AMSOIL 5-w30 for 7.5k (changed once) i think its great stuff. They have a new 0-w30 which is supposed to be the cutting edge. Expensive, but worth it if it burns more slowly than conventional oil.

 

Been using Amsoil since my first car(Acura TSX), and it's great!

 

Care to elaborate beyond "it's great"?

How is fuel mileage? Sound of the engine? Smoothness?

 

I wonder if there can be that much more chemistry put into Amsoil over any other name brand synthetic? Plus with the multi-level marketing distribution channel, isn't the price inflated by the commissions paid to the different middle men?

Personally I avoid anything sold via MLM schemes. Oil from Costco or Walmart is fine by me.

 

1. All the oils were 10w30 viscosity
2. The oils tested were:
Amsoil (syn)
Castrol GTX Drive Hard (mineral)
Valvoline Synpower (syn)
Mobil Drive Clean (min)
Pennzoil Purebase (min)
Quaker State (Syn)
Quaker State Peak Perf (min)
Castrol Syntec (syn)
Valvoline (min)
Pennzoil Synthetic (syn)
Mobil1 SuperSyn (syn)

The following ASTM tests were run:
Thin-film Oxygen Uptake ( D-4742)
High Temp/High Shear ( D-4683)
NOACK Volatility ( D-5900)
Pout Point (D-97)
Total Base Number (D-2896)
Cold Cranking Simulator D-5293)
4-Ball Wear (D-4172)
************************************************** *******
Test 1: Thin Film Oxygen Uptake:
Measures the oxidation stability of an oil.
The induction time (break point) in minutes is measured. The test uses standard amounts of fuel dilution, soluble metals, and water to offer a real-world applicability.

Results for this test(all units in minutes):
Amsoil: >500 (no break)
Mobil1: 397
Pennzoil Purebase: 242
Castrol Syntec: 221
Valvoline: 219
Vavoline SynPower: 211
Mobil Drive Clean: 209
Quaker State Peak Performance: 192
Pennzoil Synthetic: 159
Quaker State Synthetic: 159
Castrol GTX Drive Hard: 132

Test 2: High Temperature/High Shear (HT/HS)
Measures a lube's performance under severe heat and shear (mechanical stress) as would be found in the journal bearings under heavy load. The units displayed are viscosity based, using the centipose unit (cP). The minimum spec for a 30w is 2.9 cP.

Results for this test (all units in cP):
Amsoil: 3.51
Quaker State Peak Performance: 3.37
Castrol GTX Drive Hard: 3.35
Vavoline SynPower: 3.30
Mobil1: 3.30
Valvoline: 3.30
Mobil Drive Clean: 3.28
Pennzoil Purebase: 3.16
Quaker State Synthetic: 3.15
Pennzoil Synthetic: 3.14
Castrol Syntec: 3.13

Test 3: NOACK Volatility.
Measures the evaporative loss of lubricants in high temperature conditions. The higher the number, the thicker the lubricant will become. API SL and GF-3 specs allow for a 15% evaporation limit. In this test, obviously, lower is better. Syns almost always have an advantage due to their monomolecularity.

Results for this test (% weight loss):
Amsoil: 4.86
Vavoline SynPower: 7.03
Castrol Syntec: 7.77
Quaker State Synthetic: 7.80
Pennzoil Synthetic: 8.15
Mobil1: 8.92
Castrol GTX Drive Hard: 8.93
Quaker State Peak Performance: 10.63
Mobil Drive Clean: 10.83
Pennzoil Purebase: 10.93
Valvoline: 12.18

Test 4: Pour Point
This test reveals the lowest temperature at which a lubricant will flow when cooled under test conditions. The lower, the better the product will perform in getting from the oil pan to the upper oil galleys, and in providing oil pressure quickly. Synoils generally are the best, because they are free of wax crystals, but today's mineral oils are better refined to remove wax impurities, and use advanced pour point depressant additives to help offset the synoils' intrinsically better properties.

Results for this test (all units in degrees Centigrade):
Amsoil: -48
Mobil1: -46
Vavoline SynPower: -46
Castrol Syntec: -43
Pennzoil Synthetic: -40
Quaker State Synthetic: -40
Pennzoil Purebase: -37
Valvoline: -37
Mobil Drive Clean: -37
Castrol GTX Drive Hard: -37
Quaker State Peak Performance: -34

