Chevrolet Cruze Forums banner
1 - 20 of 31 Posts

·
Premium Member
Joined
·
661 Posts
Discussion Starter · #1 ·
i apologize if this a repeated thread, but the ones i found had more to do with bad shifts or lurching

So as the title says, this a very specific problem that is causing me some concern now. I go to school in a cold area... and live on a hill that is a 9% grade, every morning since the temperature got cold i have noticed the car allows the rpm to stay very high without shifting gears. Even in manual mode the computer will not let the car completely engage. This has caused a delay in acceleration and the car seems to get confused

as an example. doing 35 mph i am in 5th gear at 2700 rmp. It will not allow it to go into 6th and dropping the gear does nothing to the rpms. I have more of an issue when climbing because there is greater strain on the car, but it even does it going down hill. My father tells me that GM has built this into the cold start for the cars so nothing gets damaged.

once the car gets warm, past say 135 it will drop into proper gear and i when i say drop i mean it. i saw my rpm's go from 2200 to 1200 as if there was a normal shift..

is this something that other people have noticed?
 

·
Registered
Joined
·
1,166 Posts
first what year is the car? Also note there has been a number of updates to the programing in cruze vehicles.
 

·
Registered
Joined
·
58 Posts
I have a 2012 LTZ and when you first start the engine the RPM's run around 1500. If you take off from that point the RPM's will run about 700 higher then normal until the temperature has reached around 150F. The colder the temperature the longer obvisouly it will run at a higher RPM. This sounds like it may be annoying since your going up a steep grade. This sounds normal to me though.
 

·
Premium Member
Joined
·
6,918 Posts
Where is the mention of the transmission slipping? title seems a bit exaggerated. The trans is behaving normally, it will hold gears a bit longer while cold.

Also if you are driving on a steep grade 5th gear would be much more appropriate & put less strain on the engine(warmed up or not), RPM of an engine is not a analog of engine load. 6th gear + hill grade + low RPM = greater load. Engine doesn't make any power below 2,000RPM, with that kind of grade best bet is to downshift to 5th, bring up the RPMs & not stress anything.

Sure you cold drive faster & get the RPMs in 6th above 2,000RPM, but the difference in gear ratios between 5th & 6th & torque multiplication one would see 5th puts much more power down for any given RPM.
 

·
Premium Member
Joined
·
661 Posts
Discussion Starter · #5 ·
2012 cruze

i ahve heard about the problems with the transmission before but my car doesnt have nay of those issues

Where is the mention of the transmission slipping? title seems a bit exaggerated. The trans is behaving normally, it will hold gears a bit longer while cold.
The slipping is happen in 2nd and up, the car keeps the rpm's up no matter what i do to try and bring them down.
Also if you are driving on a steep grade 5th gear would be much more appropriate & put less strain on the engine(warmed up or not), RPM of an engine is not a analog of engine load. 6th gear + hill grade + low RPM = greater load. Engine doesn't make any power below 2,000RPM, with that kind of grade best bet is to downshift to 5th, bring up the RPMs & not stress anything.
i can understand that it ahs the best torque output but the fact is my car normally is at 1200 rpm doing 40mph in 5th gear( i will double check that if i get a hcance i may be a bit off)... when it is cold its doing about 2800 rpm at 33mph.
Sure you cold drive faster & get the RPMs in 6th above 2,000RPM, but the difference in gear ratios between 5th & 6th & torque multiplication one would see 5th puts much more power down for any given RPM.
i rather not drive faster i do not care what gear i climb in, i have started to notice that the car will shift up and then back down( when its fully automatic). i could be wrong about all this and overly conceren but i just was curious to see if this normal.

once it is warm it runs perfect and responds when i want it to, i was just curous ( like the open lood cycle) does the car have a built in setting so when the transmission oil is cold and thick it allows some slipping to protect the parts.
 

·
Premium Member
Joined
·
661 Posts
Discussion Starter · #6 ·
@spacedout:

i thank you for your help, i do appreciate and respect what you are saying and understand what you are saying.
 

·
Premium Member
Joined
·
6,918 Posts
I don't know if the cruze has a lockup torque converter(I would assume so since most automatics with a torque converter do), but on my 2004 cavalier the automatic would not lock up the converter when the car was cold, at highway speeds with the torque converter not locked up the car would be running 500-600RPM higher than normal. Once the car warmed fully it would lockup & RPM would drop to normal.

