oil recommendation - '89 chevy 5.7L truck

[DaWhip]

Well, this is my intro too. I am an aspiring oil nerd and this is my obligatorily oil recommendation thread. This is a quote from an email I got from the PO and I have no reason not to beleive him:

"Sam, I use Castrol GTX High Mileage 10w-40 year around.I try and use a Wix filter, but a mid to better range filter works fine. It never went over "every 3000 miles". I feel certain you are good for another 2000. It was 2 months or less since last OC. I drove it several times a week to work and back.I also put a quart of Lucas Oil Treatment every OC."

He was the 2nd owner and had the truck since 2000.


The Truck - 1989 Chevy C1500 350cid (5.7L) w/ 145,000 miles

The service manual - use SF/CC or SF/CD. OK to use SG when it comes out, but wasn't out at time of manual print. 10w-30 for temps above 0*F.

Where I live - Austin, TX. lowest temps I will see is in the 20s. It was over 100*F all last summer.

How I Drive - Like an old lady. haha. I have motorcycles to go fast on. The truck rarely goes over 60mph. I accelerate slowly, i brake slowly. The wife drives the truck a couple times a week and she has a heavier foot that me, mostly on the take offs.

My Daily Drive - Our motorcycles are our daily drivers, so the truck doesn't get a lot of miles. 10 mile RT commute on Rainy or cold days, trips to the lumber yard, etc. Every once in a while it gets 2, 400lb motos thrown in the back along with some camping gear and makes a 2-500 mile road trip.

Known Problems - None that I know of. Doesn't burn a drop of oil. Doesn't even have very high miles for it's age.

My thoughts on the oil. Since the truck doesn't get a lot of miles, I am leaning toward something with a longer OCI. Amsoil maybe? I don't want to sacrafice the engine life though, so I am willing to do 3 month OCs if that is the better route. I am a fan of full synthetics. I think the PO did a fabulous job maintaining this motor, including his oil selection, but I would leave the Lucas Oil out, personally. Should I keep doing what he was doing, minus the lucas oil, or switch it up for a longer OCI?

 

[OVERKILL]

Any decent 5w30 would be fine. Though 15w40 would be fine too.

 

[dsmith41]

Yeah I'd put 15w-40 Rotella in it. Cheap, easy, great oil.

 

[tomcat27]

you're gonna hear all possible answers here! me? I'd go 10-30 or 15-40 and skip the Lucas. I'm a huge fan of synthetics but it really shouldn't matter - especially with the 5.7

 

[DaWhip]

Originally Posted By: tomcat27
especially with the 5.7


Why? Educate the noob. I'm coming from motorcycles that are very picky with oil.

 

[panthermike]

Originally Posted By: DaWhip
Originally Posted By: tomcat27
especially with the 5.7


Why? Educate the noob. I'm coming from motorcycles that are very picky with oil.


They are just flat out good engines. My friend sold his 94' 5.7 w/ 300,000 miles, all on dino oil, 3-5,000 intervals.

 

[HyperJinx]

+1 on the 10w30 as well.

I like Rotella T but its harder to find and I usually have to mail order it. A 10w30 Maxlife should be good also.

 

[jstutz]

I have a very similar engine and 2 4.3s that are similar. From the research i have done on the internet and this site, the answer really is you can run whatever you want too and it will last a very long time. If you are looking for the "best: then you really have to access your driving patterns and style. You mentioned that you drive it easy with no racing or extreme towing. You mentioned that you dont get a lot of miles on it but what does that mean. Do you drive it 20 times a year for 100 mile trips, or 100 times for 10 miles. If you do a lot of short trip driving, then you are not benefiting anything from going to a thicker 15w40. If you are doing a few long trips, then the benefit of the thicker oil could come in to play. The question seems to be very difficult. It should set your mind at ease knowing the 5.7 is easy on oil and will survive a very long life on just about anything you throw in it. For your temps, I would not go less than a 10w30, just becuase it is not necessary and the 10w30 is usually has a slightly higher HTHS and lower noack volatility % than its 5w30 brother. Usually the diffenence is almost nill but you really wont be taking much advantage of the cold flow advantages of 5w30 over the 10w30 so it is a slight win to use the 10w30 over 5w30. Having said that, many people in warmer climates run 10w40 and 15w40 with great results. This is where you come in to access if the heavier oil is necessary. It seems like a good quality 10w30 or 10w40 is middle of the road and will offer decent cold weather flow for winter and good higher temp performance. If PO ran GTX 10w40, just keep using it. its a good oil and a very nice fit for your enviroment. I like the synthetics but for your 5.7, so many people ran them so long on nothing but cheap dino, it is really hard to justify the cost. I run synthetics in my 5.7 and 4.3 becuase i dont care about the cost that much. I usually but PP at walmart for 20 dollars. So 50 dollars a year for oil is not a big deal compared to gasoline and it makes me feel better. Good luck.

 

[daman]

A thick 15w40 is not needed in that engine,any 0w30,5w30,10w30 is plenty,it's just a gas V8 nothing outa the ordinary.

