OP
I was think of running either Castrol HM or Valvoline 10w-40 and possibly adding a zinc additive? I prefer to run 10w in the summer.
Noisy 4.0
- Thread starter MrBClark
- Start date
High mileage oils have increased amount of seal swellers and conditioners. Not recommended unless you're trying fix a leaking rear main seal without replacing it.
Also dont buy into the oil additive marketing hype. There are no good oil additives. The only thing oil additives can do is make a high quality properly formulated engine oil perform worse. If after researching you come to the conclusion that your engine could benefit from increase zinc or any other modifier use an engine oil that is already formulated properly. No additive should ever be required.
Here's what I'm about to use
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OP
I am currently using that same oil. Just with a Mopar filter. I am probably going to use Valvoline Maxlife 10w-40 next oil change just because I want the 10w for warmer months. Also kinda hoping it suppresses my engine noise on startup a little bit.
Using a 0w oil isn't a real good idea in these older engines. First off you will have a much thinner lubricant film in the bearings. Parts are made to work with a certain film thickness to provide protection. Secondly, these are older engines that already have some bearing wear meaning they would prefer a thicker film to make up for bearing wear.
OP
I think you misunderstand how oils are rated by weight.
Sae 0 weight oil is way thicker at 0 degrees c than sae 50 weight oil is at 100 degrees c.
The first number, lower is always better. 5w30 oils are made from more pure base stock oils than 10w30. The secret I'm gonna tell you now... listen, the only advantage a 10w30 has over a 5w30 is... lower price, maybe.
OP
Then why does the owners manual suggest 10w for warm weather? Some older 4.0/4.2s even suggested up to 15w to 20w for hot weather. The owner manual only suggests 5w when it gets cold
Because it costs the dealership less money to use 10w30 than it does 5w30... 5w30 will give your engine better startup protection than 10w30. That's a fact.
Like I said, price on the shelf should be considered a marketing ruse as well. The seller makes higher profit from 10w30. If they were priced at the same margins, 10w30 would be about $1 less per qt.
OP
So just to be sure, the sound in the video is normal to you if it goes away in like 5-8 minutes of driving?
Aviatortroy
TJ Enthusiast
Just to be clear, MMO is not mostly ATF, in fact not at all. It is one of the very few oil additives approved by the FAA for certain applications (mostly used in radials) and I saw an analysis that shows it’s actually mostly light distillate oils and Stoddard solvent. If anything diesel is way harsher and also definitely not an approved method.
If you follow the directions it suggests replacing one quart of oil with a quart of MMO and driving like that for one entire OCI. I myself feel that the solvents would have done their job of dissolving sludge and then evaporated long before the 3000 mile point. So if you do decide to go that route keep a close eye on the oil level. Adding a quart 1000 miles before my next planned oil change worked for me. But I still consider that a drastic treatment and 1-2 oz per quart of capacity and run in the whole OCI has been proven to be a gentle way to slowly clean up some sludge from a higher mileage engine.
You really don’t want to go too drastic, I had an older Volvo that I did a true flush on once and it caused a couple seals to leak and I had to drop the pan and clean off the pickup because it got plugged up with junk that got dislodged.
You have obviously had different experiences with it than I've had. I have never heard of mmo being anything other than predominantly atf. Regardless, it seems to work better on some engines than others. Using a few ounces has never been enough to cure sticky hydraulic lifters in my experience, but if it works for you, great. So many claim that mmo or any other oil additive is purely for suckers and has no effect at all, ever, never.