: They gave me Dexos instead.....

Smokin' SRX
07-01-11, 02:11 PM
Just had a tranny recalibration done (see nearby thread "Very disappointed".. pages 4 &5) and it really helped! But while they were figuring out which enhancement I wanted, (no, wasn't BLUE!!) they did an oil change.

When all is done I read over the work order pages and see...." Dexos Synthetic Blend oil meets all GM specs and is required on most 2011 and newer GM cars....". So I say
that the oil cap itself has a bright Mobil 1 picture on it! I state that I know Mobil 1 is 100% synthetic and all "blends" are only about 20% synthetic,
and what gives? Service rep says, "it's OK, we use it in the 2011 SRX (GM Free Maintenance Program) with same engine and you'll be fine!". I say " but Synthetic is better in severe cold/hot temps and yields slightly better gas mileage than any other
oil!" He shrugs his shoulders and says next time ask for Mobil 1 if you want it....."

I looked at him in disbelief and decided not to lash into him as these guys usually treat me great for everything and it was a FREE oil change. (negotiated first year free oil when bought!). Work order said .. " $39 oil/filter /top off all fluids/tires." I will pay the extra $ next time as I want the Mobil 1 because we drive maybe 4-6K miles a year and I wait the entire year to change my oil. Don't trust Dexos or any "blend" that long.

Not an apocalypse, they give me great deals here, BUT......... be advised.

Less than happy today.....


07-01-11, 05:48 PM
The new Dexos oil is better than mobil 1. It's a higher graded oil. I use an aftermarket oil thats the same grade as the DEXOS, ie Pennzoil Ultra synthetic. Oh and if you think that MOBIL 1 is 100% pure and not a blend you are very mistaken. :cool:

Smokin' SRX
07-01-11, 11:24 PM
I must disagree on this. I am aware Dexos, a "blended" oil , has special additives, but is not rated as highly as a full synthetic by anyone I'm aware of. Mobil 1 is a full synthetic as per data sheets found everywhere. Here is their site.


Penzoil Ultra is a great full synthetic oil also. I believe it also has Dexos ratings (and a lot more!) I just want the top oils in my engines. A blend is inferior by it's diluted nature and I believe GM has invented Dexos because it is adequate, and conforms to the re-flash of the Oil life Monitor Systems ( I.E. sooner oil changes!) This will save GM money on their FREE Maintenance Program for all 2011 Caddys ,by changing the oil just a little sooner than previous, original OLM settings, but at about 1/2 the product cost. Mobil 1 or almost any full synthetic oil costs much more....

Am I wrong?


Smokin' SRX
07-04-11, 11:03 AM
Anybody?? Really could use some opinions here. The SRX was designed to run with a synthetic to get lube it needs, I thought. Did they put the logo on the oil cap as a marketing deal only??


07-04-11, 01:26 PM
Thanks :)
Learned some stuff.
First Dex-cool - We all know how wonderful that worked out http://www.imcool.com/articles/antifreeze-coolant/dexcool-macs2001.php
and now Dexos
The company sales pitch:
"dexos™ is designed to increase fuel efficiency, extend the life of your emissions system, require fewer oil changes, and produce fewer emissions. You save time and money, and your car performs the way it was designed to."
The other side of coin:

07-04-11, 11:44 PM
What's wrong with Dex Cool? It works just fine. Just don't blend it with any other coolants. :yup:

Smokin' SRX
07-05-11, 12:17 AM
If Dexcool not changed in 3 years it begins to clog the radiator and dissolve eng gaskets. My mechanics all call it dex-kill! When fresh, it seems to work well I must say, but I've been changing in my GM sleds evey 3 years/36K miles.