 

[DaWhip]

Alright, so I can put just about anything in this motor and it will be happy.

Any disadvantage going with the Amsoil and doing 1 year OCI? I doubt it will see 10,000 a year. Probably closer to 5000 a year. Any Amsoil specific recommendations?

I'm thinking Amsoil for the extended OCI, and if it hits 5k, do an OA and go from there. Reasonable?

 

[daman]

Originally Posted By: DaWhip
Alright, so I can put just about anything in this motor and it will be happy.

Any disadvantage going with the Amsoil and doing 1 year OCI? I doubt it will see 10,000 a year. Probably closer to 5000 a year. Any Amsoil specific recommendations?

I'm thinking Amsoil for the extended OCI, and if it hits 5k, do an OA and go from there. Reasonable?

No disadvantages when going with a synthetic,but you do need to run it out to get your money woth outa
the oil,5,000 on amsoil is a BIG waist. run the amsoil for as long as it takes to hit 10k if it's two years
no problem oil will be fine. ive ran synthetics that long and longer.

 

[DaWhip]

Cool. Thats what I wanted to know. I have no problem waiting till I hit 10k or more. For the way I drive Amsoil suggests 25k interval. When should I do an OA to check on things?

 

[daman]

Amsoils clame of 25k is misleading IMO,, very few engines are capable of going that long, every engine wears out oil at a different rate so what's good for one engine is not going to be good for another,one cant just throw in oil and drive 25k that's absurd.

up to you put 6-7 on and pull a sample, but that ol 350 will live a long happy life with out a UOA, just oil changes and she's good for 300,000.

 

[hominid7]

I'd feel better changing it twice or thrice a year at 3 or 4 thousand miles using pennzoil 10w30 dino oil than changing it once a year with expensive synthetic.

 

[HyperJinx]

I am not going to drive over 7,500 miles on any oil no matter what the claim is. I will spend another $50 a year (per vehicle) and sleep good at night.

 

[1WildPig]

Welcome DaWhip, I've got the same motor in my '90 Chevy Silverado that belonged to my late father. I've just completed an ARX clean phase and am now in the rinse phase with regular Quaker State 5w30 ... I want to keep it in tip top shape as it has always been well cared for. In your neck of the woods, using what was used before would be fine, but I'd be inclined to use Valvoline Maxlife Semi-Syn blend in 10w30 or 5w30 - maybe 5w in winter and 10w the rest of the time.

Like you said, I'd leave out the Lucas. I'd also add 16oz of Marvel Myster Oil now and run it til the next change and then do an OCI with one quart of MMO in 4 quarts of either a 10w30, 10w40, or even a 15w40 depending on the temp. I went the AutoRX route but if I was doing it over, I'd try MMO first. I also use the MMO in the gas with every tank as my truck sits a lot.

I too am a fan of full synthetic oil (Amsoil) and am even a dealer, but for my application with it's low annual miles, it just doesn't make sense. When it was in semi regular use by my Mom it got Amsoil 10w30 with annual changes with around 10,000 miles. Now, it only sees about 1200 to 1500 miles yearly. After I get thru with all the "cleaning" I'm thinking on possibly going with Valvoline Maxlife SynBlend in 5w30 or maybe the 10w30 with a little MMO added in the winter time for thinning and maintenance cleaning.

From one biker to another, take care out there...

 

[BRD]

OK, I'm no expert but here's my 2 cents. For the amount of miles you put on the truck a synthetic is a waste, at least the amsoil. If you want to run one just run one from wally world. In the Texas heat thicker oil is ok, maybe better. No need for 0w anything. If it burned oil I would say go with something like 15w-40 or even straight 30, but it doesn't so good old 10w-30 would be my pick. If you went synthetic maybe 5w-30.

 

[BRD]

Oh and leave out the oil additives. Don't need them. No mmo, arx, and no lucas. The GM 5.7 runs forever. It's not a sludger so don't try to clean it. Most other additives just thicken the oil. If I did want to clean it or keep it clean I would just run a synthetic. If its never had a synthetic in the pan I would change the filter about halfway through the interval just to be on the safe side the first couple of changes.

 

[daman]

Originally Posted By: BRD
OK, I'm no expert but here's my 2 cents. For the amount of miles you put on the truck a synthetic is a waste,

He plans on running it out 10,000 miles and a synthetic a wast??

1-Synthetics have better cold weather flow/starting performance

2-(can take the heat better)can protect better in hot severe driving/towing conditions, better Hot weather protection

3-cleaner operating engines,less varnish, sludge etc..

4-capable of extended drains

5-some people better gas mileage

is just a few reasons,,,the price is justified when ran out longer intervals. A thinner oil would also protect just as good in the heat,i tow 12,000# often in 80-90deg. summer heat running 0w30AFE in my 230,000 mile Z71,a thicker oil is not needed in that 350 V8,trust me been there done that.

 

[fascination127]

357K on my 6.0 chevy 2500 on Amsoil 10W30 full synth on 10K OCI. Runs like new. Amsoils the real deal... but you have to go 10K+ to get your moneys worth. Or just do easily accessable quality oil and a sane interval.