Importance of HTHS and SAPS?

[budopo]

I've got a 2008 Saab turbo, 87k miles, not burning any oil (well, there's a leak somewhere, but it's very slight, and I don't lose any appreciable oil). The cars used to have a problem with sludge, but that was corrected around 2004 or so.

I know there are a lot of quality oils, but I'd like some opinions about two Amsoil products: European formula AEL and Signature Series ASL, both are 5w30.
The specs for the oils are
Euro
HTHS 3.6
NOACK 7.1
TBN 8.8
Low-SAPS (I think)
Dexos 2, ACEA C3

Signature
HTHS 3.11
NOACK 6.7
TBN 10.1
Dexos 1 Gen 2, ACEA A5/B5
Don't know the SAPS, but the sheet says "fortified with detergents that exceed the Dexos 1 Gen 2 sulfated ash specification", which sounds to me like it's low-SAPS with other additives to replace the low sulfated ash.

The Signature Series looks better, except that the HTHS is quite a bit lower than the European formula. The TBN seems pretty high, and I wonder how it holds up over time. I have a couple of questions:
Is the 3.11 HTHS sufficient, or woudl 3.6 be better? I don't race the car, but it is tuned for a little more output (there's also some high acceleration for passing, stop-and-go traffic, and long road trips).

Is low-SAPS vs mid-SAPS something I should consider, or is it not really critical? Would the Signature Series' "fortified detergents" be any better than the Euro low-SAPS?

I'm old school, so change the oil every 5,000 miles (give or take), so the TBN isn't too much of a concern. The sump is near the catalytic and can get hot, so is a differnece in NOACK of 7.1 vs 6.7 significant (the car has an oil cooler)?

Thanks in advance.

 

[FCD]

For your Turbo Saab i think lower NOACK and higher HTHS would be the way to go.

 

[kschachn]

Just be aware that neither one of those oils actually have the certifications you list. Especially given the short OCI you do (which I don't disagree with in this application) a much less expensive alternative would be Castrol 0W-40 available at Walmart for $23/5 quarts. It actually has A3/B4, Porsche A40 and BMW Longlife-01 specs and would perform equally well in your engine.

HTHS is critical in this application and a high SAPS is desirable.

 

[benjy]

Amsoil has "gone away" from their PAO + Ester formulations + say only they meet the spec, so read between the lines!!! in Pa i use mobil I extended performance 10-30 said to add some PAO in my 2001 TT 1.8T about 275 hp + 300 tq + change yearly as its a summer fun car. with your shorter intervals this would be a good choice IMO. a 10W is good enough for winter as i use the same in my winter ride a 2011 nissan frontier SV, a 5W starts as a 5Wxx where as a 10Wxx requiring less viscosity improvers for optimal protection an Ester based oil like Redline is better but $$$$$. lots of choices depending on your needs + the $$$$. real synthetics PAO + Ester need NO viscosity improvers for a 10W30 as the 30W meets the 10W spec without those additives!!

 

[StevieC]

As a happy Amsoil user for almost 2 decades I would definitely use the Euro in your Saab.

 

[StevieC]

Originally Posted By: benjy
Amsoil has "gone away" from their PAO + Ester formulations + say only they meet the spec, so read between the lines!!!

Proof of this?

Also Redline isn't the "Ester" oil it used to be. The formula has changed since the good old days.

 

[1JZ_E46]

I wouldn't focus on SAPS content for a car like yours. Both of those oils are low/mid SAPS. HTHS of 3.5+ is what you're after. Why spend that much coin on Amsoil? Something like Rotella Multi-Vehicle 5W-30, Castrol EDGE 0W-40, or Mobil 1 High Mileage 10W-30 are very good HTHS 3.5+ oils at a good price.

 

[ka9mnx]

Originally Posted By: kschachn
Just be aware that neither one of those oils actually have the certifications you list. Especially given the short OCI you do (which I don't disagree with in this application) a much less expensive alternative would be Castrol 0W-40 available at Walmart for $23/5 quarts. It actually has A3/B4, Porsche A40 and BMW Longlife-01 specs and would perform equally well in your engine.

HTHS is critical in this application and a high SAPS is desirable.


^^^THIS. Also NOACK is on the very low side. My issue with Amsoil is price and availability...

 

[budopo]

Thanks everyone for the replies. I'll look into the other oils recommended. I don't put a lot of miles on the car, so while cost is always a factor, it's not too critical for me. Of course, if I can get equal or better oils for less, so much the better.

What I gather from the responses is that HTHS is what's critical, with NOACK 2nd, and mid-SAPS is good, but not critical. I'll look at Castrol, Mobil 1, and Redline. I'm sure they'll all be fine (also Amsoil Euro) for my car. It's just a matter of which is best.

