Over 60mpg on T6 5w40

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Looking back at my archives I’ve exceeded 60mpg on a tank in warm weather low speed town situations with my 5mt beater Cobalt several times (hand calculated)
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Hyper milling and low speed warm weather

My car seems to destroy oil at about 1500 miles so I’ve went with T6-5w40, good gas mpg and the car doesn’t get super noisy at 1500 miles but now it appears I’ve lost a half quart in 1500 miles which isn’t normal

I’m considering pp 10w30 though I didn’t notice consumption with Amsoil 0w40 either

Curious what oil would you use on a car that GM screwed up the timing chain replacement on that is just gonna be run into the ground without repairs?
 
Oh no that's not possible because EPA says so. :LOL: 🍭

I'd decide if I thought a better oil would prolong its life any. I'd probably conclude that it won't, and use the cheapest oil I could find. I mean you make it sound like the car is going to fail long before it "wears out" per say. Cheapest, lowest W grade 40 I could find?
 
What engine is in your Chevrolet Cobalt?
Why use expensive synthetics in a beater car? I would try an inexpensive HDEO like Supertech/Mobil/Delo 15w-40 if the timing chain has issues that you would like to prolong the life of.
 
What engine is in your Chevrolet Cobalt?
Why use expensive synthetics in a beater car? I would try an inexpensive HDEO like Supertech/Mobil/Delo 15w-40 if the timing chain has issues that you would like to prolong the life of.
The chain is as yet fine but seals and water pump were likely botched allowing an infinitesimally small amount of coolant to get into the oil, takes a year before I have to add but my oil turns into whipped cream

The 10w30 synthetic I bought was $3/5q so price is a non issue

I end up changing the oil every 1500 miles on Dino but synthetic I can make it to 3000 without immense horrifying noise, filter looks crushed and destroyed on Dino at 1500 miles, synthetic it looks much less nasty.

Car sounds like new to about 1500 miles on most oils but I like not having to change it constantly , 3000 miles is bad enough, if this $10/gallon T6 makes it 5000 with top offs I can live with it, though I rather not have a drinker if the 30w stays full
 
how low speed we talking
Due to training I had a month of 15 mile one way 25mph city surface streets due to the locations in each city it didn’t make sense to drive 15 miles out of my way to hit highway and the streets were mostly unoccupied back roads that go mostly unused allowing for hypermiling, the series of 7 roundabouts didn’t hurt (most of the time) keeping the tiller straight:)

My top speed in the rural stretch was 45/50 but most was coasting at low speeds

It is extraordinarily rare I get to take things leasurely in terms of speed but even at 70/75 I seem to stay 40/44mpg, during the high fuel prices when I bought the car I kept it at 50mpg average for years by driving back highways with mostly 45mph limits,
Saved lots of money over the 37mpg rating during the last bout of $4ish fuel
And you can NEVER come close to that in the automatic versions of cars.


I posted the way I did because of this thread

Which I found to be hilarious , my antique beater at slow speeds can be Prius like (when driving extremely carefully)
 
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Due to training I had a month of 15 mile one way 25mph city surface streets due to the locations in each city it didn’t make sense to drive 15 miles out of my way to hit highway and the streets were mostly unoccupied back roads that go mostly unused allowing for hypermiling, the series of 7 roundabouts didn’t hurt (most of the time) keeping the tiller straight:)

My top speed in the rural stretch was 45/50 but most was coasting at low speeds

It is extraordinarily rare I get to take things leasurely in terms of speed but even at 70/75 I seem to stay 40/44mpg, during the high fuel prices when I bought the car I kept it at 50mpg average for years by driving back highways with mostly 45mph limits,
Saved lots of money over the 37mpg rating during the last bout of $4ish fuel
And you can NEVER come close to that in the automatic versions of cars.


I posted the way I did because of this thread

Which I found to be hilarious , my antique beater at slow speeds can be Prius like (when driving extremely carefully)

You must have monk-like patience.

I have a manual Scion Tc, pretty comparable to a manual cobalt in a general sense. In terms of compact cars its kind of a pig, 2.4l engine and about 3000lbs, but I get approx 28-30mpg most tanks driving very throttle happy and doing 80-85 on the highway. I mostly attribute this to timing lights and using the brakes as little as possible, which is easy to do if you know the route well and have a manual trans. This got me thinking I should try hyper milling for a tank just to see how many miles I could get, but I highly doubt I would have the patience lol.
 
In certain areas along my twice weekly 100 mile trip there are officers that state the limit is the limit and pull you over if your 1mph fast to ticket

I do speed but I try to regulate it as insurance and fines become extreme if you get pulled over, just not worth a few minutes savings
 
T6 is likely a much more robust oil than any of the other choices. It has an excellent HTHS, and while I don't put stock in UOA "wear metal numbers" T6 consistently provides class leading numbers.
 
