Amsoil SS 5w30, 9K, 04 Chevy Tahoe

[TXHunter]

Oil was changed at time of sample. Did about 600+ highway miles of towing right at the end of this sample. Probably 3-3,500lbs with a 12ft single axle.

Make/Model: GM 5.3L V-8
Vehicle: 2004 Chevy Tahoe

Code:


OIL Ams SS Ams SS Ams SS Ams OE Ams OE Ams SS

MILES IN USE 9,246 8,124 6,069 3,165 3,008 9,569

MILES ON UNIT 186,682 177,436 175,381 169,312 166,147 163,139

SAMPLE TAKEN 6/29/15 11/30/14 10/23/14 6/23/14 5/6/14 1/25/14

MAKE UP OIL 0 0 0 0 0 0



ALUMINUM 4 3 2 2 3 5

CHROMIUM 0 0 0 0 1 1

IRON 12 9 7 3 7 18

COPPER 10 12 10 6 12 14

LEAD 30 7 6 2 5 14

TIN 5 0 0 0 0 0

MOLYBDENUM 160 144 139 68 89 132

NICKEL 1 0 1 0 2 1

MANGANESE 0 0 0 0 0 1

SILVER 0 0 0 0 1 0

TITANIUM 0 0 0 0 0 0

POTASSIUM 4 0 0 0 1 2

BORON 61 45 53 105 147 49

SILICON 28 31 25 14 18 25

SODIUM 9 9 8 3 7 10

CALCIUM 3461 3247 3475 1944 2284 3195

MAGNESIUM 14 12 15 8 10 13

PHOSPHORUS 627 702 658 658 790 644

ZINC 800 801 767 747 875 690

BARIUM 0 0 0 0 0 0



SUS @ 210F 62.6 64.6 63.8 58.7 58.3 62.9

Visc @ 100C 10.94 11.51 11.29 9.86 9.73 11.04

Flashpoint 420 430 435 410 430 445

Fuel %
Antifreeze % 0.0 0.0 0.0 0.0 0.0 0.0

Water % 0.0 0.0 0.0 0.0 0.0 0.0

Insolubles % 0.2 0.4 0.3 0.1 0.2 0.6

TBN 3.3 3.1 3.4 2.4 2.4 2.8




Blackstone Inc Comments:
Did you happen to do some towing over the last 9,246 miles? We only ask because lead came up so much. We often find some excess bearing wear when the engine sees some hard use, but if that's not the case, then maybe we're seeing a temporary particle streak. That might explain why the other metals are still in good shape. A particle streak is when a tiny piece of dirt gouges out some of the lead babbitt, causing lead to read high. Once it passes, it drops down, so this may clear up on its own. The TBN was strong at 3.3, but use 9K miles again and check back.

 

[Nate1979]

There is no way towing such low weight caused that lead unless the oil was shot. I tow all the time in my 5.3 and never see lead.

I would not run it another 9k and hope there isn't an issue. I would take a sample mid-OCI and see if there is an issue.

 

[Chris142]

My wife has gone 2x that milage before I met her.the 5.3 is tough

 

[901Memphis]

It's okay you probably have a couple thousand ppm lead to wear through before it's an issue (just guessing)

 

[bigt61]

Are you towing in OD? That will put more stress on the crank & rods. Try towing in 3rd gear if that's the case. That being said, a 12ft, 3k lb load isn't much. The #'s don't indicate a critical problem yet.

 

[OVERKILL]

Originally Posted By: bigt61
Are you towing in OD? That will put more stress on the crank & rods. Try towing in 3rd gear if that's the case. That being said, a 12ft, 3k lb load isn't much. The #'s don't indicate a critical problem yet.


It's a freakin' truck! It should be able to tow 3K in OD IMHO, I've towed at close to the limit of our Expedition (around 8K, IIRC, it is rated for 8,800lbs) with the selector in drive and it handled it like a boss. A slow boss, but a boss, LOL! Does the manual for this vehicle advise towing in a lower gear?

IMHO this is probably just a particle streak. Some trending will likely show it going back down.

 

[ltslimjim]

I thought perhaps a particle streak as well. Considering the relatively higher levels of Silicon in his UOAs; even though this current one isn't bad for 9k miles, one wonders if he couldn't try to address the Si numbers and see if trending down there would help copper (and Lead subsequently) likewise trend down.

I likewise wonder if perhaps a HDEO might be more practical or a HM oil if the oil is truly doing more work suspending abrasive particles.

Maybe modify your air filtration to have a pre-filter( such as the pantyhose method).

 

[TXHunter]

I was towing in OD. In lots of cases it was up/down hills so it was downshifting into a lower gear anyway. I would not have expected to drop OD for such light weight.

 

[MolaKule]

Look at your silicon levels.

It appears your induction system/air filter is allowing dirt to enter into the engine, increasing wear.

 

[TXHunter]

based on the trends, blackstone believes the silicon is a sealer from work I assume the previous owners did.

 

[ltslimjim]

^That simply isn't the case. You are getting the same rate of ingestion as your first UOA. Look at the rate / 1k miles. It's roughly at least 3 ppm every 1k miles. Worse in other reports.

This could be simply a case of driving in Texas if for no other reason. However, even if previous owners did some work that included a sealer it would have washed out by now. In other words, what work have you done lately?

Hence, the suggestion of inspecting your air intake system and perhaps going with a pre-filter for the dirty side of the air filter. If you can rig it up, a pair of pantyhose is a tried and true method.