Pennzoil HM 10w30, 3k OCI, 86 Cad V8

[ChiTDI]

At 150000 miles test relults were:
Iron 53
Cr 1
Pb 17
Cu 4
Tin 0
Al 9
Nickel 0
Silver 0
Boron 19
Na 66
Potassium 76
Magnesium 24
Calcium 2195
Phosphorous 1090
Zinc 1210
Molybdenum 114
Fuel and glycol Neg, water
Visc@100C cST 11.6
Soot Oxidation 23.00
Nitration 11.40

Lab reports wear levels to be normal, and the slightly high level of sodium could be a slight or intermittent Glycol leak. Antifreeze test was negative.

This car is a daily driver in tough conditions and has had an AutoRx treatment @135k. It needs a TPS and other than that runs like a top.
Change or keep the oil type and OCI?
Thanks for your thoughts.

 

[T-Keith]

Lead seems high. I'd recomend the cooling system tabs, this is the engine they were designed for.

-T

 

[Drew99GT]

How many cooling system tabs do you add?

 

[Brett Miller]

You're definately getting antifreeze in the oil. The sodium and lead are good indicators.

 

[T-Keith]

The recomendation is right on the package, I believe 2 or 3 are usually enough for most systems.

 

[Triple_Se7en]

If it's antifreeze, why the negative lab result? Could Chicago road salt raise the sodium levels or could this be the new Pennzoil-pack with added sodium -- common in alot of SM oils?

 

[ToyotaNSaturn]

The only sodium add I'm aware of is in Exxon-Mobil dino's. I don't believe there is any sodium in the PZ product. Coolant leak IMO.

 

[Bror Jace]

Let's see:

elevated sodium AND potassium.
Elevated (to me, anyways) lead AND iron ...

... classice glycol leak.

Question is, how much do you like this car? If you only plan on keeping it another year or two, or another 10,000-20,000 miles, I'd do the 'tabs' thing and change your oil and filter change to 2,500 miles and use a cheaper oil and filter.

If it means a lot to you, see if you can isolate the glycol leak to head gasket(s) or intake manifiold.

--- Bror Jace

 

[T-Keith]

Bror, I think the reason they developed the tabs for this engines is because replacing a gasket won't fix it. This is an aluminum sleeved engine with iron heads and has several problem areas that don't seal perfectly.

 

[Drew99GT]

Yup, the infamous "porous" Caddy engines.

 

[goodvibes]

I think the Chicago road salt is calcium cloride.

 

[ChiTDI]

The "tabs" are available from the Cadillac dealer I assume?
I like the car for the dependable use it has provided to the younger members of my family.
I'm not enamored with it at $3 a gallon, though.

Thanks for the informed input from all responders, I'll try the tablets, and keep the low OCI with a watchful eye on the coolant.
10k to 20k over the next couple of years would be fine.

 

[ChiTDI]

quote:

---

Originally posted by Drew99GT:
How many cooling system tabs do you add?

---

Caddy dealer told me to use the whole package, after crushing them. There were about eight and they dissolved readily into the antifreeze.
Hope that solves the problem.

 

[twigdog]

Is this the 307 V8 or the 4. something?

 

[ChiTDI]

5.0 Olds 307 V8

 

[ChiTDI]

The tabs seem to be working, and replacing the oil sender switch stopped the oil leak.
Engine has been dry for three months, Go Tabs!!

 

[caprice_2nv]

This is not the engine with the problems they're talking about. You're likely looking at replacing the intake manifold gaskets to cure the coolant leak. This was a common problem on 307's cause of the aluminum intake. Different expansion rates between the aluminum intake and the cast iron heads, puts a lot of stress on the gaskets. The 307 V8 will last a long time if coolant leaks are not ignored.

 

[dave1251]

But even with new gaskets its not going seal completely. That what the tabs are for.

 

[caprice_2nv]

^ Yes it should seal completely. Tabs are just a bandaid. I've spent countless hours on oldspower.com and realoldspower.com. If it's leaking, it needs gaskets. Do not confuse this with the oil burning cadillac engines from the early 80's.