Looking back at my archives I’ve exceeded 60mpg on a tank in warm weather low speed town situations with my 5mt beater Cobalt several times (hand calculated)
View attachment 98766

Hyper milling and low speed warm weather

My car seems to destroy oil at about 1500 miles so I’ve went with T6-5w40, good gas mpg and the car doesn’t get super noisy at 1500 miles but now it appears I’ve lost a half quart in 1500 miles which isn’t normal
...

If you are truly "hypermiling", how could your GM 2.0L "destroy oil" at 1,500 miles? Asking for a friend....

So you are driving at low speeds on extended jaunts but still need a 40W oil? Okay....
 
If you are truly "hypermiling", how could your GM 2.0L "destroy oil" at 1,500 miles? Asking for a friend....
In certain areas along my twice weekly 100 mile trip there are officers that state the limit is the limit and pull you over if your 1mph fast to ticket

I do speed but I try to regulate it as insurance and fines become extreme if you get pulled over, just not worth a few minutes savings
:rolleyes::cautious:
11902499_10153494721627332_5311788519161547242_n.jpg
 
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Drive the same car basically, 09 G5 auto 2.2. On my all-highway commute, my readout fluctuates usually between 33 to 39mpg while driving; and my average mpg is about 31.
I have the same issue you do - car runs great, uses NO oil at all, but every few starts I get brief but loud timing chain rattle.
So, the tensioner is going south, but I am not going to put the $$ into replacing it on a rusty 160k-mile beater. Will drive until it quits.
I just do relatively short 5-6k oil changes, where the OLM would push it to over 10k. I just use whatever quality 5W-30 is a deal, be it bulk at my garage, or something else. I have noticed as I get closer to 5k; the noisy starts do become more frequent. I’ve been tempted to try a 40-weight, but just haven’t yet. I’ve tried STP syn oil treatment, and it had the same effect that ‘wore off’.
 
Looking back at my archives I’ve exceeded 60mpg on a tank in warm weather low speed town situations with my 5mt beater Cobalt several times (hand calculated)
View attachment 98766

Hyper milling and low speed warm weather

My car seems to destroy oil at about 1500 miles so I’ve went with T6-5w40, good gas mpg and the car doesn’t get super noisy at 1500 miles but now it appears I’ve lost a half quart in 1500 miles which isn’t normal

I’m considering pp 10w30 though I didn’t notice consumption with Amsoil 0w40 either

Curious what oil would you use on a car that GM screwed up the timing chain replacement on that is just gonna be run into the ground without repairs?
You don't have regenerative braking, engine stop, a high-efficiency Atkinson-cycle engine, low drag coefficient, not to mention that your engine is old and out-of-tune and you run a very thick HDEO, and yet you get brand-new-Prius-like efficiency. I wonder if your odometer calibration is way off. Also, you need to fill at the same pump every time and at the same position to get an accurate gallons reading. Over 60 mpg would give you over 800 miles on a tank, and I find that hard to believe even for extreme hypermiling. EPA rating is only 29 mpg, whereas like 55 mpg for Prius.
 

If your ever in Weyewega try speeding, lots of stories about “that guy”

3 times of being pulled over with said line by Waupaca and Weyewega was enough for me, don’t get highway tickets anymore.

In the same area My mom got pulled over for not slowing down enough (she was under the limit)
while an officer had someone else pulled over and got a repair ticket for her license plate because the number wasn’t in the lower rh corner (pile of years of stickers and my father started placing them in different spots so they would stick)

You don't have regenerative braking, engine stop, a high-efficiency Atkinson-cycle engine, low drag coefficient, not to mention that your engine is old and out-of-tune and you run a very thick HDEO, and yet you get brand-new-Prius-like efficiency. I wonder if your odometer calibration is way off. Also, you need to fill at the same pump every time and same position to get an accurate gallons reading. Over 60 mpg would give you over 800 miles on a tank, and I find that hard to believe. EPA rating is only 29 mpg, whereas like 55 mpg for Prius.
Nope, my odometer usually underestimates my distance about 0.5 miles on a hundred per my gps

I know how to drive a stick, I have 48psi in my 52psi rated energy savers
And my Prius like efficiency is at low speeds, with lots of 99.9mpg coasting.
a Prius would beat me MPG wise going normal speeds with normal driving.
Said car has never shown any change in fuel economy because of oil, my father put synthetic 0w20 in it once because he had too much of it and besides sounding like hammer and rattle time my gas mileage seemed identical

Anyone with a manual can EOC, DWL, or P&G

If you don’t know how to drive efficiently I recommend visiting cleanmpg or ecomodder
The tricks I use pretty much won’t work on an automatic, which is why I no longer own them
(Years ago, I had access to both a 5mt and Auto cobalt, in cold weather on my short work trip I couldn’t break 16mpg on the auto cobalt while my 5mt car would get in the 40’s on the same trip in 20 below, glad that car went away, completely different car stick to auto)

I’m pretty good at hypermiling but not to the level of Wayne Gerdes and anymore don’t have the time or the roads to do it on. Was glad to see my old car could still get good fuel economy with the right conditions, I almost thought it couldn’t do so but nowadays I just basically drive the car.