I would suspect the cruze is the same & thought I noticed a bit higher RPM in 5th & 6th the other day when the car was still warming. I know on my 2012 automatic is like 58MPH is 2,000RPM in 6th. I would check & see if it was higher when cold but right now its only 50 degrees so It will have to wait till the weather swings colder again.
 

·
Premium Member
Joined
·
661 Posts
Discussion Starter · #8 ·
i did a quick check the other day and my car is at 2000 rpm in 5th at 40mph and when it was cold it was at 2500 or 2700 at 35-37mph
 

·
Registered
Joined
·
58 Posts
I noticed something similar in my '12 LT auto. When the car is cold, it adds the extra ~500 rpm to warm up (my guess). Once I freaked out b\c when I took off from a parking lot onto a small highway (0-90 km/h) in manual mode (it was about 0 to -5 Celsius), I noticed i was going around 70km/h and my 5th gear rpm was near 2.7k and when I shifted to 6th @ 80km/h it was about 2.5k. At first I thought something was wrong, but once the car got warm it straightened out. Not saying that it's A-OK b\c Cruze is a piece of s**t car tbh, but it sounds somewhat logical.
 

·
Premium Member
Joined
·
2,020 Posts
I don't think you're experiencing slippage. Slippage would be more along the lines of the car revving up then the car would jerk or slam into gear (clutches finally catching after enough pressure builds up), or the car would jerk going down the road.

1) I highly recommend you let the car warm up. It takes about 30 - 60 seconds. Is that really going to make you late? No, it isn't so don't treat the car like crap.
2) I wouldn't attempt to climb a hill in an overdrive gear. It puts additional stress on the transmission. Put it into a 1:1 gear which should be 4th (i'm assuming the A/T's have two OD gears). Your car will try to go into the gear that it thinks is most appropriate which isn't always the right thing to do and that's why it flops back and forth a lot because 6th doesn't keep the car where it needs to be. Just drop it into an appropriate gear and let it stay there until your climb is done.

A word about A/T fluid. The A/T fluid goes through a heat exchanger that's normally mounted on the radiator. This is NOT, N-O-T a cooling system. It is a temperature control system. A/T fluid has a specific operating temperature range and the purpose of the system is to bring it up to that temperature and keep it there. If you're just getting in and taking off from a dead cold start, what do you expect? Many things could happen, the fluid is too cold and thick to get through the valves which would cause low pressures and thus, slippage.

Having said that, I have no idea how the A/T's work in the newer cars. My knowledge comes from dealing with performance chevy 700R4/4L60E 2004R/4L80E trannies but most of what I know remains the same.
 

·
Premium Member
Joined
·
661 Posts
Discussion Starter · #11 · (Edited)
1) I highly recommend you let the car warm up. It takes about 30 - 60 seconds. Is that really going to make you late? No, it isn't so don't treat the car like crap.
i would appreciate it if you did not judge the way i operate my vehicle, i baby my car. every chance i get i open the hood, check fluids add fluids and make sure this car is in good order... the whole reason for this thread was to make sure that y car was acting normally.

and for your information i do let the car warm up, for a lot longer then 30-60 seconds. normally i wait until the car gets above 90 degrees which can take a minute..

2nd, i do not chose the gear that it is in, i let it do that itself i only intervene when i know i will need a bit more power and i drop down a gear.

lastly if you have no idea how a A/T works and you do not drive one then how can u comment on this thread saying that i am doing something wrong. i can drive both a M/T and A/T so i understand how both work.

i would ask you again to hold your personal opinion about how i treat my car, you could have asked and i would have told you that i do let the car warm up. that would make you entire " no , so don' treat your car like crap." comment just a ignorant comment based on incomplete information .


unless your comment was not direct at me in which case... my bad
 

·
Premium Member
Joined
·
2,020 Posts
@kfr291 I will apologize for my judgmental tone (spent a lot of time dealing with...customers), but I stick with what I wrote.

once it is warm it runs perfect and responds when i want it to, i was just curous ( like the open lood cycle) does the car have a built in setting so when the transmission oil is cold and thick it allows some slipping to protect the parts.


Exactly what I said about ATF operating temperatures. A/T's use fluid to control pressures. When the fluid is cold it's too think to move through the veins of the valve body which causes low pressures and makes the pump work harder. If the pressure isn't where it needs to be then it's possible the computer is making it act out of the ordinary.

