syn oil options for an LT1

[Benedikt]

This is the lower-hp higher-torque LT1 in a 96 Roadmaster wagon. Lots of short and medium trips (Home Depot and several other stores are 1/2 mile away, other frequent targets 5-15 miles, lots of surface streets with 5 miles of interstate in the middle) and occasional 150-250mile all-interstate trips; north AL just-below-freezing to 4 months at 90-100 degree weather. About 144k miles.
(The same questions below also apply to a 92 Roadmaster L05, i.e. previous-gen smallblock 350, that gets a slighly hotter version of the same weather in Auburn AL and the same driving plus more 250-mile trips up here. About 130k miles.)

After years of Mobil 1 5w30 and 10w30 up north, I found BITOG and references to Mobil 1 xw30 being a bit thin, and the Mobil 1 5w40 I have around for my TDI anyway. Also, every time the Mobil 1 5w40 got hard to find, I used GC. (I have another wagon like this that got to 222k+ miles with the same treatment, and is only now dying of frame rust.)

These days, GC is always $8/qt. for me and I read it's possibly a little less miraculous compared to other oils now than it used to be.
Mobil 1 5w40 is suddenly in plentiful supply at $26/gal at Walmart again, which also has most other Mobil 1 oils that might be considered at $23/5qt.

So the price differences aren't big, but is there anything to recommend Mobil 1 5w40 over Mobil 1 5w30 or 10w30 worth spending probably $9 more per change? Is there something in the ESP (or whatever suffix) oils, or the green-cap 0w30, to recommend them over 5w40 even regardless of price?

I've read very good things (even for TDI use?) about Mobil 1 0w40, but is it appropriate for these kinds of engines?

 

[MetalSlug]

Stick with 5w30, Mobil 1 High Mile 5w30 is what I alway run when it onsale. I alway run Castrol GTX high miles 5w30 on my camaro all year round.

Keep eye on that opsti spark.

 

[tig1]

If your engine calls for 5-30 then use 5-30.

 

[addyguy]

Another inexpensive, excellent option is Rotella 'T6' 5W-40.

 

[CATERHAM]

Originally Posted By: addyguy
Another inexpensive, excellent option is Rotella 'T6' 5W-40.

A way OTT inappropriare choice. A good oil, wrong application.

As suggested stick with the light 5w30 grade.
As an alternative to M1 any other API 5w30 synthetic that you see on sale would also be more than fine.

 

[Brons2]

Originally Posted By: CATERHAM
Originally Posted By: addyguy
Another inexpensive, excellent option is Rotella 'T6' 5W-40.

A way OTT inappropriare choice. A good oil, wrong application.


T6 is not an inappropriate choice for a Chevrolet LT1 engine. These are known to like a thicker oil.

 

[Lead Shoes]

You could use a 40 weight oil in your LT1 if that is what you want to do, Mobil 1 0w40 is one of the best oils readily available today, but if I was you I would stick to the Mobil 1 High Mileage 5w30 or 0w30 GC with a good oil filter like Wix, napa gold or above, purolator, bosch, Mobil 1, K&N.

 

[CATERHAM]

Originally Posted By: Brons2
Originally Posted By: CATERHAM
Originally Posted By: addyguy


T6 is not an inappropriate choice for a Chevrolet LT1 engine. These are known to like a thicker oil.

The spec' oil is a light 30wt. T6 is not a mid-grade 30wt like Mobil 1 High Mileage, or a heavy 30wt like GC or a light 40wt like Mobil 1 0W-40 but it is mid-grade 40wt. So yes I'd say it's an OTT choice.

 

[[RT] ProjUltraZ]

but you do a lot of short trips, that negates 40wt for me. I'd use Pennzoil Conventional 5w30, Valv white bottle, MaxLife or other high mileage, or PP if you want to give it a treat

 

[MetalSlug]

Originally Posted By: addyguy
Another inexpensive, excellent option is Rotella 'T6' 5W-40.


that oil is not work for everything lol

 

[SEMI_287]

LT1's love 40 weights. No reason not to use Mobil 1 0w40, great stout oil for a great motor.

 

[CATERHAM]

Originally Posted By: SEMI_287
LT1's love 40 weights. No reason not to use Mobil 1 0w40, great stout oil for a great motor.

LT1's may tolerate 40wt oil but there's one single important reason not to use it; because you don't have to.

Abide by the fundamental lubrication axiom; "as thin as possible, as thick as necessary" and you will maximize fuel economy, power and engine longevity.

 

[Patman]

Originally Posted By: CATERHAM

LT1's may tolerate 40wt oil but there's one single important reason not to use it; because you don't have to.

Abide by the fundamental lubrication axiom; "as thin as possible, as thick as necessary" and you will maximize fuel economy, power and engine longevity.


I agree! The average street driven LT1 will do just fine on a 5w30 oil. In the past I would often recommend thicker oils to my friends with LT1s and LS1s, but these guys are more hardcore, a lot of them are doing road racing and have more modifications as well (ported heads, larger cam, superchargers, etc.) so in their cases a slightly thicker oil could benefit them. But they are the exception rather than the norm.

 

[Benedikt]

Well, except for floor-it-to-merge once or twice a day, and occasional put-a-punk-in-his-place we don't exactly race, and the only engine mod is a pcmforless.com tune.

I'd never considered that the 5w30 spec combined with the Mobil 1 recommendation could have been done in full knowledge of Mobil 1 5w30 being a bit light.

Given that, what about Mobil 1 Advanced Fuel Economy 0w30?

 

[CATERHAM]

Mobil 1 Advanced Fuel Economy 0w30 is a bit lighter than Mobil 1 5w30 although it will work fine.

 

[A_Harman]

Mobil 1 5w30 HM. I used Mobil 1 5w30 in my LT1 Camaro when I owned one from 1999-2002. I did autocrosses and track days with it. No problem.

I ran Mobil 1 5w30 in my 2002 LS1 Camaro for 158k miles, doing autocrosses and track days all 9 years. Mobil 1 5w30 will do the job for you.