Driving similarly I have hit a tad over 100mpg when I was driving my old Insight .
Understanding how and when your engine outputs the best economy using a scan gage is important to starting to understand how changes to your tires, pressure, shift points and driving technique can affect your efficiency in a big way.

I almost ended up in a fuel economy competition during engineering college so I’m no stranger to the subject, I was hypermiling before there was such a thing, my father kept a vacuum gage on his Yugo to better MPGs.

Most folks don’t concentrate and pay attention to gages, my same cobalt if I use run flats at the door sticker pressure drops my gas MPGs 10+ without changing anything else. Lots of little things make a big difference, when I was stuck in traffic on the highway I could usually break 50mpg motor off moving 5mph.
Hypermiling works best in extremely boring slow traffic to keep your mind from wandering
 
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If your ever in Weyewega try speeding, lots of stories about “that guy”

3 times of being pulled over with said line by Waupaca and Weyewega was enough for me, don’t get highway tickets anymore.

In the same area My mom got pulled over for not slowing down enough (she was under the limit)
while an officer had someone else pulled over and got a repair ticket for her license plate because the number wasn’t in the lower rh corner (pile of years of stickers and my father started placing them in different spots)
Whatever dude. I've had two cars with that engine and you ain't getting 74mpg if you add an electric motor, a sail, and a solar panel and drive downhill all day...


GM made the AFE Cobalt in around 2008 or '09 and the highway was great at 37mpg. That's not to say one can't do better, but you are just trolling here...
 
You don't have regenerative braking, engine stop, a high-efficiency Atkinson-cycle engine, low drag coefficient, not to mention that your engine is old and out-of-tune and you run a very thick HDEO, and yet you get brand-new-Prius-like efficiency. I wonder if your odometer calibration is way off. Also, you need to fill at the same pump every time and at the same position to get an accurate gallons reading. Over 60 mpg would give you over 800 miles on a tank, and I find that hard to believe even for extreme hypermiling. EPA rating is only 29 mpg, whereas like 55 mpg for Prius.
All your technology is missing the loose nut behind the wheel... 60mpg in low speed rural driving is possible in a manual Cobalt, just takes a bit of time rolling around with the trans in neutral, a bit of lugging, and more time coasting to stops than braking. For sure in a normal flat 55mph highway trip, with only a few stops a Cobalt won't get 60mpg. If you add in some rolling hills though, then you could have a situation where you could do 1/4 of a trip with the engine idling or off depending on how adventurous the driver is. All manual trans cars can be a gravitational potential energy hybrid if the driver wants and the terrain is suitable.
 
All your technology is missing the loose nut behind the wheel... 60mpg in low speed rural driving is possible in a manual Cobalt, just takes a bit of time rolling around with the trans in neutral, a bit of lugging, and more time coasting to stops than braking. For sure in a normal flat 55mph highway trip, with only a few stops a Cobalt won't get 60mpg. If you add in some rolling hills though, then you could have a situation where you could do 1/4 of a trip with the engine idling or off depending on how adventurous the driver is. All manual trans cars can be a gravitational potential energy hybrid if the driver wants and the terrain is suitable.
Well, you get ∞ mpg going downhill with the transmission in neutral and engine off, but you need to look at the round-trip mpg for it to be meaningful.

With my 2021 Prius Prime, I can do 75 mpg round-trip with hypermiling in warm weather, perhaps 80 mpg with extreme hypermiling. I can do over 100 mpg in freeway stop-and-go traffic, but that's only because the ICE is off most of the time, and you are using regenerative braking with the motor–generators while crawling through the traffic mostly in EV mode. These days, without hypermiling but driving gently, I average around 65 mpg. It will probably be 70 mpg when the weather gets hot, which makes the air thinner and less humid, decreasing the drag.

I would believe perhaps close to 50 mpg with extreme hypermiling with the Cobalt. You need to make sure that your odometer is calibrated correctly, you are filling at the same pump, and you are looking at the round-trip mpg—because it is easy to cheat the mpg figures.
 
Whatever dude. I've had two cars with that engine and you ain't getting 74mpg if you add an electric motor, a sail, and a solar panel and drive downhill all day...


GM made the AFE Cobalt in around 2008 or '09 and the highway was great at 37mpg. That's not to say one can't do better, but you are just trolling here...

I meant XFE Cobalt. It was made during the fuel prices of 2008 and was rated 26 city and 37mpg highway. Although many said they could get well into the 40's (about 43mpg seemed obtainable on a long trip).. But even hypermiling there is a law of diminishing returns. Even driving slower speeds you are only going to gain so much in fuel economy...
 
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