What Syn oil do you all use and what wt
 

what Wt of oil do you all use and what brand do you use.
here where im at in MO its been hot. over 100 often the past few weeks.
when I got my car I changed the oil on it pretty quick since it had a jiffy lube sticker in it:eek2:
because of the heat I put 10w30 Royal Purple in it.
has ran fine but wanted to get your alls opinion on it.

It's gonna vary based on the build. With that said i run VR1 20w50

mine is all stock motor

I use pennzoil platinum 10w-30

I like M1 0w40 for (stock short block) LS1 applications.

Amsoil Signature Series 5W-30 Synthetic Motor Oil (ASLQT-EA)

Retails for $12.05 a quart.

New crate LS3 - M1 5w-30 as suggested by the builder. However, once we've got a few more miles on it, I'll likely give M1 0w-20 a try and see what impact on temps and pressures occur.

Joe Gibbs LS30 is all I run in my WS6. It's a 5w30 oil.

Rotella t6. 5w40

Mobil 1 Synthetic 5w30. Car runs great

1999 daily driver Z28, stock LS1 206k Valvoline Syn 5W-30, runs great

2002 SS garage queen 10k miles gets whatever GM dealer puts in it, I would assume its Mobil 1 5W-30

Mine and friends' experience with dealers over the decades - they charge you for Mobil1, and who knows what they actually put in. Daughter just had a dealer oil change in her car, and there's a good amount of evidence that the hood was never opened....sad.

Sorry for derail - not a lot of dealer love.

Currently M1 0w-40 (pre-2016 strength).

The current M1 0w-40 is called "FS"...and is somewhat lower viscosity and HTHS at 100 deg C. The newer M1 0w-40 has lost the mfg certs from BMW (LL-01) and Nissan. Not sure if I will go with FS next time around or go back to a stouter 30 grade (0w-30, 5w-30, 10w-30). Mine is 100% stock and I don't drive it all that hard. So an oil with 11.0-12.0 viscosity and HTHS of 3.5 should be more than enough protection.

M1's stout 30 grades are the 10w-30 High Mileage, and 0/5w-30 ESP. I might consider the HM next time, though I'm not a fan of extra seal swellers when you have no leaks. And the reduced detergents in the ESP I have to wonder about. I like the extra Zinc you usually get in a 30HM or 40 grade oil. The M1 0w-40 is loaded with Ca/Zn/Phos/Moly/Boron. Very high TBN too. It's only draw back might be the high % ash it leave behind and the little bit more of Cat loading from the heftier add package.

For now I want to stick with the non-Magnesium and non-Sodium motor oils. That leaves out all the 30 grade Valvoline and 30 grade Mobil 1 oils. Most of the European certified 40 grade oils out there are high Ca/high Zn/high Phos blends. Even Valvoline when jumping to the their stout 0/5w-40 MST oils leaves the sodium out to employ a high calcium oil. To make the decision harder, the fully Euro mfg certed Castrol Edge 0w-40 is a magnesium oil (it didn't used to be), while their 30 grades are not. Rotella T5/T6 5/10/15-40 grades are just fine in a hot weather climate and with a very stout add pack.

Since it sounds like the OP is in a hotter weather climate I'd recommend a strong 30 grade or one of the lighter 0/5w-40's synthetics (PP/M1/Castrol Edge,Valvoline MST). At a minimum in a hot summer climate I think you should do fine with a quality 10w-30 which reduces the shearing potential. Not a fan of Royal Purple, especially at the higher cost (show me a mfg cert approval). I do my own oil changes and they cost me under $20 for oil and filter. I get my Mobil 1 from Walmart at $22.88 and use the $12 M1 rebates that come out 2X per year ($10.88 net for a jug). I use the Fram Ultra Guard synthetic filters ($6-8) depending on source. I only put 1200 miles on per year so an annual oil change, with a filter change every 2 years (the Fram Ultra is recommended up to 15,000 miles). I could probably go a lot longer on both oil and filter.

Mobil 1 5w-30...

Mobile 1 . 5W30

Mobil 1 5w30. Walmart or BJ's run sales.

Tried them all. car has 167,000 and use to drink a quart every 3,000 miles. Light tapping/slap when engine was cold. I have used Mobile 1 0-40W European car Formula and the last 30-40k miles it loves it! The car doesn't drink any oil and oil measurements are under a table spoon or shot glass amount and 99% of engine noise it gone. I use 0-30W in winter. My car had problems starting when it's under 5 degree's in CT winter and changed out 10-30W that the previous owner used and used lighter oil and starts in negative weather conditions. Some reason LS1 engines don't like heavy oil in Alaska like conditions.

Not much difference using a 0w-30 vs. M1 0w-40 Euro FS...especially in CT winters. Both are essentially the same viscosity at the high and low ends since Mobil dropped the 0w-40 spec from 13.8 cSt at 100degC to 12.9. Most decent 0w-30's are in the mid-12's. Add packs are quite different though with the M1 20/30 grades being low calcium, high magnesium...while the 0w-40 is high calcium, no magnesium. A 5w should be fine down to about -20 degF and a 10w fine to around 0 to 10 deg F.

Good LS1 oil deals going down at Adv Auto Parts as they clear out their supplies of Quaker State oil for good. So many stores are selling the QSUD and synblends for $6.95-$8.95 for5 qt jug. Toss in the $5/$7 rebates (max of $21 per person) and you can get 3 jugs of QSUD for a net of 39c/qt. For those that say you can't find cheap, quality oils, here's a chance to stock up. I picked up 18 quarts for my 2 cars. I'd no qualms running 5w-30 QSUD (or 10w-30 in summer) in my 1999 SS if M1 0w-40 ever disappears.

I see you're from CT. You having trouble finding 10-40W Mobil 1 , 0-40W, or 0-30W at parts stores or Walmart in CT like me? I tried Quaker and my truck and Camaro don't like it. It seems too watery and my LS1 was consuming about 1 Qt every 3,000 miles if pushed hard. Truck would pi$$ out any Quaker weight oil even thick oil but is fine with Mobil 10-40W but it's a K1500 Z71 with 300,00 original miles on the 350 tbi for plowing and towing. It's amazing how even different brands with the same weights react differently from 6-10 oils I experimented with the LS1.

I run Pennzoil Platinum Synthetic 5W-30! It gets really hot here in California too! Haven't had any problems so far. My car has basic bolt ons so it is pretty close to stock