Rotella 5w-40 2785miles '95 Buick LT1

[DJ]

This was my last Oil Guard kit. Car is a 95 Buick Roadmaster wagon.
fe 9
cr 2
pb 11
cu 6
sn 3
al 3
si 3
na 3
k 4
Any elements not listed were zero or not tested.
nitr 0
oxid 5.5
TBN 8.3
visc100 14.5
soot .2

Just before this fill I did a LC flush and added LC at the fill but have been neglectful of the 1K add an ounce

. I ran "'brew" this whole interval as well.
Here are the last two UOAs on the car I did not sample the ARX rinse.
Over 180K on the car at the time of this sample and the warm weather has me enjoying the LT1 torque both of which I think contribute to the numbers not being spectacular but I think they are reasonable

.
This oil is still in the car I am aiming for 5k intervals, without doing a lot of UOAs just want a simple maintenence schedule and wanted to check that this oil seems good for this motor.
I know my OCI goal is concervative but last friday I was drag racing this thing so long OCIs just don't seem like a good goal for me.
Tell me what pops into your head.

 

[Ken4]

Great improvement after the Auto-Rx cleaning phase!

 

[DJ]

Anyone else?
I first tried this in my other LT1 which is modified and it really quieted down the roller rockers even compared to Amsoil 5w30 and 10w-30 which I tried before this in that motor. Once that car is back on the road I might UOA it as well just to see where it is.

 

[Gary Allan]

I wonder how much the visc had to do with the reduction in some of the numbers. You're right, it doesn't seem like extended drains are a thing your gonna have much use for.

I haven't integrated if soot is the same as insolubles.

 

[DJ]

That raised my eyebrow as well I am not sure if that is an oilguard thing or if this diesel oil in a gas motor confused the tech or what

. I am debating sending a sample from this oil to Blackstone a little later on in the interval to see how it compares. Since I think it is mostly Blaclstone numbers we are used to seeing.

 

[Gary Allan]

I have a hard time integrating all the different stuff from lab to lab. I probably haven't really paid attention to results other than Blackstone's since it's what I've used in the past. Some use TAN ..or TBN ..some don't do either and use Oxidation and Nitration ..and may express it in different terms without an index scale (some use % ..some don't

) .


As far as the oil... visc held up well (15.0 is the typical spec) and the TBN is down very little from the 11.5 typical starting point.

From those limited observations, this stuff hasn't even broken a sweat yet.

 

[DJ]

Thank you. On the TBN I saw that too and figured this oil could go quite a while longer based on that. My wear numbers look high after seeing all the GC UOAs but in the grand scheme I think they are OK. I am out of OG kits and Blackstone sent me two after doing my tranny analysis so I have them on hand should I decide to do another UOA.