High Pb with 5w-40

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486
Location
Michigan
I've done a few oil analysis with a 7.3L powerstroke engine I swapped into my 94 F250. Before I put the engine in I installed new bearings. The first four analysis were with Schaeffer 5w-40 and then I did two with Service Pro 15w-40 and then I did one with Delo 400 5w-40. The lead numbers are noticeably higher with all the 5w-40 results. Do you think this is something I need to worry about? I like using the 5w-40 in the winter as it helps my HEUI system run a lot easier. Miles 5100, 10200, 13800, 9650, 5010, 9371, 9777 Oil Sch, Sch, Sch, Sch, SP, SP, Delo Iron 25, 31, 37, 35, 18, 30, 38 Chrm 0, 0, 1, 0, 1, 1, 1 Alum 2, 1, 4, 3, 11, 15, 6 Copp 6, 10, 15, 10, 5, 7, 6 Tin 4, 6, 7, 4, 5, 7, 6 Lead 13, 23, 31, 35, 11, 17, 34
 

sdan27

Thread starter
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486
Location
Michigan
42, 37, 43, 23, 8, 8, 7. I figured that the high numbers came from rtv, gasket material when I put the engine back together.
 

gathermewool

Site Donor
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New England
Any major difference in the detergent packages? What's the difference in the 100C Cst? It might just be a difference in chemistry composition causing non-detrimental spikes in lead. Just spit-balling
 

sdan27

Thread starter
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486
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Michigan
Do you think the lead numbers are something I should be concerned with then? Do you think its coming from my bearings or somewhere different.
 

dnewton3

Staff member
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Indianapolis, IN
Pb in those engines generally has one source; bearings. I cannot tell you which one(s). Could be the ones you replaced; may not have seated well and now wearing. Or could be an unrelated bearing (one you didn't replace) that has finally got into damage. When you mention "new bearings", which ones? Crank, rod, cam, turbo? At first blush, it seems the Cu went up and Pb followed, but when taking OCI duration into account, the numbers are not staggering. Generally, the only metal that will accumulate with miles is Fe; the others should tend to have a bit of wear and then stagnate over the OCI. Everything you've tried has been a 40 grade. If you want better starting, why not try a 30 grade? Perhaps see if that will do as well. I'm not suggesting this because I think "thinner" will do anything for the wear; it's just a nod towards your concern for winter. At this point, if you try a 30 grade and the wear does not get worse, and it helps in winter starts and idling, then you can settle on one fluid, pick one OCI duration, and then track the wear. You cannot really track wear well jumping around in fluid and OCI duration.
 

sdan27

Thread starter
Messages
486
Location
Michigan
I did the main and rod bearings. I used Clevite bearings. I'm going to see if the numbers stabilize a little more with the 15w-40 and if it does I'll probably try and find a 10w-30. Most HD 10w-30s available where I live are semisynthetic so we'll see if those bring up my lead numbers too.
 
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