oil question

[jhicks]

Yes ive searched.. no real definite results.

98 c1500 vortec 350 155k miles

all I want to know is will it hurt to run 15w40 rotella. Ive always ran 10w30 Castrol.

Ive read that the rotella has a higher zinc and detergent level than every day oils.

anyway, any help would be nice.

 

[kennythewelder]

I used Rotella 15w30 in my 1997 5.7L (350) for about 1 year. It is grate oil. I now use Valvoline 10w40, because it is also very good oil also and it can be found any where. I use to use Castrol GTX in that same truck, but after I took the intake off to fix a leak, and found a lot of sludge in the lifter valley I would not GTX in my lawn mower. I bought my truck from the original owner 8 years ago. He had always changed his oil and filter every 3000 miles and used GTX ( I saw the reseats ) so I keep using GTX for about 3 years and did the same ( every 3000 miles.) But after I saw all that sludge in the lifter valley, I will never use GTX for anything. My truck now has 207,000 miles and runs grate, and it dose not use a drop of oil in 3000 miles. LOL so YES you can use Rotella 15w30. It just may help to clean out the engine, it is very good oil.

 

[454cid]

Yes ive searched.. no real definite results.

98 c1500 vortec 350 155k miles

all I want to know is will it hurt to run 15w40 rotella. Ive always ran 10w30 Castrol.

Ive read that the rotella has a higher zinc and detergent level than every day oils.

anyway, any help would be nice.

Use 10w30 Rotella. 10w30 is GM approved for our engines, 15w40 is not.

 

[TerryD]

My family has run 10w30 Havoline in the winter and 10w40 Havoline in the summer as long as I can remember and have always gotten good service out of our engines. I get it at Sam's Club by the case so price wise it it's about the same as a store brand stuff. My 00 5.7l has ~280k on it.

 

[michael hurd]

Unless the engine is literally on it's last legs and you are trying to compensate for large clearances and low oil pressure, I would not run 15w40 in it. I would run the thinnest oil that you can, as it will have oil pressure faster at start up, and less wear.

5w30 synthetic or lighter is what I run. I have 0W30 Mobil1 synthetic in my 5.0L vortec, it starts in cold weather like it's summer.

Diesels, particularly older diesels have a lot of soot and ash particulate that gets by the rings into the crankcase, this is what that Rotella was geared to.

Higher zinc levels are good for flat tappet cams, which a vortec does not have, they have a steel billet roller camshaft.

 

[jhicks]

I guess I should've specified what I was asking lmao.

I sell oil. the differences in oil and all that jazz, I know.

I was just curious as to if the vortec 350 has the clearances to handle 15w40. ha ha.

I have what sounds like a lifter tap on start up when its cold or hasn't been run in a while. just trying to find an oil to shut it up and possibly clean it.

thanks for all the help folks.

 

[98_k1500]

Its probably "cold knock" on startup, not lifter tap. Its pretty rare one of these engines actually eats a lifter. Much more commonly caused by tight wrist pins. Thicker oil is not going to help this.
Stick with the 10w30.

 

[jhicks]

Its probably "cold knock" on startup, not lifter tap. Its pretty rare one of these engines actually eats a lifter. Much more commonly caused by tight wrist pins. Thicker oil is not going to help this.
Stick with the 10w30.

"cold knock" that's honestly a new one for me. ive heard of piston slap lmao.

huh, I guess you learn something new everyday. its still just driving me batsh** crazy.

 

[98_k1500]

Mine does it bad. Vortec 350s are way worse about it than the TBI motors. Its caused by a tight fitting wrist pin that rocks the piston back and fourth in the cylinder. As the piston heats up, the fit gets slightly looser and the clacking sound goes away. Similar to piston slap but goes away with a little heat.

 

[kennythewelder]

A lighter weight oil is what you want. 5w30. You asked if you could run Rotella, the answer is yes, I ran it in my truck. I live in south Louisiana and it is hot here.(70+ today) It get into the high 90s in the summer, and I'm sure that was a factor in the sludge built up that happened to me. If the lifters are tapping (valve click) a thinner oil will help some (5w30) If the ring are letting oil by and then engine is burning it off then a thicker oil is needed to help stop this. I know that Havoline is good oil. As far as the synthetic oils, there are very good, LOL except Castrol, I have seen this first hand, the sludge issue again. Like I said, maybe it is because of where I live, and all the heat.