Why an Aveo automatic gets poor city MPG

[Thymeclock]

Do you understand that the transmission is not shifting at the points specified by the manufacturer?

It doesn't go into high gear until 45 MPH and there is no way I can make it up-shift any sooner. That affects my fuel economy when I'm mostly driving 35-40.

Even if I wait until 10,000 miles, the correct shift points won't miraculously appear then, will they?

[NorthernAveo]

Do you understand that the transmission is not shifting at the points specified by the manufacturer?

It doesn't go into high gear until 45 MPH and there is no way I can make it up-shift any sooner. That affects my fuel economy when I'm mostly driving 35-40.

Even if I wait until 10,000 miles, the correct shift points won't miraculously appear then, will they?

I would then remove the negative connection from the battery and reset the ECM which will reset the tranny control as well. If that doesn't solve it I would take it to the dealer to have them check on it.

Also, is the Aveo auto a three speed with a lockup torque convertor? If so, they are programmed to go into torque convertor lockup at a certain speed and not before seeing in most cases the manufacturer thinks the engine doesn't have enough horsepower and/or torque to hold the lockup at a lower speed without lugging the engine.

I have a feeling that the 4th gear is the torque convertor lockup and not an actual gear.

Also it won't lockup till the engine is warm.

[Thymeclock]

Also, is the Aveo auto a three speed with a lockup torque convertor? If so, they are programmed to go into torque convertor lockup at a certain speed and not before seeing in most cases the manufacturer thinks the engine doesn't have enough horsepower and/or torque to hold the lockup at a lower speed without lugging the engine.

I have a feeling that the 4th gear is the torque convertor lockup and not an actual gear.

I suggest you re-read my original post and try to comprehend it before responding.

The transaxle is the Aisin 81-40LE. It is the only automatic transmission ever used in all Aveos made since 2004. It IS a four speed transmission. Everything about that specific transaxle is documented, including the specifications for shift points in the Aisin service manual, which is available on-line.

Your conjecture has no basis in fact; as such it amounts to misinformation.

[NorthernAveo]

Also, is the Aveo auto a three speed with a lockup torque convertor? If so, they are programmed to go into torque convertor lockup at a certain speed and not before seeing in most cases the manufacturer thinks the engine doesn't have enough horsepower and/or torque to hold the lockup at a lower speed without lugging the engine.

I have a feeling that the 4th gear is the torque convertor lockup and not an actual gear.

I suggest you re-read my original post and try to comprehend it before responding.

The transaxle is the Aisin 81-40LE. It is the only automatic transmission ever used in all Aveos made since 2004. It IS a four speed transmission. Everything about that specific transaxle is documented, including the specifications for shift points in the Aisin service manual, which is available on-line.

Your conjecture has no basis in fact; as such it amounts to misinformation.

It is strange why you are being so rude when all I was doing was stating the case if it has a lockup torque convertor.

You can see that the first thing I replied with had a question mark right?

Here is what I asked.

Also, is the Aveo auto a three speed with a lockup torque convertor?

Maybe you should read before you act like that when I was trying to help. I was not spreading misinformation at all. The information given was if in deed the tranny was a 3 speed with torque convertor lockup and I never stated that it was for sure it was.

[Thymeclock]

Also, is the Aveo auto a three speed with a lockup torque convertor? If so, they are programmed to go into torque convertor lockup at a certain speed and not before seeing in most cases the manufacturer thinks the engine doesn't have enough horsepower and/or torque to hold the lockup at a lower speed without lugging the engine.

I have a feeling that the 4th gear is the torque convertor lockup and not an actual gear.

I suggest you re-read my original post and try to comprehend it before responding.

The transaxle is the Aisin 81-40LE. It is the only automatic transmission ever used in all Aveos made since 2004. It IS a four speed transmission. Everything about that specific transaxle is documented, including the specifications for shift points in the Aisin service manual, which is available on-line.

Your conjecture has no basis in fact; as such it amounts to misinformation.

It is strange why you are being so rude when all I was doing was stating the case if it has a lockup torque convertor.

You can see that the first thing I replied with had a question mark right?

Here is what I asked.

Also, is the Aveo auto a three speed with a lockup torque convertor?

Maybe you should read before you act like that when I was trying to help. I was not spreading misinformation at all. The information given was if in deed the tranny was a 3 speed with torque convertor lockup and I never stated that it was for sure it was.

If you had understood what I wrote and researched the manual (as I did) you wouldn't have needed to ask or speculate about it. There was no benefit in your offering an hypothetical opinion without first understanding what it actually is, despite your prefacing it as a question.

Fourth gear is fourth gear, and it also has converter lockup.

[Daox]

Thymeclock, can you post up a picture of the shift point graph you are looking at? I think I have the same manual as you but the link you posted isn't working. The manual I have only shows a 1.2, 1.4 and 1.5l engine.

[thebarber]

assumed it was typical that a 4speed slushbox would have a tall 3rd gear relative to 2nd...

lol, and w/ the e-tec i don't think its the tranny thats killing the economy...

[Thymeclock]

Thymeclock, can you post up a picture of the shift point graph you are looking at? I think I have the same manual as you but the link you posted isn't working. The manual I have only shows a 1.2, 1.4 and 1.5l engine.

The link I provided is inaccessible at times, unfortunately (like today, when I checked it).

Here are the links as I copied them:

http://www.anagabriela.ro/.../2.%20AISI ... NSAXLE.pdf

http://www.anagabriela.ro/Manuale%20...0TRANSAXLE.pdf

The same link I provided to EcoModder worked when I uploaded it. The link can also be found by Googling: [Aisin 81-40LE "shift points"]. (Google what is between the [] marks verbatim, and you will recognize it, with it being only one of very few choices.)

Alternatively, I previously printed out the shift points graph that is relevant, scanned it as a JPEG file and tried to post it right now as an attachment, but this site isn't accepting it.

I could use some help on this as I think I'm doing it correctly but I can't successfully upload my attachments.

[ontarian_frog]

http://www.anagabriela.ro/Manuale%20...0TRANSAXLE.pdf

[Daox]

Thanks ontarian_frog. That link worked. That is a different manual than I had too... Gonna have to look it over.

I'll look into your attachment problem too Thymeclock.