[XtremeRevolution]

I have been working on an alternate method for changing the ATF on this car for a while, and believe I have most of the creases ironed out. This thread will serve to discuss the procedure being outlined and provide assistance with any steps that still need to be discussed. Note: This does not apply to the Cruze Diesel.

There are two reasons why I am working on this project.

1. The current ATF change method involves performing two drains and re-fills of ATF, which replaces approximately 70% of the old fluid, leaving 30% still in the transmission. It is far from ideal and wastes 25% of the new fluid. The ability to flush out 95-99% of the fluid will provide better results.
2. This is an economy car. It will have a significant following among people who will want to service their own transmissions, and they will need a procedure for flushing transmission fluid that doesn't involve paying their dealer $80-$120 (plus fluid) to do it for them. It also gives them the freedom to choose whichever fluid they wish to.

Before I begin, I need to note that this procedure should not be attempted by anyone who feels it is outside their comfort zone. It is a tad bit more complicated than a simple oil change. AutoGuide.com, CruzeTalk.com, myself, or AMSOIL take absolutely no responsibility or liability from any issues that may arise in your vehicle through following this procedure. The procedure is being posted first for discussion before it is published as a tutorial to iron out any potential issues. The truth is that it is a fairly straightforward procedure, but attention and care must be taken during specific steps. You can't start this procedure and walk out to take care of a crying baby while the car is running. Once you start, you have to finish. Plan accordingly, and proceed at your own risk.

For the purpose of this project, I need community participation in response to items marked in bold red. Since I do not own an automatic transmission Cruze (mine is manual), I'll need help with this. Some of these lines will need to be answered by someone technical enough to perform this procedure on their own.

Fluid required: 12-16 quarts DEX6-spec synthetic ATF. 12 Quarts is an absolute minimum. Using more than 12 quarts produces increasingly diminishing returns, but ensures a more complete fluid change.

Tools Required:

• 11mm and 13mm sockets for removal of drain plug and level plug
• 6+ feet of rubber hose and a c-clamp - refer to writeup to determine size.
• Piece of thick, steel wire, at least 16 gauge. Basically bailing wire.
• Flathead screwdriver
• 4-5 gallon bucket
• Sharpie
• Long neck funnel
• A human capable of following orders
• Clean oil pan
• Bluetooth capable ANDROID Device (phone or tablet) with Torque app installed, OR a scan tool capable of scanning transmission temp OR a ScanGuage that can monitor transmission temp OR a laser infrared thermometer.
• Bluetooth OBD2 adapter
• Torque Wrench
• Sockets/Bits (to be determined below)
• Optional: Replacement transmission line retainers. Anyone have the part number for these?
• Anything else?

Preparation:

1. Take your bucket. Measure out and fill a quart of water. After you've done this, use your sharpie and mark the vertical level on the bucket. Write the quart level on the bucket.
2. Add another quart of water. Repeat step 1. This will have "2 quarts" written next to it. You may nee to stagger the vertical line to the left or the right to make it easier to read.
3. Repeat step two until you have a line that reads 16 quarts.
4. Raise vehicle off the ground level as high as you can get it. Support the vehicle on all 4 corners with 4 jackstands. A lifting jack is NOT a jackstand and is not intended to support a vehicle. Use common sense; do not lift your vehicle on an incline.
5. Connect your OBD2 bluetooth adapter.
6. Start car and allow it to idle for a few minutes to bring the engine and transmission up to lukewarm temperature.
7. Connect your Torque app to the bluetooth OBD2 adapter and verify that the app is reading correctly. If using any other device, connect that instead and skip to step 9.
8. Install the GM PID set in the Torque app (goto settings/ manage special PIDs/ hit menu in that section and touch add predefined set. Should have a GM set there, and create a gauge to monitor transmission temp.)
9. Verify that transmission temp is reporting correctly. Refer to Figure C in the next post. DO NOT PROCEED UNLESS YOU HAVE THE MEANS TO SCAN FOR TRANSMISSION TEMPERATURE. If using the infrared thermometer, simply point it at the metal cooler line fitting.
10. Turn the car off.

