me its a tough call. Yes, you're adding fresh additives every 2k miles, but an engine that burns oil also contaminates its oil with fuel, water, and soot much faster, further stressing the additives that are there.

I'd probably go synthetic if it were my car, or else stick to shorter OCIs.

Or you could do a periodic oil analysis on a run up to 10k with conventional oil and see how the TBN and other numbers hold up. FWIW, I would sample right before adding a quart to get a "worst case" measure.

 

[1999nick]

Were it mine, I would be tickled to death having oil consumption of one quart in 2000 miles with 285,000 miles on my engine. You don't say what weight oil you are using. I would try some brand of 5W40, or maybe Mobil 1 High Mileage 10w40 oil. I just finished a 9117 mile run using Mobil 1 10W30 High Mileage oil, and my vehicle only used about one third of a quart. It was a one year OCI.

 

[jonny-b]

If you have been using conventional oil all the time in this engine, it could be an idea to just use synthetic, to see if the oil usage will drop.
This is of course if you use "true" synthetic(group 4 or higher), not the group 3, that most oil companies in the US call synthetic.

If you are not using true synthetic, I would just use the YB and add one quart of MMO or Rislone, when you do an oil change.

Hopefully, this can give better results than ARX.

If your valve guides are worn, it will continue to use oil, though.

 

[ryan2022]

hmm, I would probably go for it, I'd just go with a heavier weight possibly high mileage synthetic.

 

[ThirdeYe]

Hi,

My girlfriend's 1999 Grand Am burns 1 quart every 1,500-2,000 miles like clockwork since we bought it. She drives it very easy as well and takes good care of the car (she's a keeper

) but anyways, I wouldn't bother with a synthetic in it if it is burning oil at that rate. I've been using conventional Valvoline 5w30 in hers changed every 3,000-4,000 miles because that way I don't have to keep topping it off. I just add a quart at the 1,500-2,000 mark and have her run it until it gets to the add mark and change it. However, for her next oil change I am going to try using Valvoline MaxLife Synthetic Blend to see if it helps curbs the consumption. I've used it in leaking applications with good results but I haven't tried it in a car that burns oil. I've been told by other users here with the same car/engine that it can help. I know it's not a Volvo, but it's worth a try. I would use MaxLife Full Synthetic or Mobil 1 High Mileage if you can find it, or if you can't, try Pennzoil High Mileage, Castrol GTX High Mileage or Valvoline MaxLife Synthetic Blend.

Good luck!

 

[MrWideTires]

1 quart for every 2000 miles is not that bad.. that's usually what STIs burn, specially if you drive them really hard

 

[Gary Allan]

You're exchanging the entire sump over the course of your proposed OCI and you've got a consumption rate that appears linear. This isn't an oil fatigue issue or transitional one. It's a static mechanical/design issue, perhaps due to your sustained highway usage (or so I would reason).

I didn't see that you've altered visc up a tick to see if it effects the consumption rate.

This is a curious situation. First I'd get some Rotella T Synthetic 5w40 to see if visc alters the consumption. Beyond that, I'd use your conventional oil of choice in the specified weight for the full 10k and do a used oil analysis. Then you'll know if you're in some perpetual free fall of consumption/replacement in terms of oil condition. It would take much longer to get a fully mature sump, but it will tell you if 10k is too short. You'll see if consumption increases over the 10k span ..which would point to oil fatigue. Either way, it's unlikely that you'll approach any level of risk/damage/whatever in this scenario.

Oil filters should have a long life in this service. The bulk of the mileage is hollow with hardly any fuel enrichment miles.

Can we figure that you've ruled out all the usual suspects on the origin of this consumption?

 

[db500]

yeah, I've done the whole oil separator system in the last 30K miles (plus the RMS). Other than two doses of Auto-RX not sure what else I can do.

I've always run YB10w30 in the summer and winter (upstate ny). I have Mobil 1 High Mileage 10w30 in there now and will do a run of Mobil 1 High Mileage 10w40 next since I have it already.

I was thinking of running Rotella 15w40 in the summer going forward and see what that does.

Maybe I'm a prime candidate for that lucas oil treatment stuff? I've never been a big fan of that type of additive though.