I know this has probably been beaten to death, but I noticed tonight when I stopped at Wally World, the dipper on my 6 banger showed she was half a quart low...guess it's time for my first oil change, and it's right around 3000 miles I've put on her since the initial purchase. My dad used to swear by Delo 400 15-40, and that's what I picked up. It says on the outside of the bottle "iso-syn", and is this a synthetic, or at least a semi syn? So I filled the crankcase, and I guess we'll see. Do these straight sixes normally consume oil like that all of a sudden? I know I have the famous Volvo "noisy lifter" syndrome at idle sometimes, will this shut that up? Sorry for the many questions, guys. Any thoughts?

Both the Delo and Rotella T 15-40 are popular for diesels. I suggest you check the API rating to be sure it's acceptable for "spark ignition" engines. Something like a SH- SJ classification. Diesels will have a "C" for "compression ignition" engines; Like CH-4 or similar.

1/2 Quart in 3,000 miles is not bad however if the engine was exposed to excessive short run driving then crankcase dilution may have kept the level up. A longer trip would create evaporation giving you the impression of increased oil consumption.

Unfortunately I know nothing about The inline six.

Thanks Rolyak,
I looked at the back of the bottle, and it says it is acceptable to use in gas engines, I figured since it is so hot here in TX, the sheer wieght of the oil would prevent vaporization. If anyone with info on the pecularities of the sixes happens to read this, any advice is VERY welcome!

I have (albeit temporarily) cured the noisy lifter at idle condition by giving the B6304 and "Italian Tune-up". They respond well to it, are quieter and smoother. Of all the oils I have tried in these engines, they seem to like the M1 5W40 the best. I know Amsoil makes a 5W40 that is very good but I have not yet tried it.

DEWFPO
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1998 S90 077,400 and 1995 964 154,100

I'd do an "Italian tune up", but I tend to get nervous at any RPM over 3-3500K because I took my old Honda w/250K in for inspection, and they ran it so hard, it slipped a couple teeth on the timing belt, and they bent a valve, which is why i ended up with the 960 in the first place. (my best friend put a new valve and belt on her, and he drives her everyday. I ended up just giving the car to him.) I let up as the tranny changes gears and baby the hell out of the Volvo, for fear of the same thing. Will these engines and trannys take those high RPM levels? Please advise. Thanks!

As long as the vehicle has been adequately maintained....scheduled timing belts, T-belt tensioner, reg. oil changes, and reg. atf changes, it will be fine. When I do mine, I just accelerate onto the freeway and leave it in second gear and run the rpms up to 4-4,500 rpm and let it sit there for about a minute or so and then I upshift the trans into drive. So it's not like downshifting the trans hard from 2K to 4.5K. It's a smooth run-up.

DEWFPO
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1998 S90 077,400 and 1995 964 154,100