15w40 for 99 vortec 350 4x4?

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Is there anything special with vortec heads/systems that I should stay away from 15w40? Truck has 150k on it.

This is my first vortec motor, so I'd rather not do something silly right off the bat.
 
Bad intake manifold gaskets, failed CFI injector (spider), or worn out distributor will stop your all iron 350 long before an oil choice will. There's very few bad choices thicker than 5w30 in a Small Block Chevrolet. Provided you keep the coolant out of the lip and don't fuel wash it when the injection acts up it will live a long life on Super Tech 5w30, 10W30, 10w40, 15w40, or 20w50.

15w40 in my opinion is a great oil for any generation SBC, Vortec included.
 
For the most part, I've read here that they don't care for thick 40 weights.

5w30 or 10w30 is all they need. I'd entertain 0w40 as well.
 
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Originally Posted by dlundblad
For the most part, I've read here that they don't care for thick 40 weights.

5w30 or 10w30 is all they need. I'd entertain 0w40 as well.


Why entertain a 0W40 when it says 5w30 on cap? Maybe entertain 0w30
 
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Originally Posted by leroyd92
Is there anything special with vortec heads/systems that I should stay away from 15w40? Truck has 150k on it.

This is my first vortec motor, so I'd rather not do something silly right off the bat.



If you have the 15W40 on hand go ahead and use it.
 
Anything from 0w-30 to 15w-40 will work fine, but I'd stick with a 30-weight if you don't have any consumption or leaking issues. I've owned many SBCs.
 
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Originally Posted by daman
You don't need anything that thick! my '99 with 235,000 lived on 0w30.



15W40 isn't thick and it won't hurt a thing in Arizona.
 
FlyNavyP3, do you think 15W40 is good for even the 4.8 and 5.3 Vortecs? Considering it in a 4.8 Vortec with VVT with 180k miles and just letting the OLM hit 0% from here on out.
 
Originally Posted by mobilaltima
FlyNavyP3, do you think 15W40 is good for even the 4.8 and 5.3 Vortecs? Considering it in a 4.8 Vortec with VVT with 180k miles and just letting the OLM hit 0% from here on out.



It will work fine because the engine isn't picky not so much the oil.
 
Originally Posted by mobilaltima
FlyNavyP3, do you think 15W40 is good for even the 4.8 and 5.3 Vortecs? Considering it in a 4.8 Vortec with VVT with 180k miles and just letting the OLM hit 0% from here on out.

I'd just use a syn like Mobil 1 10w-30HM or 0w-40 in LA, especially if you can get it on a rebate like Mobil 1 if you want to do longer drains. If you can get the 15w-40 for cheap though, it will work fine too.
 
I suppose it depends on your climate and how you use it.

My 1995 K3500 7.4 liter has 300,000 miles on whatever cheap 15W-40 I could buy.

YMMV, though.
 
Originally Posted by daman
You don't need anything that thick! my '99 with 235,000 lived on 0w30.


It's really NOT any thicker than 10W-40 (and he's in Arizona, so.....)

It'll run forever on that oil.
 
Every generation of Chevy V8 has been fed 15w40 in fleet service. The engine doesn't care.

In marine service, millions of them are fed nothing but 25w40 and 15w40. The engine doesn't care.

Some of our NPRs go around all day at 2500-4000 rpm (5.xx axle ratios) with Vortec engines and 15w40. The engines don't care.

There is nothing to fear from dumping 15w40 into a Vortec, and the engine isn't going to suffer any compromise.
 
Originally Posted by mobilaltima
FlyNavyP3, do you think 15W40 is good for even the 4.8 and 5.3 Vortecs? Considering it in a 4.8 Vortec with VVT with 180k miles and just letting the OLM hit 0% from here on out.


No reason why you couldn't, it's my go to for performance LS builds that don't quite need a race oil but want more than a PCMO has to offer. Generally for daily driver duty with an engine with a roller cam and roller valve train (read LS) I'm comfortable with a PCMO. The traditional SBC with a flat tappet cam and non roller valve train my entering argument is 15w40 without API SN, not required for roller cams. HDEO does an amazing job keeping engines clean, even in a conventional, the add pack is robust, what's not to love? The add pack and cleanliness of engines I've torn down make me lean towards HDEO in everything suited for it, which in my case is nearly everything I own. The GS 350 Lexus that the other half drives will continue to get PCMO, but I'd run 15w40 in it too without fear, but then where would I use my clearance M1 AP 5w20 lol.
 
Ive used 15w-50 in Vortec headed SBC. Worked fine. In fact GM recommended it. GM crate engine.
 
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