Do i need zinc additive?

[Ribbedroof]

I knew what you meant. One never really knows what is what, think of how many people put late heads on early stuff, and since there's no history, it could be anything.

I know of 2 different '88 half-ton truck 350s that were cast as roller blocks, that were factory-delivered with flat tappet camshafts....I'm sure there was some GM internal flowchart as to what got which valvetrain, as I imagine was the case with the aluminum core supports in BOP G bodies.

 

[ck80]

I recommend a good diesel oil with the high zinc until you know better.

It's cheaper to get a quality diesel one and change it every 3k miles, than it is to buy modern car oil then buy and add a zddp-type additive and wait every 5-10k miles.

 

[Trottiert]

I recommend a good diesel oil with the high zinc until you know better.

It's cheaper to get a quality diesel one and change it every 3k miles, than it is to buy modern car oil then buy and add a zddp-type additive and wait every 5-10k miles.

I appreciate the recommendation!
Should I look into an additive now as I've just changed it, or drain it and replace with.... what is a quality diesel oil?

 

[melloelky]

I recommend a good diesel oil with the high zinc until you know better.
It's cheaper to get a quality diesel one and change it every 3k miles, than it is to buy modern car oil then buy and add a zddp-type additive and wait every 5-10k miles.

the diesel oil's aren't what they use to be as they're emission bound now.seeing you've already changed the oil,drain out the amount of addtive that you'll be adding,add the addtive and go from there.if your THAT concerned and have the $$ swap the oil for something designed for a flat tappet with the higher than normal level of zinc/zddp.

 

[ck80]

the diesel oil's aren't what they use to be as they're emission bound now.seeing you've already changed the oil,drain out the amount of addtive that you'll be adding,add the addtive and go from there.if your THAT concerned and have the $$ swap the oil for something designed for a flat tappet with the higher than normal level of zinc/zddp.

As of December 2019:

15W40 CHEVRON DELO 400LE Diesel Oil, conventional, API CJ-4, CI-4 Plus, CH-4, CF-4,CF/SM, = 73,520 psi
zinc = 1519 ppm
phos = 1139 ppm
ZDDP = 1300 ppm

15W40 “NEW” SHELL ROTELLA T Diesel Oil conventional, API CJ-4, CI-4 Plus, CH-4, CF-4,CF/SM = 72,022 psi
zinc = 1454 ppm
phos = 1062 ppm
ZDDP = 1200 ppm

CASTROL GTX DIESEL, 15W40 conventional, API CJ-4, CI-4 Plus, CI-4, CH-4, CG-4, CF-4/SN
“Load Carrying Capacity/Film Strength” = 66,323 psi
zinc = TBD
phos = TBD
moly = TBD
total detergent/dispersant/anti-deposit build-up/anti-sludge TBD
TBN = TBD

Not my personal testing, but came through an old inline 6 engine modifying forum

 

[Trottiert]

As of December 2019:

15W40 CHEVRON DELO 400LE Diesel Oil, conventional, API CJ-4, CI-4 Plus, CH-4, CF-4,CF/SM, = 73,520 psi
zinc = 1519 ppm
phos = 1139 ppm
ZDDP = 1300 ppm

15W40 “NEW” SHELL ROTELLA T Diesel Oil conventional, API CJ-4, CI-4 Plus, CH-4, CF-4,CF/SM = 72,022 psi
zinc = 1454 ppm
phos = 1062 ppm
ZDDP = 1200 ppm

CASTROL GTX DIESEL, 15W40 conventional, API CJ-4, CI-4 Plus, CI-4, CH-4, CG-4, CF-4/SN
“Load Carrying Capacity/Film Strength” = 66,323 psi
zinc = TBD
phos = TBD
moly = TBD
total detergent/dispersant/anti-deposit build-up/anti-sludge TBD
TBN = TBD

Not my personal testing, but came through an old inline 6 engine modifying forum

Wow, thank you

 

[ck80]

Wow, thank you

You're welcome.

Manufacturers change their formulations from time to time.

I've been a delo guy, BUT, that was also helped by being able to buy it in bulk through the big box club.

However, for additional piece of mind, there are companies out there that will send you sample tube and will analyze the oil you send in. When draining your pan hold the tube in, mail it off, 4-6 weeks later you get a report of everything that was count in the oil. So if some bearing somewhere was wearing and putting fine metal in, you can maybe see a spike before you spin something and eat a crank.

Also gives an idea of what the oil condition was based on your driving area/style to decide how far to go between changes.

One thing to beware of, to earn the "grade" rating in the given content categories, the "acceptable" levels in PPM can vary 1000-1400. So oil A and B can be same grade and equal ratings. Oil A could have 950PPM, Oil B could be 1275PPM. Both carry the same labels if the criteria was to fall between 900-1300ppm for certification.

Then again, same thing can happen within the same company, product, and grade as well.

 

[Kennybill]

Here's a good site.

Bob Is The Oil Guy

Bob Is The Oil Guy

www.bobistheoilguy.com

 

[Yav8]

There is a easy to check if it hyd or flat tappet. Just pull a push rod and check the length. Hyd rollers are 7.195 and the F/T are 7.800.

 

[fleming442]

Rotella is cheap semi- insurance