92 F250 7.3 IDI - amsoil 15w40

[soulpatchfr]

just stumbled across the place - please forgive any newbie transgressions...

'92 F250 IDI w/ 234k miles. old style Amsoil 2qt bypass was there when i bought her in '97. since then i have always used annual oil change intervals, changing both filters at the same time. 15k+/yr lately.
if it matters, in the last few months: first ever Amsoil AF, started using the powderchoke full flow OF, removed CDR & replaced with RDT.

just learned of Blackstone quite recently, & only have 2 samples under my belt - 3rd will be @ 6k+ on current oil, April 01? so, still learning to interpret the results... any help or advice would be appreciated.
obviously, i am concerned about the lead/bearing levels.

----------02/27 / 01/26
---------4223mi / 2750mi / univ avg
Aluminum 1 / 1 / 3
Chromium 1 / 1 / 2
Iron 29 / 25 / 67
Copper 1 / 1 / 6
Lead 15 / 11 / 8
Tin 1 / 0 /1

Molyb 5 / 5 /23
Nickel 0 / 0 / 1
Manganese 0 / 0 / 1
Silver 0 / 0 / 0
Titanium 0 / 0 / 0
Potassium 14 / 0 / 2

Boron 4 / 0 /122
Silicon 2 / 3 / 8
Sodium 8 / 7 / 12

Calcium 3096 / 4149 / 2682
Magnesium 10 / 15 / 218
Phosphorus 991 / 1072 / 1080
Zinc 1080 / 1171 / 1239
Barium 0 / 0 / 0

----------- actual / should be
Sus Visc 74.3 / 68-80
Flashpoint 450 / >410
Fuel Antifreeze 0 / 0.0
Water 0.0 / Insolubles 0.4 /
TBN read 9.0 on the 2750 mile sample, didn't bother for #2

thanks in advance for any input,
Frank

[ March 23, 2005, 03:32 AM: Message edited by: soulpatchfr ]

 

[TooSlick]

Frank,

From the Na and K levels, it looks like you may be developing a slow coolant leak into the oil. This would also help explain the high bearing wear and solids level of 0.4% after a short # of miles.

I'd pressure test the cooling system and look for a hairline crack, or cavitation damage through one of the wet cylinder sleeves ....I believe the cooling system of these motors requires the use of Supplimental Coolant Additives (SCA's) to control cavitation damage to the sleeves....

Tooslick
Dixie Synthetics

 

[soulpatchfr]

thanks, slick, but my novice mind can't see why you say that...
i haven't seen a virgin analysis of the Amsoil 15w40HD, but could the sodium levels be additives? and they compare well with the univ. avg. (@3760 miles, BTW) i did notice the jump in K, but didn't fret much. maybe i should?

also, antifreeze shows 0, water shows 0, & the solids show half of 'should be' values, so

yes, cavitation is a real concern for the 7.3 - as i read just last year. didn't think it related, but a coolant filter & SCA's were added (for the first time) in December.

can you point me towards a link to interpret the results more thoroughly - so i can ask educated questions? of course, i know the Blackstone site well.

 

[Bio-T]

This is a VOA of Amsoil 15W40 that was done 12/27/04, so it is pretty recent:

 

[TooSlick]

Soulpatch,

A drop of the TBN to 9.0 in only 2750 miles is another indicator of external contamination from coolant.

TS