07-05-11, 07:16 AM
Well, isn't that a given? Though i have an 06 Impala that can prove you wrong. With 240 000 kms, and 5 years, it had its first coolant change just a couple of months ago! She runs like a charm Smokin! :D

Smokin' SRX
07-05-11, 09:47 AM
I know you take care of your rides Capt. Yes, I recall the Owners Manual on my new Yukon also says 5 years/150K miles for changing it. So you hit it spot on! But the complaints are very real and it seems if you let the Dexcool level get even a little bit low , it tends to aerate/foam and somehow thickens or gets very corrosive and eats gaskets/clogs radiators. My mechanic showed me an example of a corroded rad cap. Looked like examples in links above from Amunderdog.

Many caveats against mixing with other coolants OR getting the 50/50 mix wrong too. I play it safe as I want my waterpump/gaskets to live on way past the 5 years/100K warranty.

I hope you flushed yours thoroughly before refilling (I'm sure you did!) That seems to be another caveat....
Stay cool!


07-07-11, 03:21 PM
Funny thing, but I thought the Dexcool issues (clogging, gaskets) were resolved with a reformulation back in the late 1990s.

Second........I won't argue about the theoretical superiority of one lubricant (motor oil, brand) over another. But when following the manufacturers' recommended motor oil (and filter) change intervals and when maintaining the proper motor oil levels, with a name brand product of the correct viscosity, I think few if anyone here can claim they ever had an oil-related engine failure.......while using pure conventional, a blend, or a pure synthetic.

I realize I am a minority of one with my personal experiences, but I don't understand where this discussion is going. I have pushed 3 vehicles past the century mark and have not has so much as an issue with worn piston rings or excessive motor oil usage. The cars ran well until they were swapped for something newer. And I am no featherfoot.


Smokin' SRX
07-07-11, 06:31 PM
PJ, my point was simply that my SRX was said to need full SYNTHETIC oil. (look at the oil at cap on the 2010 series. 2011cap ? Anybody?) It's well documented and hardly theoretical which oil, syntec or standard Dino oil, is superior. Now the Dealer says Dexos, a blended oil, is all I need. It seems odd that this coincides w/ the Free oil changes that GM gives for 4 years on the 2011 Caddys. What about my MPG? Cold/hot extreme protection? And they want to re-flash the Oil Life Monitor in 2010 Equinox and Terrain too, for more frequent intervals now. Maybe syntec is really needed. The Dexos probably will be OK for the first 100K miles if GM Warranty is covering, but after that? I'm gonna stick with full syntec like Mobil 1 or Penzoil Ultra, both Dexos approved by the way.

I too have put over 100K on my GM sleds at times, and yes, they were fine. (one burned noticeable oil after 80K) but none other than this one (SRX) required for full synthetic oil from the factory.

You may be correct on Dexos being re-formulated in late 90's. Don't know. But look at the Nationwide Class Legal action that was settled a couple years ago. There were definite problems for some GM sleds. Engines with low cooling levels particularly suffered. Two good articles below:

1.) http://www.topclassactions.com/close/14-gm-dexcool-engine-coolantOrganic acid technology

2.) Certain cars are built with organic acid technology (OAT) antifreeze (e.g., DEX-COOL[15]), or with a hybrid organic acid technology (HOAT) formulation (e.g., Zerex G-05[16]), both of which are claimed to have an extended service life of five years or 240,000 km (150,000 miles).

DEX-COOL specifically has caused controversy. Litigation has linked it with intake manifold gasket failures in General Motors' (GM's) 3.1L and 3.4L engines, and with other failures in 3.8L and 4.3L engines. Class action lawsuits were registered in several states, and in Canada, to address some of these claims. The first of these to reach a decision was in Missouri where a settlement was announced early in December 2007.[17] Late in March 2008, GM agreed to compensate complainants in the remaining 49 states.[18] GM (Motors Liquidation Company) filed for bankruptcy in 2009, which tied up the outstanding claims until a court determines who gets paid.[19]