Fluid Exchange:

1. Verify that you can remove the fill plug and the level plug. If one is stuck and cannot be at least loosened, find a way to loosen them. Usually, a good whack of a hammer on a center punch dead in the plug will loosen it up, if you have enough space to get the leverage.
2. Place a the oil pan underneath the drain plug for the transmission. Do not confuse this with the engine oil drain plug. Need a picture of this so people don't get confused.
3. Remove drain plug and allow fluid to drain out into the pan using the 13mm socket.
4. Once the fluid stops draining, re-insert drain plug. Tighten to 12 N-m or 106 lb-in.
5. Pour the transmission fluid from the oil pan into the bucket. Using the measurement marks, fill ~0.50-1.0 quart more than that amount back into the transmission. You should have drained approximately 4.25-4.5 quarts.
6. Remove retaining cover from transmission cooler lines. Refer to Figure A in following post.
7. Position oil pan below oil feed return line.
8. Disconnect feed line (the lower one) and allow the transmission oil cooler to drain into the oil pan. - Need to confirm that the lower line is the feed line from the transmission. This is CRITICAL. This can be performed by removing the retaining clip pictured in Figure B using a flathead screwdriver. The retaining clip as it is under tension and may go flying somewhere, so wrap the clip in a cloth rag as it is being removed. A strong magnet may also be a good option.
9. Do any engine shields need to be removed prior to step 8?
10. Allow the transmission oil cooler to drain into the oil pan.
11. Once the cooler has finished draining, empty oil pan into 5-gallon gradiated bucket.
12. Slide rubber hose over end of the feed line and secure with c-clamp.
13. Place the other end of the hose into the bucket and secure to bucket edge or handle using steel wire. You want to make sure that the hose has no chance of sliding out of the bucket. If the rubber hose is firm enough, a hand clamp may work as well.
14. Remove fill plug and place in a safe place.
15. Place long necked funnel into fill port.
16. Have your enlisted human turn the car on while you stand in the engine bay. The bucket should be positioned outside of the car, and you should be able to access the engine bay at this point. Once the car starts, the transmission's internal pump will start pumping out fluid through the hose. That is, assuming you tapped into the correct transmission line. The transmission's pump operates at about 15-30psi, with 15psi being likely at idle. However, the flow rate should be manageable. In other words, it won't drain the entire transmission in a second.
17. The moment the car starts and you have confirmed fluid is being pumped into the bucket, begin filling new fluid into the transmission. Here's the critical part of this procedure. At idle, the transmission will function just fine with one more or less quart than it needs to. Keep track of how quickly you are re-filling the transmission and how quickly the bucket is being filled. Ideally, you will fill the transmission at the same rate as it is emptying itself.
18. If you cannot keep up with the transmission and have fallen one quart behind, have your enlisted human turn the car off. This will stop the transmission from pumping and allow you to catch up. At this point, it is OK to add an extra quart to get ahead of the transmission when you start the car again. Expect to have to shut the car on and off several times.
19. After you've gone through ~8 quarts or so and have ensured that your transmission is NOT more than one quart low (review how many bottles you have filled and how much fluid there is in the bucket) have your enlisted human place their foot firmly on the brake pedal and shift into drive, neutral, reverse, and back into park, and hold each gear for a few seconds. This will get new fluid moving through the valve body.
20. Continue this process until you have 2 quarts left. By this point, the transmission should be pumping much cleaner fluid. Have your enlisted human turn the car off. If you've done this correctly, you will have filled about as many quarts of fluid as the transmission pumped out, give or take up to 1/2 a quart.
21. Re-connect the transmission feed line into the transmission cooler, securing the line with the retaining clip, and reinstalling the retaining clip cover.
22. Position oil pan underneath transmission level plug. The level plug is on the driver's side by the CV shaft. The level plug is located at approximately 4-5 o'clock from the driver CV shaft. Refer to Exhibit D.
23. Instruct enlisted human to start the car.
24. With the engine running and the transmission in PARK, remove the level plug with the vehicle running.This should be an 11mm bolt.
25. Any excess fluid will drain out of the transmission. If nothing drains out of the transmission, add more fluid to the transmission until it does.
26. While scanning transmission temp with your Torque app, allow transmission to rise in temperature until it begins to stabilize. Once transmission temperature has stabilized as high as it can during idle and fluid has stopped draining out of the level hole, re-insert the level plug. Tighten to 12 N-m or 106 lb-in.
27. Remove the funnel and re-install the fill plug. Since this is plastic, just make sure it is hand-tight. Do not over-tighten.
28. Turn car off and lower it off of the jackstands.

