LT1 and LT4 Engine Oil - Summarized
 

There's a lot of discussion here and on many other sites about ZL1 oils, but the topic looks simple.

Chevy's High Performance Owner's manual Supplement states:

The LT1 and LT4 engines are factory filled with 0W-40 dexos2 oil. 0W-40 dexos2 engine oil is approved for both track and street use with the LT1 and LT4 (ZL1 only, not ZL1 1LE) engines. 15W-50 full synthetic engine oil may also be used for track use and is required on the ZL1 1LE, but after track use must be changed back to 0W-40 dexos2 for street use.

ZL1 = 0W-40 both track and street
1LE = 15W-50 full synthetic track, 0W40 street

Licensed 0W-40 dexos 2 brands: http://www.gmdexos.com/brands/dexos2/index.html

Castrol Edge
Mobil 1 ESP
Mobil 1 ESP Formula
Mobil 1 ESP x3

Kinda narrows the field.

Not saying the book is wrong, but the book is wrong.

Your table should say:

SS 1LE/ZL1 - 0w-40

ZL1 1LE - 0w-40/15w-50

However, there is no difference between the LT4 in the ZL1 and ZLE. So I have never been very clear on the reason for the switch.

Regardless, either 0w-40 and/or 15w-50 apply and only Mobil 1 and Castrol appear to make 0W40.

The answer given from the Camaro team was the increased G loads capable in the ZLE require a thicker oil in the wetsump to avoid cavitation.

Ok. That’s good to know. Learn something on the board every day!

It's odd that the subject Mobil 1 0W40 bottle does not have a dexos 2 indicator on it but the X3 does

Just to make matters more confusing:

Most Castrol Edge you will find in stores is the A3/B4 variety, which is not Dexos 2 certified. I don't believe the Dexos 2 certified Castrol Edge is sold in North America, at least not in the 0W-40 viscosity.

So you are pretty much stuck with Mobil 1 ESP if you wish to follow the Dexos 2 recommendation.

I spoke with my Chevy dealer today who said they use Mobil1 ESP.

Here they say Castrol EDGE 0W40 is dexos 2 approved (?) https://msdspds.castrol.com/bpglis/FusionPDS.nsf/Files/29D862369255C1598025838300446319/$File/BPXE-B8NBC4.pdf

See my thread on oils in Mechanical section. First sticky at the top.

BTW since Valvoline MST changed its recipe and lost Dexos2 certification i have been using Motul 8100 5W40 Dexos2.
Plenty of other Dexos2 certified oils on GM list in that weight for much less than Mobil1 0W40 Dexos2.

Arguably, 5W40 will give one better cold start protection, except for very cold winter temps.

Anyhow, not gonna repeat what has been stated in the sticky. Please read it - it is all there and it is current.

Cheers!

There are only 4 GM approved 0W40 dexos2 oils listed at http://www.gmdexos.com/brands/dexos2/index.html

yes the choices in 0w40 dexos2 are limited and clearly GM wants us to go to their dealer and pay mucho dinero for an oil change. And i get it :)

Also, not knowing how one uses the car, a manufacturer will specify the safest choice, such as 0w, in case folks decide to drive their Camaro in -20 temps...And i get that as well :)

BUT:

There is no reason to limit ourselves to this choice alone, as 5w40 Dexos2 is just fine for both street/track (as officially published in 2019 Track Preparation Manual) and so is even 5w30 Dexos1 (fully synthetic) albeit for DD only.

The only exception is ZLE requirement to use 15w50 for track only due to G3Rs, BUT many, many, many folks track their 1LEs with G3Rs with w40 oil.

Cheers!

^ Agree. 5w/40 dexos should be absolutely fine. I think that would mean Amalie or Havoline Pro DS.

I just picked up some Royal Purple 5W-30 for my next change when the cam/heads go on, gotta have that zinc. On sale saved 12 bucks a jug.

Yep. Many other choices on GM Dexos2 list.