According to the DEX-COOL manufacturer, "mixing a 'green' [non-OAT] coolant with DEX-COOL reduces the batch's change interval to 2 years or 30,000 miles, but will otherwise cause no damage to the engine."[20] DEX-COOL antifreeze uses one of two inhibitors: sebacate and 2-EHA (2-ethylhexanoic acid), which works well with the hard water found in the US, but is a plasticizer which can cause gaskets to leak.[14]

According to internal GM documents,[citation needed] the ultimate culprit appears to be operating vehicles for long periods of time with low coolant levels. The low coolant is caused by pressure caps that fail in the open position. (The new caps and recovery bottles were introduced at the same time as DEX-COOL). This exposes hot engine components to air and vapors, causing corrosion and contamination of the coolant with iron oxide particles, which in turn can aggravate the pressure cap problem as contamination holds the caps open permanently.[21]

Honda and Toyota's new extended life coolant use OAT with sebacate as the primary OAT inhibitor, with some phosphates to provide protection while the OAT builds up.[14] Honda specifically excludes 2-EHA from their formulas.

Typically OAT antifreeze contains an orange dye to differentiate it from the conventional glycol-based coolants (green or yellow). Some of the newer OAT coolants claim to be compatible with all types of OAT and glycol-based coolants; these are typically green or yellow in color.

I'm sticking with 3 years 36K miles if my car is a keeper! A leased car, maybe not.


07-08-11, 12:56 PM
I had an 05 Deville that used regular oil. Traded that in for an 08 DTS that used Mobil 1. Exact same engine but I believe the 08 may have gotten fraction more gas mileage to go towards CAFE standards. Now my 11 SRX uses Dexos. As long as it's changed regularly I don't see a problem.

Smokin' SRX
07-09-11, 10:16 PM
I am guilty of waiting for 1 year or 5-6K miles for oil changes. One of the reasons full syntec is for me. I have to assume that Mobile1 one was an insurance policy till newly formulated Dexos came out. Guess it will suffice with reg oil changes. Did you have your OLM system reflashed?? Word is a 25% earlier schedule?....
Thx all


07-10-11, 08:06 AM
I am guilty of waiting for 1 year or 5-6K miles for oil changes. One of the reasons full syntec is for me. I have to assume that Mobile1 one was an insurance policy till newly formulated Dexos came out. Guess it will suffice with reg oil changes. Did you have your OLM system reflashed?? Word is a 25% earlier schedule?....
Thx all


One has to wonder if that is really necessary or if GM is just trying to increase its dealers' profits.

Smokin' SRX
07-10-11, 08:12 PM
One has to wonder if that is really necessary or if GM is just trying to increase its dealers' profits.

Both. Some stories of worn camshaft gears/chains (not sure) have been reported both in SRX and in the new 2010 models Equinox/Terrains also. The early wear is assaulting some owners who linger to change oil apparently..(5% on OLM?) Neither 2010 Nox or Rains require full syntec from factory. But will now get the Dexos blended syntec!

We pay for earlier oil changes/they have less warranty claims? They change oil sooner with Dexos (vs Mobil 1 in SRX) and they have less warranty claims.......with cheaper oil costs?

I'll stay with my Mobil 1 so if I keep her /daughter gets, I should be OK past 5 years/100K warranty. With me I'll have only 25K miles at 5 years and then if engine craps out, I'm toast.


07-10-11, 11:12 PM
Since we only need the oil changed once a year, really not that often according to mileage, I will make sure they use the Mobil 1 when we get it done. Even if it is a few more bucks, I think I can handle that one time a year. We never keep a vehicle 5 years, but if we wer to keep the
SRx taht long, it wold probably have similiar mileage to what you expect.

Smokin' SRX
07-11-11, 11:00 PM
Take a look at this chart:


Dexos seems to be adequate for us, but I will still stay with "best" recco, which is full syntec. Even the V-6's in Equinox and Terrain for 2011 require dexos spec'd oil. The little extra MPG will almost pay the cost difference over a year I figure..


C66 Racing
07-17-11, 09:33 AM
This is going to be an emotional topic for many years to come. Also very hotly debated on the Vette forums where I spend most of my time.

