would 5w50 be too much

[HACCOFFICER]

I am using 10w40 syntec now, I have been reading some on the 5w50 syntec that is out now, would that be too thick for my 99 gm 3100 v6?


Before I get chewed out I use thicker oil, for 1 my engine loves it, and 2 I have piston slap and it helps, just so you know before you scream at me for not using 5w30

 

[Al]

I wouldn't go with 50wt or even 40 wt here in Pa.

I had Two 3.1's in Pa. Both thrived on 10w30. The '94 hammered quite a bit on startup, but went 100K when my daughter traded it in. RedLine is reported here by some to help on startup.

CG might b e a great choice.

I assume either you had the Leaking Manifold fixed?

 

[bighead]

I ran a couple of OCI's of GC, made the piston slap go bye bye (2004 Grand Am 3400 V6). It felt a tad sluggish with just a slightly thicker 30 wt. I cant begin to imagine the performance hit I'd get with a 40 wt, let alone a 50 wt!

 

[m2200b]

Shell rotella syn t 5-40 is about as much as I'd throw at that piston slap. I'd just try a mix of 15-40 delo and 5-20 Havoline or even 5-30 Havoline and see if moly is enough---- Havoline 10w40 for the nonmixer.

 

[bighead]

quote:

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Originally posted by m2200b:
Shell rotella syn t 5-40 is about as much as I'd throw at that piston slap. I'd just try a mix of 15-40 delo and 5-20 Havoline or even 5-30 Havoline and see if moly is enough---- Havoline 10w40 for the nonmixer.

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Funny you should mention the Havoline 5w30, because that's what's in the GA right now. I can't explain why, but, sometimes the piston slap is there, sometimes it's not. No relation at all to ambient temp, time of day, or how long the engine has been sitting (obviously, if it's only been sitting for a couple of hours or less, there won't be any slap because the oil hasn't *fully* drained yet). Seems like it depends more on which way the wind blows...

 

[Iain]

Redline 20W-50 will fix it for you!!

 

[oli]

quote:

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I have been reading some on the 5w50 syntec that is out now, [/QB]

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It's been out for at least 15 years.

 

[Buford T. Justice]

Ah... You should really be running 5w30 in that. 10w30 would be OK for summer. 0w30 would be an option as well.

 

[BlazerLT]

Since when does a 99 3100 need anything more than 10w30 in Penn State.

 

[dave1251]

Try to do an Auto-Rx clean/rinse this may help with your piston slap issues.

 

[KW]

Heck give it a try and see if you like it. It surely won't hurt anything.

 

[Russell]

Intersting. I currently have 5w50 Castrol Syntec in my 95 BMW 525i and have not noticed any change in performance or gas mileage from 0w40, 5w40 or 10w40.
Older BMWs seem to like heavy oil.

 

[HACCOFFICER]

quote:

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Originally posted by dave1251:
Try to do an Auto-Rx clean/rinse this may help with your piston slap issues.

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Done last month.

 

[HACCOFFICER]

quote:

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Originally posted by HACCOFFICER:

quote:

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Originally posted by dave1251:
Try to do an Auto-Rx clean/rinse this may help with your piston slap issues.

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Completed the rinse phase last month.

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[HACCOFFICER]

Use ARX already, didn't do a thing for the slap. Finished the rinse phase last month.


Anyhoo where do I get some of this GC you keep talking about? Does it come in the 5w50

 

[bighead]

GC is Castrol Syntec 0w-30. It's made in Germany, hence the name GC (German Castrol). Even though it's a 30 wt, it's on the thick end of the scale, almost a 40 wt (something like, 12.2 cSt or close to it). You can only get it at Autozone, but I personally have seen it at O'Reilly's Autoparts in the past. Anyway, when I ran it in my 3400 the piston slap was all but gone. Don't know if it was the thickness of the oil, or just the Uber add pack or what, but, it ran smooth as butter. Give it a try, of course YMMV...

Oh, and this oil isn't the GRP-III stuff either, GC is a "real" synthetic (not a bash on GRP-III synthetics, so don't try to go there...). Just an FYI...

 

[hominid7]

Unfortunatly, i'm not sure piston slap is going to be cured with a 5w50. In fact it may make things worse as it may be *too* thin at startup and make all kinds of noise, assuming your piston slap is most noticable at start-up.

I'd try a hearty conventional 10w30 like Havoline or Castrol GTX, and then step up to a 10w40 conventional if that does not work, or maybe even try a 15w40 if all else fails.

 

[Al]

quote:

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Originally posted by HACCOFFICER:
where do I get some of this GC you keep talking about? Does it come in the 5w50

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Sounds like he's locked onto a 5W-50..over and out..

 

[JohnBrowning]

No, It will work just fine. I do not know that it is going to work any better though then their 10W40. You might consider their 5W40. I know that AutoZone sell's their 5W40. The 5W40 and 5W50 can be run year round even dureing the winter months with no problems at all! You might consider useing a 15W40,15W50,20W50 dureing the spring,summer and part of fall then switch over to a 5W40 or 5W50 for winter use.

 

[HACCOFFICER]

Thanks for the advice. Still not sure on the 5w50, I will do some more research and make a decision. I like the 10w40 syntec i am running now. Its on the thin side of a 40wt, to I may thicken it up a hair. Thanks again guys