35mph seems too slow for 5th gear, especially if you're on a grade. moving the selector up a gear won't force it to move up. The valve body/computer will control when it upshifts. Only in TRULY manual valve bodies can you move the selector into a lower gear and force it to shift down. "Manual" mode is still automatic mode. It won't let you downshift from 5th to 1st if you're already doing 80mph at 4k rpm. Sure, you can move the selector (Assuming no lock out bars are used) but the tranny will ignore you until it's safe to do what you want.

every morning since the temperature got cold i have noticed the car allows the rpm to stay very high without shifting gears.


I'm assuming because the ATF temps aren't where they need to be so the torque converter is staying unlocked (to help heat up the fluid). The car will raise from 200-800 RPM when the converter is unlocked.

You may also notice the car acting as if it's slipping when the RPM's raise a few hundred then drop again over and over. This is the converter locking and unlocking. Usually when you increase the throttle enough, the converter will unlock to 1) increase RPM's to help acceleration 2) prepare for a downshift.

lastly if you have no idea how a A/T works and you do not drive one then how can u comment on this thread saying that i am doing something wrong


I have 4 years of experience working in a well known performance transmission shop where stock chevy trannies were rebuilt for performance and retrofit into custom hot rods, street cars and bracket racers. I've written and photographed build articles that were published in magazines such as Super Chevy, Vette Magazine and I've ran booths at most of the popular car shows in SoCal as well as the SEMA show. I know plenty.

Let me rephrase my statement though, I don't know some of the specifics of how the newer trannies have changed. I have not kept up. Much more electronics than before so I don't know how it changes the behavior of the trannies, but the principals remain the same.

As far as you doing something wrong, I only said you weren't letting it warm up enough and thats why you're seeing the issues. The gear selection is your choice, but the car doesn't always know what's best.

Now, if you think it's slipping then check the ATF. Is it gritty? This will indicate clutch material is in the oil (slippage). Does it smell burned or is it super dark/black? Another sign of slipping. I don't know about Synthetic ATF but non-synthetic ATF usually smells kind of sweet. Oil analysis is perfect way to determine if you're slipping over time.
 

·
Premium Member
Joined
·
661 Posts
Discussion Starter · #13 ·
@kfr291 I will apologize for my judgmental tone (spent a lot of time dealing with...customers), but I stick with what I wrote.

[/COLOR]

Exactly what I said about ATF operating temperatures. A/T's use fluid to control pressures. When the fluid is cold it's too think to move through the veins of the valve body which causes low pressures and makes the pump work harder. If the pressure isn't where it needs to be then it's possible the computer is making it act out of the ordinary.

35mph seems too slow for 5th gear, especially if you're on a grade. moving the selector up a gear won't force it to move up. The valve body/computer will control when it upshifts. Only in TRULY manual valve bodies can you move the selector into a lower gear and force it to shift down. "Manual" mode is still automatic mode. It won't let you downshift from 5th to 1st if you're already doing 80mph at 4k rpm. Sure, you can move the selector (Assuming no lock out bars are used) but the tranny will ignore you until it's safe to do what you want.



I'm assuming because the ATF temps aren't where they need to be so the torque converter is staying unlocked (to help heat up the fluid). The car will raise from 200-800 RPM when the converter is unlocked.

You may also notice the car acting as if it's slipping when the RPM's raise a few hundred then drop again over and over. This is the converter locking and unlocking. Usually when you increase the throttle enough, the converter will unlock to 1) increase RPM's to help acceleration 2) prepare for a downshift.



I have 4 years of experience working in a well known performance transmission shop where stock chevy trannies were rebuilt for performance and retrofit into custom hot rods, street cars and bracket racers. I've written and photographed build articles that were published in magazines such as Super Chevy, Vette Magazine and I've ran booths at most of the popular car shows in SoCal as well as the SEMA show. I know plenty.

Let me rephrase my statement though, I don't know some of the specifics of how the newer trannies have changed. I have not kept up. Much more electronics than before so I don't know how it changes the behavior of the trannies, but the principals remain the same.

As far as you doing something wrong, I only said you weren't letting it warm up enough and thats why you're seeing the issues. The gear selection is your choice, but the car doesn't always know what's best.

