kevinr1247

A 944 Turbo that I recently purchased was serviced with synthetic 5W-40 synthetic (right before I purchased the car), about 700 miles ago. Don't know why they used 5W-40. The car checked out in a subsequent PPI with 140 across all cylinders and leak down numbers that were of no concern.

But, the other day when I cranked it up the oil light did not go out. So, I checked the oil and it was definitely low. I topped it up with 5W-40 synthetic. The car had had a major service right after I bought it...timing belt, oil leak repair, making be think that perhaps the oil hadn't been topped up after the service.

It's still early so I don't have a definitive gauge on how much it's burning, but I wanted to know if a 5W-40 would be more apt to burn away than say 20W-50. I don't know why it would, but I'm not sure. Thanks for the insight.

EDIT: 1989 104,000 miles, fully stock.

CyCloNe!

Well the 5w would be thinner so if there's any possibility of burn off it would be way more noticeable compared to the 20w-50. I always ran 15-40w or 20w-50 and can say I saw oil consumption still. How much were you down by ? Typically between oil changes of 4k miles roughly I lost about .5-1qt which in most vehicles is common especially since mine had 185k.

kevinr1247

I've been running it pretty hard so I know consumption is going to increase. So far I've put 3 quarts in it since the light came on. It's topped up now. I'll start keeping track a little better. But have to admit, I'm slightly worried.

But as I said, everything checked out on the PPI and I'm not seeing any obvious signs of burning oil.

konakat

Have you checked your coolant? That tends to be where missing oil runs off to.

Auto_Werks 3.6

3 quarts in 700 miles is very much too many. we're you seeing the light that literally says oil level low, or did the oil pressure light stay on? agreed on checking the coolant. if it's there you pretty much need to stop driving it until you get the oil filter console re sealed. i forget if you said you pulled the intercooler pipes to check for oil there, but a bad turbo can eat oil as well

kevinr1247

I'm going to keep better tabs on consumption. This is only now become apparent so I'll try to be more accurate in my assessment of how much oil is being used.

There is no evidence of oil in the coolant that I can see. It's nice a green.

The light that came on was oil level, not oil pressure.

There is what looks to be a light coating of oil on the intake air cowl, but that's all I can see from the visual inspection. I'll dig a little deeper.

odurandina

as a lifelong VAGina car owner,

i'm just not used to seeing such a bone-dry area of my car....

it's just weird..... "oh, that's the oil pan."

looking like a foreign object i just don't associate with an automobile.

looks more like an exhibit of NASA at the Kennedy Space Center.

Darryl H

Have you checked in the intake system? If you're driving it hard a lot the AOS system might be sending the oil up in to the inlet. I know on cars using over standard boost this can be quite common. Not sure it would be sending that much up though unless the seals were really knackered

svtlrtls

Hi, not to start an oil thread but to provide another experience story...

When I purchased my car (88, bone stock), the previous owner used Castrol 20w50 which I continued to use for another year or 2 and experienced about 2 litres of consumption over 5000km and oil smoke on start up. I, like the OP, was concerned.

A few years ago, I switched to Rotella T6 5w40 and ran a can of liquimoly sludge remover at the time of the switch. Since then, I use slightly less oil (about 1.5 litres) and noticeably less smoke on start up.

I switched to 5w40 because I live in eastern Canada and I wanted an oil that would flow better on cold start ups.

I can't say why the consumption is less or why there is less smoke but I can say I sleep better at night. Yes, I'm delusional about my oil "analysis" but there you go.

Cheers

kevinr1247

Thanks for that. I'm in the process of dialing in exactly how much consumption per mileage. There are some unknown variables at this point, mainly, I'm not sure how much oil was put in the car when it was serviced prior to purchase. It may have not been filled completely, so I may be over estimating consumption a bit. Also there may have been some leakage during the service/maintenance that I had done...timing belt, oil seals. And they did find some leaks that they fortunately were able to get to fairly easily. I doubt the mechanic topped the car up after.

This car doesn't smoke at all on startup, nor when I'm running it hard, as far as I can tell. I'm hoping that what I observe will fall into the "normal" consumption category.

I was wondering if 5W was more likely to burn off faster than 20W. Sounds like that might be a possibility, but perhaps not.

CliveB

I filled up with Mobil 1 0-40 once and it disappeared in no time at all.
I now stick with the factory and Shell recommeded 20/50 and use a lot less.
From the Shell listings at the time all Porsche cars used thin stuff apart from the Turbo Models. (911, 924 and 944).
My '86 does not have an oil level light. Was this a later improvement?

kevinr1247

Not sure on the '86. The '89 does have an indicator on the left instrument cluster.

Auto_Werks 3.6

they added it in 87.

kevinr1247

So quick question. I'm running the 5W-40 Rotella as I think I mentioned. It was what the PO used for a recent service (cold climate).

When I start the car and let it warm up, no revving, it burns a little oil for about 1-2 minutes then clears out. I can see it. Then it clears.

Compression/leakdown numbers were good as I mentioned. 140s and less than 10%. 105k miles.

What am I looking at? Valve seals, turbo or both? Thin oil? Thanks.

mrgreenjeans

Also at the risk of starting another oil war thread, let me relay my experiences.

I currently own around 8 - 944 Normals, a Carrera, a 914, and an '89 - M030 / 951 like your car.
Most are under 70,000 miles and are all well taken care of vehicles scrupulously maintained by either me since new, or the previous owners since new. The 951 has around 55,000. ALL have been on a diet of Mobil One Synthetic 15/50 or 20/50 since new with ZERO oil issues on either oil leaking past seals or from blowby on the valve seals or rings.

I am sold on both the quality of the Mobil One motor oil and recommend it, especially on any track used vehicles such as several of mine are.

I may also add that none of these cars are cold weather driven in winter usage, nor have they been in their previous owner's usage, but I do know from many others I associate with at the track or at PCA functions, similar verifications on satisfied use is heard. Even during a winter regimen where a lighter viscosity is used.

There are no quick start ups and go, especially on cool mornings, on any of my cars. I allow a few moments of warm-up time, especially if there is going to be any full throttle application.

The light oil misting in the airbox is more common in some than in others. But, it's presence does nothing to concern me about any oil usage in my vehicles, nor does it bear record of 'consumption'.

By the way, according to our owner's manuals, consumption is considered acceptable to within 1 qt. per 6-700 miles before concern for rebuild by Porsche standards. And if you do your services at the dealership, they will more than likely be putting in 0/40 Mobil One..... something more to chew on.

Any idea when seals or turbo have been replaced in yours , if ever ?

( as an aside, what year and color is your Carrera ? Mine is an '88 in Venetian Blue, and "un-spoiled". )