mellis

I have a new (to me) 96 A4Q with 52,000 miles. I would like to move to Mobil1 but I am receiving conflicting advise as to the correct viscosity for the 12V engine. Any advise appreciated. FYI, I am in Maine so the summers are not TOO hot!

Mark

Reggie3

They produce less deposits. Studies they ran (independent of the oil companies) showed that the 20-50 wts would leave more deposits on the cylinder heads and valves. Also the lighter wt oils would give you better gas mileage.

Since you may not know the history of the car you may want to put in conventional oils for 1 or 2K with a detergent additive - then go to Mobil 1. This will clean the engine of any deposits. Chevron makes a good one.

Being in Maine you may want to use the 0-30 for the winter.

I am going to Mobil 1 (5-30) this month on mine for here in Colorado. Since we do not have a turbo the need for Mobil 1 is diminished if you change your oil often (I do mine every 2.5k miles) so I have been running conventional oils on my cars).

Reggie

98.5 2.8 QMS

BTW - you will get quite a range of opinions here on what to do - I think if anything you pick up you should change the oil often

WClark

This may sound strange but I can feel the difference oil makes in my daily driver. I presently drive a '96 Legacy Outback / 2.2L (2001 A4 on order). When newer 5W30 synthetic felt better than 10W30. Now it is above 50K miles and the 10W30 weight feels better.

The feel is in the form of tactile (thru the steering wheel, shifter and seat) and audible feedback. When right the engine feels smoother, quieter and stronger. I have been able to pick up on this since my first 4 banger, a '73 Fiat 124 Spyder. Thus far cars I dont drive a lot and those with V8 engines dont register the same way.

This feel also "tells" me when the oil additives have depleted or base oil needs to be changed. For instance Syntec needs to go at about 4k miles and Mobil1 at about 7k in my Outback. With synthetic oils I feel very little difference between warm and cold weather performance.

So where is this leading? In my opinion each engine has an ideal oil viscosity and it may not be what the next guy likes. I would start with 10w30 then at the next change try 5W30 of the same brand and see if one seems better than the other. You might even go further at some point like to 0W or 15W but my guess is both are outside what your engine works best with.

The advice of allowing a cleaning cycle to remove old deposits is a good one. An engine that has run non-synthetic may have a lot of contamination buildup that the higher detergent synthetic will wash away, really fouling up your first change. A good way to handle this is to run with 1 quart of the synthetic in place of 1 quart of the regular oil for a couple thousand miles, then switch to all synthetic and a premium filter.

QCRAZY

... 5W30 or 10W30 at first(not a lot of difference between the two). You could run the 5W30 in the winter and the 10W30 in the spring thru fall for starters.

If you start getting lifter "tap" with the thinner, --W30 oils, I would then switch to a 10W50 oil(or abouts)!! The thicker oil seems to clear up lifter "tap" better than the thinner oils!!!

Good Luck
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Andrew