2003 Jeep w/4.0lt. Schaffers 10w30 w/ Motor Guard bypass filter

[plexx]

The oil was run for about 7 months, with element changes at 1200 miles,( 2 changes).Jeep is a 2003 Rubicon and has 13,895 miles on it.


Aluminum 1 2
Chromium 1 1
Iron 7 9
Copper 10 8
lead 2 3
Tin 0 0
moly 93 85
silicon 7 9
sodium 1 2
magnesium 17 13
phosphorus 699 709
zinc 842 855
barium 1 1

visc.was 55.3 flashpoint 360 fuel 0.8 (all short trip driving , 5 miles each way) antifreeze 0.0 , water trace ( sample was taken when engine was to cool, insolubles 0.1 , TBN was 3.2 ??. It seems the bypass filter is working, but with the tbn so low it might be time for me to change the oil anyway. Should I try a different type of oil or give up on the bypass and just change the oil every 6 months? Thanks Chris

 

[Al]

How many miles are actually on this oil. I woujld go with a more complete oil analysis like Blackstone.

 

[Gary Allan]

If your short trip deal is permanent ..get a light 30. You're never (probably) below a 50 weight by the time you turn off the key. Your fuel is an issue here. You may need to have your PCM flashed to get that under control ..although the 4.0's coolant warms up incredibly fast. In warm weather it's at operating temp in less then a mile. Maybe a little over 2 in colder weather.

Like Al says, we don't know how many miles this has gone. If you get the fuel under control, then you can probably keep going on the same sump with the bypass filter. The deal is that you're subjected to a good bit of moisture retention with your short trip usage and this depletes the TBN. You may get to a JIT (just in time) TP swap that might keep your TBN in the safe zone but all the stuff I've absorbed here says that fuel needs to be below .5%

 

[MarkC]

Is the TBN really that low at 3.2?
Is that copper a bit high? What causes that, anyway?
Gary, can you talk abuot flashing the PCM a bit?

 

[plexx]

Sorry, there was 2,543 miles on this oil, the fuel is due to short trips and the 4.0's are known for running alittle on the rich side. What I am wondering is if the bypass filter is helping at all, if the tbn is shot at 7 months and 2500 miles, maybe I should just change the oil every 6 months and be done with it. Thanks for the replys. Chris

 

[MarkC]

I'll ask you again, why do you say the TBN is shot at 3.2?
My last UOA had a TBN of 3.1@3000 miles and I was told by "somebody who knows about this stuff" that it was still good for another 1K or so.

 

[plexx]

Mark; the analysis was done by Blackstone's and they said that being that the TBN was at 3.2 that I should change the oil soon. Since I am running a motor guard bypass filter with element changes at 1200 to 1500 miles and about 1 qt. of oil being replaced every time the element is changed , that the additive package would be in alot better shape. Since the Schaffers is a synthetic blend I thought it would hold up better and I would be able to extend the oil chang intervals. One thing, since this is all short trip driving and mostly during the winter, maybe the Schaffer's and bypass filter did a great job. Who knows what the numbers would have been with this set up.

 

[Bio-T]

I think the Schaeffers did an excellent job. The TBN of virgin Schaeffers starts at 8.0 if I am not mistaken. So even though you ran the vehicle under less than ideal condiditons, your TBN dropped less than 4.8, Consider if it had started at 12.0 and dropped to 3.2, then you have a problem. Run that oil another 2K, but try a longer hot summmer trip of 50 miles once in a while.

Personally I don't waste money on TBN on a gas engine. I just don't think it is important. I look at the wear numbers and the fuel and insoluables. That tells me what is happening. (And for insurance, I send it to Dyson Analysis and he tells me things about the analysis that I could never figure out)

 

[LargeCarMan]

For 2,500 miles on the oil and at least 2 TP changes and refills....it's not working for you. You need to re-think viscosity, or brand of oil, or type of oil....or all three!

I would loose the Motorguard and go full synthetic.

 

[Bio-T]

LCM,

Could you explain what the full synthetic will do for .8 fuel dilution? What will full synthetic do for almost no wear particles during the winter? Also how can full synthetic improve on the .1 insoluables.

Why lose the Motorguard?

 

[LargeCarMan]

My personal feelings are that until the fuel dilution problem (until repaired or managed) can be fixed, there could be a problem with ring sealing in the future. If a full synthetic of choice can be used now...it might better protect the engine if the fuel dilution remains.

2,500 miles on this oil with at least 2 makeup quarts for the TP changes does not say good for the TBN level. The rest looks great. I guess the reason I don't like the Motorguard is the constant replacement of TP rolls and adding more oil all the time.

I would think that a full synthetic oil at this time or trying different viscosity, types, or brands might give plexx better results.

 

[Bio-T]

LCM,

This is just me personally. If I lived up North or in any part of the country that has cold winters, I would use nothing but synthetic. Faster warm-up, better cold flow in most cases and many other good reasons. My personal observation is that this would reduce fuel dilution somewhat. But now I live in a pretty mild climate year around, so I can use either dino or syn. So I use both.

I would still keep the MotorGuard because it can remove up to 4 ounces of condensation. That is why I think the short trips did not show any moisture other than a trace.

 

[Gary Allan]

quote:

---

Originally posted by MarkC:

Gary, can you talk abuot flashing the PCM a bit?

---

The PCM has premapped fuel and timing curves for open loop operation. Warmup, WOT, etc. Sometimes, due to the manufacturing variable, these standard settings don't work well. My 2.5 was already flashed from the factory. That is, it already had a "been flashed after the original programming" sticker on the PCM. Sometimes they discover drivability issues later on in the vehicles lifespan ..and recommend that the dealers flash PCMs as they come in for warranty or service. In my case, I may have to have it flashed again since midgrade fuel appears to provide a less chaotic high rev engine. You can only reflash the PCM twice.

For most situations, your adaptive cells will broaden or narrow your injector pulse width according to how many rich or lean conditions are recorded during open loop operation. This is where the MAP sensor is the only sensor (IIRC) that dictates what curve the PCM is going to use. Too many leans ..it advances (broadens) the injector pulse width for the entire open loop operation. Too many rich conditions ..it narrows the pulse width. This is how the system attempts to compensate for reduced fuel pump pressure/clogged injectors ..or leaking injectors.

There are no knock sensors in the jeep inline engines.

Anyway, his firmware may be able to be modified to correct this fuel situation.