Now, if you think it's slipping then check the ATF. Is it gritty? This will indicate clutch material is in the oil (slippage). Does it smell burned or is it super dark/black? Another sign of slipping. I don't know about Synthetic ATF but non-synthetic ATF usually smells kind of sweet. Oil analysis is perfect way to determine if you're slipping over time.

sorry as well i may have jump a bit more then i should have, been one of those days, i havnt noticed any burnring smells or any grit anywhere. since i have noticed the issue i have taken pre cautions to help the car, taking a different route that doesnt make me drive 45 mph before the car is at temp. like i siad earlier allowing the car a bit more time to warm up, i even allow the car to sit idle in gear ( with my foot on the brake ) for a 20 seconds or so to get things moving. once it warms up i notice no problems, but warm means 135 degrees,( coolant temp) the thing i am taking about seems consitant enough that it seems to be programed into the car, there is no lurching or surges in power, outside of higher rmp the car runs normal
 

·
Premium Member
Joined
·
2,020 Posts
Just had a thought. When I went in and complained about my Kia's A/T, they came back and said all of the servo's and valves reported to be working correctly. I guess they were able to check them through the OBD2. It might be worth checking for codes or if you have a tune, asking Vince if there is a way to log information from the tranny.
 

·
Premium Member
Joined
·
1,283 Posts


I'm assuming because the ATF temps aren't where they need to be so the torque converter is staying unlocked (to help heat up the fluid). The car will raise from 200-800 RPM when the converter is unlocked.

Sounds like the "problem" is just running with an unlocked converter while cold. That's normal in many vehicles.
 

·
Premium Member
Joined
·
2,704 Posts
1) I highly recommend you let the car warm up. It takes about 30 - 60 seconds. Is that really going to make you late? No, it isn't so don't treat the car like crap. 2) I wouldn't attempt to climb a hill in an overdrive gear. It puts additional stress on the transmission. Put it into a 1:1 gear which should be 4th (i'm assuming the A/T's have two OD gears).
Your car will try to go into the gear that it thinks is most appropriate which isn't always the right thing to do and that's why it flops back and forth a lot because 6th doesn't keep the car where it needs to be. Just drop it into an appropriate gear and let it stay there until your climb is done.
Um, no offense but you are commenting on something you have no knowledge on. You drive a manual transmission in a warm climate. 1:1 is actually 5th in Automatic Transmission. It takes WAYYYYYYYY longer than 30 seconds for these cars to warm up in our New York winter climate.

To the OP, this behavior is 100% normal. It is built into the ECU to hold the revs higher until the engine warms up to build the heat. It is nothing to be concerned about. My car behaves the exact same way. My advice is to let it idle until about ~1000 RPMs of idling RPMs (takes no more than 2 minutes) then be easy on it until it warms up a bit. You don't have to let it idle too long though.
 

·
Premium Member
Joined
·
2,020 Posts
Um, no offense but you are commenting on something you have no knowledge on.
See my previous post. No offense taken.

You drive a manual transmission in a warm climate. 1:1 is actually 5th in Automatic Transmission.
Interesting. Wonder why the A/T has a single OD while the M/T do not.

It takes WAYYYYYYYY longer than 30 seconds for these cars to warm up in our New York winter climate.
I said the cold start cycle takes about 30-60 seconds. Never said the car will warm up that fast.
 

·
Premium Member
Joined
·
2,704 Posts
Interesting. Wonder why the A/T has a single OD while the M/T do not.
I think it has to do with the weight maybe? GM has the same gears and / or gear set-up in the Cruze and Verano and other similar platform cars. The only thing they really change final drive.

The gears for automatic 6 speed transmissions are like this:

1-3: Acceleration, 1 being extremely deep. It is not "needed" as you can accelerate in manual mode from 2
4: Passing gear. No matter what, whenever you give it some juice ~40+ mph, it always wants to shift into this gear. This is a 1.445:1 on the Cruze
5: Standard 1:1 drive
6: Overdrive

Manual transmissions don't really need a "passing gear" because you have free control over the box.
 

·
Premium Member
Joined
·
661 Posts
Discussion Starter · #19 ·
To the OP, this behavior is 100% normal. It is built into the ECU to hold the revs higher until the engine warms up to build the heat. It is nothing to be concerned about. My car behaves the exact same way. My advice is to let it idle until about ~1000 RPMs of idling RPMs (takes no more than 2 minutes) then be easy on it until it warms up a bit. You don't have to let it idle too long though.
i do let the car warm, it gets to about 900 rmp and coolant at 100 degrees before i leave. its while driving and in gear that the rpms are about 500-600 higher then normal... again i figured it was built into the ECU, i want to run it past other Cruzers to see if it was true ( just in case it was not normal )

i thank you all for your help.
 

·
Premium Member
Joined
·
2,020 Posts
I'd be interested to get a temp gauge on the trans. Is there a port to hook one up, or can it be had through logging? I'd be very interested to know at what temps the ECU starts to lock the converter and how long it takes for your ATF to get up to operating temp.
 
1 - 20 of 31 Posts
Top