 

[Gokhan]

This car specs A1/B1 or A5/B5 5W-30, right? If that's the case, you don't need high HTHSV.

Go with Amsoil Signature Series ASL 5W-30. It has a mostly PAO base oil (BOQI = 75) as opposed to the mostly Group III base oil (BOQI = 47) of Amsoil European AEL. It also has a higher TBN. These two properties in combination mean that you can do a lot longer OCI with ASL. On top of that, you get dexos1 Gen 2 (Ca/Mg detergent), something European AEL doesn't have. AEL has less VII than ASL though but ASL is still good (A_Harman index = 0.97 for AEL vs. 0.93 for ASL).

Amsoil SS is simply a far better oil than Amsoil European (PAO vs. Group III, respectively) unless you need high HTHSV or low SAPS, which you don't. You're getting Amsoil instead of a light-gray or yellow jug from Walmart as most people on this blog do; so, why not get their best oil?

Alternatively, any dexos1 Gen 2 5w-30 should be a good oil for this car.

 

[budopo]

Actually, the car calls for GM-LL-A-025. I forgot to put that in the original post. The Signature Series looks pretty good, aside from the lower HTHS. The TBN isn't too much of a concern, since I change the oil at 5,000 miles or so.

Is there much difference between Dexos1 Gen 2 (Signature Series) and Dexos 2 (Euro oil)? I know Dexos 2 is for diesel and petrol engines, but is there much difference between the two for a European turbo petrol engine?

 

[Gokhan]

Originally Posted By: budopo
Actually, the car calls for GM-LL-A-025. I forgot to put that in the original post. The Signature Series looks pretty good, aside from the lower HTHS. The TBN isn't too much of a concern, since I change the oil at 5,000 miles or so.

Is there much difference between Dexos1 Gen 2 (Signature Series) and Dexos 2 (Euro oil)? I know Dexos 2 is for diesel and petrol engines, but is there much difference between the two for a European turbo petrol engine?

Oh, OK, GM-LL-A-025 is dexos2 now. So, go with dexos2 if that's the case.

Yes, dexos1 and dexos2 are entirely different -- low-HTHSV and mid-SAPS vs. high-HTHSV and low-SAPS, respectively.

Mobil 1 is starting to sell dexos2 -- Mobil 1 ESP 0W-40.

Amsoil AEL is a good dexos2 choice.

Pennzoil Platinum Euro L dexos2 5W-30 is already cheaply available at Walmart.

 

[kschachn]

Originally Posted By: Gokhan
Amsoil AEL is a good dexos2 choice.

Except for the fact that it isn't dexos licensed.

 

[JAG]

You can make a blend of Amsoil SS 0W-40 and 5W-30 at a ratio that gives you the desired HTHS viscosity. I’d shoot for 3.5 to 3.7 cP. 60% to 65% of 0W-40 in the mix would do the trick. https://www.amsoil.com/lit/databulletins/g2880.pdf

 

[kschachn]

Originally Posted By: Gokhan
Go with Amsoil Signature Series ASL 5W-30. It has a mostly PAO base oil (BOQI = 75) as opposed to the mostly Group III base oil (BOQI = 47) of Amsoil European AEL. It also has a higher TBN. These two properties in combination mean that you can do a lot longer OCI with ASL. On top of that, you get dexos1 Gen 2 (Ca/Mg detergent), something European AEL doesn't have. AEL has less VII than ASL though but ASL is still good (A_Harman index = 0.97 for AEL vs. 0.93 for ASL).

Or just go to Walmart and buy Castrol 0W-40 @ $23 for 5 quarts and have an oil that is also majority PAO, and carries some of the most stringent manufacturer approvals in existence.

 

[1JZ_E46]

Clan we stop with the BOQI already. It’s a made-up metric.

 

[Gokhan]

Originally Posted By: kschachn
Or just go to Walmart and buy Castrol 0W-40 @ $23 for 5 quarts and have an oil that is also majority PAO, and carries some of the most stringent manufacturer approvals in existence.

OP later said that the spec was GM-LL-A-025. I would therefore go with a dexos2 oil instead of an ACEA A3/B4 oil because GM-LL-A-025 is now dexos2. Pennzoil Euro L dexos2 5W-30 is cheaply available at Walmart.

 

[1JZ_E46]

I just posted a UOA of Castrol Edge 0W-40 in my BMW. Stellar results as usual. PP Euro L is also good stuff, just not as widely used as Edge 0W-40... less UOAs of it to browse. Either will suit your Saab well.