Test 5: Total Base Number (TBN)
TBN displays the lubricant's reserve alkalinity, and is, of course, the opposite of TAN (total acid number). A high TBN will help resist the formation of acids from sulfur and other sources. It is also a good indicator of reserve resistance to oxidation. The higher the number, the superior ability to suspend contaminants and the greater the ability to provide long-drain intervals
Results for this test (all units in mg KOH/g):
Amsoil: 12.34
Vavoline SynPower: 11.38
Castrol Syntec: 10.39
Pennzoil Synthetic: 9.73
Mobil1: 8.57
Valvoline: 7.88
Quaker State Synthetic: 7.82
Castrol GTX Drive Hard: 7.74
Mobil Drive Clean: 7.71
Quaker State Peak Performance: 7.55
Pennzoil Purebase: 7.40

RR's comments: I was very impressed with all the oils, as the mineral oils have significantly improved, consistent with previous comments about how mineral oils are closing in, and that the GF-3 spec has resulted in very good performing products. Mobil1's showing is the best i have seen for that product, which usually was in the 5-6 range previously. It certainly also supports my previous comments that the 3K oil change "necessity" is out of place with current technology. Like an enema for a dead man, while it may not help to do a 3K change, it wouldn't hurt I guess.

Test 6: Cold Crank Sumulator
This one determines the apparent viscosity of the oils at low temperatures and high shear rates, simulating the dreaded cold start. It has direct applicability to engine cranking, the lower the number the better in terms of stress on the battery, starter, etc. A 10w is tested at -25degF and must show a vis <7000 cP to pass.

Results for this test (all units cP at -25degC):
Pennzoil Synthetic: 3538
Amsoil: 3590
Mobil1: 3967
Quaker State Synthetic: 4142
Vavoline SynPower: 4541
Quaker State Peak Performance: 4620
Castrol Syntec: 4783
Castrol GTX Drive Hard: 5804
Pennzoil Purebase: 5936
Mobil Drive Clean: 6448
Valvoline: 6458

RR Comments: If you live and drive your car in very cold climates, the advantage of the synoils is obvious. Keep in mind that the NOACK performance figures here as well, as this tests hows the performance of fresh oil - after a few thousand miles, the oils with higher volatility will likely have thickened, unless there has been high dilution from fuel, such as can occur if excessive startup idling warmups are employed.


Test 7: Four Ball Wear
This one is a good indicator of the wear protection of a lubricant, although in the real-world it is should be factored in with the TBN of the oil. Three metal balls are clamped together, and a rotating 4th one is pressed against them in sliding contact. A scar is produced, since at some point the film strength (resistance to being squeezed out) of the oil will be exceeded. The scar is then measured, and the smaller the average wear scar, the better. This test is affected by both the base stock of the oil, and its additive package.

Results for this test (all units in inches):
Amsoil: 0.40
Castrol Syntec: 0.45
Vavoline SynPower: 0.55
Quaker State Synthetic: 0.55
Mobil Drive Clean: 0.55
Pennzoil Synthetic: 0.60
Mobil1: 0.60
Valvoline: 0.60
Castrol GTX Drive Hard: 0.60
Quaker State Peak Performance: 0.60
Pennzoil Purebase: 0.65

 

Also, you can order Amsoil direct from their website and the price isn't bad

 

Amazing that only one person thus far has noticed this thread was started NINE YEARS ago.

Even more amazing? Amsoil was $4 a qt. in 2002.

 

I bought an 02 S2K with 39,000 KM on it last April. The previous owner only used MOBIL 1 in the car since new. I did an oil change last yr using the Mobil 1 again, however, after reading all the good reviews on the Amsoil, I think I'm gonna give it a shot this yr. Should I stick to the regular synthetic 10w30?

 

10W-30 is perfectly good for the S2000. I used 10W-40 in my 2001 S2k for 8 years I liked it because you can buy 2.5 gallon containers for a little less $ but also use the emptys for putting used oil in for recycling.

The S2000 manual for my 2001 indicated that 10W-40 is good but latest MPG requirements have made most manuf's recommend 10W-30 or lighter even though 10W-40 will not hurt any cars that I know of. However in Canada I suspect that lighter oils are better, especially for winter use.

Now I use their latest formulation of 0W-30 which is a little more $ but it is perhaps their best oil and for the S2k is what it deserves.

If you want to still change oil at 7500 mi. or less you can use their partial synthetic (XL style).

If you go to their web site (www.amsoil.com) you can search for your car and see the full recommendation of engine oil, trans and diff lube and Amsoil Filter. I strongly suggest buying their EaO filter. Amsoil has always had great filters, I suspect you cannot buy any better.

Go to the Amsoil website and search for G1490 (publication) it gives the a general guide of how long to use various Amsoils for what and which cars are prone to sludge which is a no-no for extending intervals much.

 

gbaker, thanks for your reply. I'll look at there website and go from there. Thanks budd.
Nelson