Something to keep in mind is that dexos1 is both GM's new spec for all automotive engines (including the high performance LSx engines like those in the C6 Corvette), and it is also a performance specification. The spec doesn't require a synthetic to meet it and though GM won't say, the general consensus is that GM's branded oil is a synthetic blend.

There are alternatives. Mobil 1 now does meet dexos1 as does AMSOIL's full line (all of which are full synthetics):
AMSOIL Signature Series 100% Synthetic 5w30 (http://www.c66racing-synthetics.com/Product%20Bulletins/ASLPB.htm) (Product Code ASLQT)
AMSOIL XL Synthetic 5w30 (http://www.c66racing-synthetics.com/Product%20Bulletins/XLFPB.htm) (Product Code XLFQT)
AMSOIL OE Synthetic 5w30 (http://www.c66racing-synthetics.com/Product%20Bulletins/OEFPB.htm) (Product Code OEFQT)

Smokin' SRX
07-18-11, 11:45 PM
Yes, oil is always emotional even in politics! LOL

See this site and scroll down to pix of the bottle of oil. SYN Blend for sure. I guess it's good if they put it in ebines they warranty but I'm staying wirh a Dexos FULL syntec as u say like Mobil 1

Thx and end enjoy that Vet!


Smokin' SRX
07-18-11, 11:46 PM
Yes, oil is always emotional, even in politics! LOL

See this site and scroll down to pix of the bottle of oil. SYN Blend for sure. I guess it's good if they put it in engines they warranty but I'm staying with a Dexos FULL syntec as u say like Mobil 1

Thx and enjoy that Vet!


Aurora 5000
03-29-15, 11:52 AM
You should see Youtube pour of oil at -45 degrees, mobil 1 pours a lot quicker than all others... Dexos is a GM Blend. After 1K on new SRX, changed back to Mobil 1 AND Filter. The Local Dealer oil change program gets the car in shop for regular points of inspection, find things wrong, charges GM under warranty, when that expires, You get charged... It's worth it to have a FULL SYN motor oil in your car...cheap insurance, I don't care what brand. Also drain plug is 14mm. Also on Mobil 1 5 qt. bottle at WM, it has dexos symbol on the label. Also is 8$ cheaper. Went to local auto chain for Mobil 1 filter. #212

03-29-15, 12:23 PM
You guys realize that DEXOS is a specification, not a brand, and doesn't specify weather it's a full synthetic, blend, or conventional...right?

There are many oils by many manufacturers that are DEXOS, in full synthetic, synthetic blend, and conventional. Mobil1 is one of them.


If Dexcool not changed in 3 years it begins to clog the radiator and dissolve eng gaskets.Oh, you're one of "them"...

The only difference between DEX and traditional green coolant is that it's silicate free. There is not one instance that a failed gasket can be traced to DEX, or any coolant for that matter.

Clogging? That wasn't the coolant. That was the coolant tablets that GM used to use. They were put in when the car was built, and recommended at service intervals. GM no longer uses or recommends them.

As for mixing, yes, you can mix traditions and DEX, so long as the conventional coolant was designed to be mixed. It will say so on the bottle.

Plenty of myths about coolant, DEX, oil..... Do some actual research before accepting a "mechanics" word as gospel.

Aurora 5000
03-29-15, 12:46 PM
The GM dexos motor oil is developed by Powertrain engineers to the unique specifications and standards seen in all GM vehicles, according to General Motors. GM's is a blend of oil. The Mobil 1 full syn...gold cap..is 100% synthetic, NOT a blend. Also it is dexos approved. Don't believe me, look on the quart container...

03-30-15, 06:59 PM
If you think oil is a political issue here, just mention it on a motorcycle forum. On a motorcycle the oil has to lube the engine, the transmission AND bathe the clutch. People get downright hostile. There are "hot button" issues on this forum too. You will notice I didn't push any of them. Other than being a little "off topic.