maybe this is already known, but for the past week, after i changed the oil with mobil oil (regular non-synth), i was getting average 10-15 mpg. now the ONLY reason i used mobil is because i did not want to use synthetics (i'm at 3500 right now) and castrol's (my preferred oil for reg. motor oil) regular oil does not come in 5w-30 (or maybe it does but i did not see it). after much irritation, i switched after 300 miles to castrol syntec blend. it's not plain motor oil and it's not fully synthetic, so i felt a bit more comfortable. after starting up the, the car sounds much better and i'm filling her up tonite so we'll see how she does on mpg since i'm heading up to boston this weekend to visit my sister.
talking to the guy at R&S Strauss, he told me of many customers complaining about how mobil's regular motor oil gave them bad mpg, so i wasn't the only one. thank god for that. anyone have castrol syntec blend and have any opinions on it.
i'm gonna stick to this oil for about 3-3500 (so around 6500-7000 on the odometer) and then switch over to fully synth. okay...just cross my fingers and hope the oil was the mpg issue.

for now, peeeeeeeeace....

 

Read the spreadsheet at the top of the general forum. That pretty much explains why the Castrol blend is a waste of money. The conventional Mobil is a Group 1 basestock (cheap), so I'm not surprised people are having bad experiences with it.

 

really?


Empirically, the Mobil 1 Drive Clean conventional oil is better than Castrol Syntec.


Castrol Syntec Blend is probably the second worst empirical baseline oil I have seen next to Valvoline's "All Climate" conventional oil. Syntec Blend is probably the worst oil for the buck.



Castrol GTX comes in a 5W/30. I see it everywhere.



I would get the Syntec Blend out of the car as well. Castrol GTX can be found at Pep Boys, AutoZone, Sears, K-Mart, Target, Advance Auto, etc.

 

Geez, even if the Mobil petro oil is cheap, how the heck would it make him go to 10-15 mpg?

I get 21 around town, high 19s if I'm jumping on it a bit.

PoLo, you don't have to floor it on every acceleration.

Are you leaving the car running a lot?

10-15mpg, you got some big problems.

 

DUDE~!! i have the regular mobil in my car and it seems fione

 

DUDE~!! i have the regular mobil in my car and it seems fione my shifts seem to be laggin though....it holds the gear a while longer....im switching from valvoline.....oh ****.....wait...my mistake.... i have valvoline in my car....cheap stuff...but its all good...ur car cannot go 10 - 15 miles just cuz u change the oil...you probably pressing the accelerator a little harder or you did some mod that would help decrease the mpg.

 

Amsoil is the best!!!

 

I used Mobil Drive Clean 5w30 for 3k miles in my 2k2 and it averaged 20 mpg.

Castrol GTX does come in 5w30 weight; look for the white cap.

 

other issues at play... I dont think oil would account for 5mpg (or 25% loss). You could have a MAF or coil problem, very likely.

The VQ is so damn loud when its not getting proper oiling, you could almost diagnose that problem by ear at 30 ft from the car. She wont just sit idly by and not let you know me thinks.

I really wouldnt worry right now about the oil I was running, but I would definately get something better in it before temp outside starts dropping (and I'm assuming youre somewhere thats not super hot anymore).

 

well for now i'm sticking to the syntec blend. after my trip to boston, we'll see what happens. i just drove it for like half hour, and even though that mpg-monitor ain't so accurate, it read 20. who knows...i don't even drive the car anymore cause i work in the city. today was the first time i drove her in a week.

first impressions though is that she does idle much smoother and pick up is also smoother. yeah, maybe castrols syntec isn't the favorite choice, but i don't think it'll break my engine. all i'm lookin for is anything to let me live till i hit the 6-7k mark, after which i will go synth. so as long as i can still drive, then i'm happy.

 

just listen for tick on startup, thats where your bad wear potential would occur. just change it out like it was a dino oil.

 

I don't think the oil itself will cause a 25% loss, but it could easily account for a few %. Combine that with a normal variation in driving style for each day, and you could easily see the 25% difference.

 

well i'm in boston right now....total miles driven so far, 225 and i'm a tad below the halfway mark. tripometer has calculated 26.9mpg and i still have 100 miles left. looks like i needed a long trip to open up this engine. i'm happy once again and the car is perfect. when i drain these miles tomorow i'll have calculated my exact mpg.
ok, now to look for a boston bar...peace

 

Yeah, I've been using 5W-30 Mobil Drive Clean and it seems fine to me too. I haven't noticed a change in mpg. On sale for $.99/quart, it's pretty cheap. I usually buy a whole case.