Mobil 1 Motor Oil Question

[angliagt]

            On the '94 Dodge Dakota (4WD/318 V8) I found a partial quart of Mobil 1.

It's due for an oil change,& was wondering if it would cause any problems going

from that to using a conventional motor oil?

[datzenmike]

Chrysler went a roller cam in '84 so you should be ok.

 

Phone a Dodge or Chrysler dealership and ask. This is a Datsun forum.

 

 

[angliagt]

   Yes,but it is the "General Discussion" forum,so I thought it was acceptable.

[thisismatt]

No

[thisismatt]

That was in response to the initial question

[angliagt]

  Thank You!

[Stinky]

I read your question as, can you add a partial quart of synthetic to you motor....let me know if that ain't right.

 

You can use any dern oil that you want....AS LONG AS, it meets the manufacture's recommendation.  You can mix and match weights and types...assuming that they fit what you are supposed to use on your motor.

 

Look at your manual.  If it says that the Mobil-1's characteristics  are good, then you are good.  You can mix 0-30, 5-30, 10-30 ASSUMING that, those are all "safe" oils to use on your motor.

 

Edited December 7, 2022 by Stinky

[datzenmike]

Safe to me is a viscosity not below 10w30 and an anti scuff additive package with at least 1,000 PPM of ZDDP. All conventional gas engine oils are at most not above 800PPM and the majority more like 600PPM. I would stay away from them and I would include synthetic oils as well..

[angliagt]

     No,I found a partial quart of Mobil one under the hood,

so I assumed that's what's in the truck now.

         I was wondering if when I change the oil I could use

conventional oil.

[datzenmike]

What's the ZDDP level of Mobil One. I wouldn't run anything below  1,000 PPM.

[thisismatt]

750-1850 depending on the line/weight. 

[datzenmike]

 

Perhaps the ZDDP rating of the part can of oil (Mobil) he found then.

[thisismatt]

Well Mike, there are like 50 different lines & weights of Mobil 1, so without that inforfsckingmation, I can't say

[KELMO]

I'll chime in with my 2 cents worth.

 

I've heard say that you can go from conventional oil to synthetic but should not go from synthetic to conventional as it could cause leakage.

 

This could be true; it could be false. I am fairly sure I read it on this very site. So, it could very well be bullshit. I mean interwebs and whatnot.

 

Glad I could be of no help whatsoever.

[thisismatt]

44 minutes ago, KELMO said:

I'll chime in with my 2 cents worth.

 

I've heard say that you can go from conventional oil to synthetic but should not go from synthetic to conventional as it could cause leakage.

 

This could be true; it could be false. I am fairly sure I read it on this very site. So, it could very well be bullshit. I mean interwebs and whatnot.

 

Glad I could be of no help whatsoever.

 

I've only heard the opposite - synthetic will clean the internals better and wash any old gunk away that could be stopping leakage/seepage at gaskets.  I do think it's somewhat true...all my old hondas started leaking at the pan gasket and into spark plug holes...

[datzenmike]

I think synthetic has the same detergent package as conventional oils BUT diesel is extremely detergent in comparison to gas engine oils. I've been running diesel oil for 10 or more years and I noticed the first few oil changes the oil would darken very fast. This was due to the detergent removing that brown plated on coating on all internal metal parts.  

 

I tried synthetic. Just a quart to top up. Within days there was an oil drip on the crank pulley from a leaky front seal. After the next oil change the leak slowly dried and stopped soon after. That's my experience with the thinner more slipperier synthetic. I think it can seep past old seals so I don't recommend it. A newer tighter tolerance engine or if you have a turbo, sure. It's just too expensive and extreme an oil for older Datsuns. 

 

[Ranman72]

1 hour ago, thisismatt said:

 

I've only heard the opposite - synthetic will clean the internals better and wash any old gunk away that could be stopping leakage/seepage at gaskets.  I do think it's somewhat true...all my old hondas started leaking at the pan gasket and into spark plug holes...

this is also what i have heard conventional to synthetic could cause leaks 

[datzenmike]

There's no real justification for using synthetic in an old Datsun. But as long as it doesn't start leaking that's up to the owner if he feels more protected with it. Synthetic is slipperier and can get past seals and gaskets that thicker oil cannot. It's not supposed to but that was my experience with it.   

 

Almost forgot. I used a synthetic oil in a 720 transfer case and right away it began leaking from the top input seal which I replaced and this fixed it only to begin leaking from the lower rear and then the front output. I replaced these seals (not cheap) and that seemed to solve the problem. So there's that also.

 

If you switch to synthetic there is the chance that it will seep.

              

[Stinky]

Unless you are going to an extended oil change interval....synthetics aren't cost effective.

 

Standard Dino oil does just fine to 5K miles.

 

Maybe better, if your are getting it w/ZDDP

 

Your motor will be less likely to leak oil w/dino oil.

Edited December 9, 2022 by Stinky

[metalmonkey47]

I'll answer this, having had opportunities to speak to various oil manufacturers years ago for work related training.

Modern synthetic oils can be mixed without consequence. This is why part synthetics or "blends" exist. Ideally, you would stay with synthetic oil because they are better in almost every way. (I say almost because there are some conventionals that have higher ZDDP, Moly, and other anti-wear additives than some synthetics.)
 

If you have an engine that has been on conventional oils its entire life and hasn't been serviced regularly (seals, gaskets, etc) it's possible to see small leaks, but not because the oils are more slippery(they are, but this isn't what causes the leaks). This happens because the synthetic oils have better detergents that can break down old oil/grease residue in seal and gasket surfaces. In these cases, the engines already had oil leaks that resulted in buildup on these surfaces that can act as a "seal" as oil accumulates. The high detergent synthetics can break down some of that residue as it seeps, making the leaks more obvious.

Synthetic oils generally have better lubricating properties so engines that have seen only synthetics throughout their life usually have longer seal life. This is why you should stay with synthetics.

[Thomas Perkins]

I ran Mobil one 10w30 and Mobil one oil filter in my 720 and had no problems.My Jasper remanufactured engine had about 70,000 miles on it.The oil didn't leak anywhere. But I did 2 oil changes and it didn't impress me to keep using it.I went back to Castrol 10w30 and the Wix oil filter.I now have about 100,000 on my Jasper.The spark plugs are still like  new after over 2 years.I use the NGK Iridium's.I don't care what anybody says but I have been using 10w30 for 28 years on my 720.My speedo says 382,000 miles.It says 15,000 miles guarantee production on the oil jug,but when I changed it  way before then,the oil looked real bad.

Edited December 9, 2022 by Thomas Perkins

[datzenmike]

My oil leak at the front seal went away after I got rid of what little synthetic I put in there and returned to 10w30 regular oil.

 

Have a different vehicle now and switched it to, and have been using diesel oil which is always high in detergents for about 12 years now with no leaks started. 

 

Good to 'see' you MM