Custom built LS 1 5.3L

[hatcoleman]

Help me select an oil for my classic vehicle. Complete restoration of 1966 Chevy C10, with LS1 5.3 L. Not stock, 430hp rear wheels on dyno.
Engine builder filled with Rotella 15w40. Don't know why he put a diesel oil in gas motor ? Not sure this is best for motor.
I use Rotella 5W40 synthetic in atv, UTV, tractors etc.. But he refused to use it for initial fill. I think he is old school using thick, Dino oil. New Rotella isn't the same as just few years ago. The Rotella 5w40 no longer gas rated.
Motor is 2005 model, GM recommended 5w30. Should I use different oil for my custom built motor ?
Won't be putting many miles on vehicle. Want best oil for protection of motor.
Live in south Mississippi so will have hot summers. Winters may get to 20s.
Appreciate your suggestions. Thank you very much.

 

[CT8]

The builder went with the Rotella because he knows what he is doing.

 

[Linctex]

Originally Posted by hatcoleman
LS1 5.3 L. Not stock, 430hp rear wheels on dyno.


What in the actual *#*&^$............?

What's that.... about 500 HP at the flywheel from a 5.3 ?!?
This thing is a beast. It needs a stout oil.

Just an anecdote: My twin turbo 351W powered Mustang (about 650 HP to the rear wheels) also ran 15w40 Rotella, same as you.

It's really some pretty good oil.

Oh.... and you are in Mississippi... where temps very seldom get cold anyway.

 

[MrHorspwer]

Originally Posted by Linctex

What in the actual *#*&^$............?

What's that.... about 500 HP at the flywheel from a 5.3 ?!?
This thing is a beast. It needs a stout oil.


The thing is... it's not.

Good heads and a well selected cam (but not especially radical) will net you 400+ wheel HP on an LS. OPs truck probably still has a very streetable idle and great driveability. That's why people love them so.

LS engines aren't particularly hard on oil either. Roller cam and rockers are standard fare, most don't require outrageous valve spring pressures, nothing really exotic here.

My go-to suggestion for a work'd LS: Redline 5W30 or 5W40, whichever you're comfortable with given typical ambient (or oil, if you have a temp sensor) temps. I assume you don't flog it daily, so I'd change it once a year and not give it much of a second thought.

 

[bullwinkle]

I put the last of my Delo 400 SAE 30 CG-4/SJ in my brother's '67 283 that he put in his Jeep CJ-7, along with a bottle of zinc additive (flat tappet, fairly high lift cam), believe it was Lucas additive, and broke in the cam at 2000 RPM for 30 minutes, and the engine has been doing fine. Rotella T4 would be a great oil in a built small block, and since an LS should have a roller cam, lifters, & rockers, zinc additive shouldn't be necessary. DId the machinist tell you what the rod & main bearing tolerances were? Because that really determines how thick you should go, along with hot oil pressure during track or after drag runs.

 

[bullwinkle]

Also, I hope you put a locker or posi in that truck, you'll need one! I had a rough '64 C20 long ago that was a short stepside like that one, those trucks are pretty light, easy to do burnouts.

 

[mcrn]

How about Mobil 1 0W-40? Nice truck by the way.

 

[MrMoody]

Nice truck!!! Love it!

Originally Posted by bullwinkle
Also, I hope you put a locker or posi in that truck, you'll need one! I had a rough '64 C20 long ago that was a short stepside like that one, those trucks are pretty light, easy to do burnouts.


Yes, they're so light in the rear that you'll find that some weight in the rear bumper (or as far back as you can get it) will make it quicker because it hooks up better. Assuming you care about that. For all I know, you will just cruise it while everyone drools.

 

[maxdustington]

That's pretty much my dream truck right there, 66 stepside.

Nice truck, Edge 0W40.

 

[CT8]

She is a beauty [ I forgot to add ]

 

[A_Harman]

What is it really?
An LS1 is 5.7L / 346 cubic inches.
Just use M1 0w40.

Love the color of your truck!

 

[addyguy]

Rotella 15w40 is a great oil for that engine - very stout, easy to get, and inexpensive on sale.

Very, very nice truck!

 

[MrMoody]

Originally Posted by A_Harman
What is it really?
An LS1 is 5.7L / 346 cubic inches.

That was my first thought. It's probably an LM7, maybe L33, possibly even LS327 crate engine, or maybe he's just wrong on the displacement.

 

[MolaKule]

This is what I would use for the first 500 miles:

Break-In Oil

and then change over to any good 10W30.

I agree with MrHorspwer, nothing really special unless some aftermarket internals have been put into the engine's rebuild.

Very nice body restoration.

Did you mention the transmission type or did I miss it?

 

[andyd]

Looks like a fine resto-mod. I'd be fine with the six and 3 on the tree it came with. Most of the trades men in town drove one back in the day.

 

[JC1]

Nice truck. You forgot to give us the most important picture of the Motor!!!!

As others have said Rotella 15w40 is good or Mobil 0W-40. I'm waiting for the Supertech Conventional Recommendation. lol

 

[trik396]

I'm interested in responces here because I am in a similar situation with an LS motor that I built for a 1984 Oldsmobile Cutlass that will be more of a pro touring build. Started off with an 02 6.0 that I stripped down and had bored .030 over and using stock crank with forged rods and pistons giving me 6.1 L or 370cu inches. All balanced and blue printed of course. Fully cnc'd 799 heads and BTR cam should put me at around 550hp and trq conservatively. Anyway I am breaking her in with 10w30 dino oil but still have not decided on regular fill. Decisions, decisions

 

[hatcoleman]

We did put posi in rear.

 

[hatcoleman]

It has an automatic tranny

 

[trik396]

Can someone explain to me why Mobil 0W-40 is recommended several times here...? Hope that doesn't open a can of worms....