 

[XtremeRevolution]

Exhibit A (Retainer Cap):

Exhibit B (Retaining Clip with cap removed):

Exhibit C (Torque App scanning Transmission Temp (3rd from the top left):

Exhibit D (Location of level plug):

 

[carbon02]

I won't be doing this soon, but I have researched it, and I have some information to share.

The Auto Transmission is actually a 6T40 or a 6T40E according to GM Powertrain not a 4T60

I'm not sure how you got the pictures of the lower transmission pipe to radiator. It's really packed in there, maybe theres space from the underside, but I believe the plastic part of the wheel well will have to be removed, and the splash shield that is part of the bottom of the bumper will have to be loosened. If you still have a factory splash shield and it wasn't cut, this probably needs to be removed.

Attached are some pics of files I've obtained from google on the transmission plug locations. They appear to be tapered NPTF plugs. That's probably right, and to my knowledge there isn't a metric equivalent to a tapered pipe tap plug in this size.

The third pic is a location picture of the overflow port.

Some questions for discussion.

Why wouldn't you drain it first, refill and then start flushing out the hose? We'll never know until someone tries this, but I believe it's going to pump faster than it will take fluid from the top. Meaning the "helper" will have to shut off the car every quart to allow the "filler" to catch up.

I've read several posts on this procedure done in the Malibu's, could the level be checked with the wheels on the ground, provided the inner fender wheel well is removed? From my examination this can be done without removing the passenger wheel. Wheels could be on the ground, and the user could remove this plug and allow it to drip.

I need to read the procedure again, but what's the 16 gauge wire for? Pulling back the cover on the transmission line?

New clips for this transmission line are available cheap from Dorman or Rockauto. I wouldn't attempt to reuse it given the difficult location of that connection to see leaks occurring.

 

[BowtieGuy]

You may also want to specify that people performing this should ensure that the fill and level plugs will open before beginning. In the rare occasion one is stuck, better to know before you start than be halfway through this and get a rude awakening.

 

[XtremeRevolution]

I won't be doing this soon, but I have researched it, and I have some information to share.

The Auto Transmission is actually a 6T40 or a 6T40E according to GM Powertrain not a 4T60

I'm not sure how you got the pictures of the lower transmission pipe to radiator. It's really packed in there, maybe theres space from the underside, but I believe the plastic part of the wheel well will have to be removed, and the splash shield that is part of the bottom of the bumper will have to be loosened. If you still have a factory splash shield and it wasn't cut, this probably needs to be removed.

Attached are some pics of files I've obtained from google on the transmission plug locations. They appear to be tapered NPTF plugs. That's probably right, and to my knowledge there isn't a metric equivalent to a tapered pipe tap plug in this size.

The third pic is a location picture of the overflow port.

Some questions for discussion.

Why wouldn't you drain it first, refill and then start flushing out the hose? We'll never know until someone tries this, but I believe it's going to pump faster than it will take fluid from the top. Meaning the "helper" will have to shut off the car every quart to allow the "filler" to catch up.

I've read several posts on this procedure done in the Malibu's, could the level be checked with the wheels on the ground, provided the inner fender wheel well is removed? From my examination this can be done without removing the passenger wheel. Wheels could be on the ground, and the user could remove this plug and allow it to drip.

I need to read the procedure again, but what's the 16 gauge wire for? Pulling back the cover on the transmission line?

New clips for this transmission line are available cheap from Dorman or Rockauto. I wouldn't attempt to reuse it given the difficult location of that connection to see leaks occurring. View attachment 130465 View attachment 130473 View attachment 130481

Typo on the name, I corrected that.

With regard to how to get there, that's what I need someone's help with. Whoever performs this procedure will have to document and take pictures of any additional steps needed. Note that when GM uses a flush machine for this procedure, they also have to remove the lines, so it's not going to be some ridiculously obscure way to do it.

Good idea on draining and re-filling first. That ensures a 100% removal of that amount of old fluid instead of mixing in with new. This is the way I did it on my truck last year. I've updated the steps. Please review and let me know if new steps are needed.

You could check the level with the wheels on the ground, but since you will have to put the engine shields back on anyway, may as well lift it. You won't be able to get to that level plug simply with the wheel turned to one direction, and getting to the fenderwell again just adds another step that takes longer than lifting the car.

16 or larger gauge wire is used for securing the rubber hose to the bucket so it doesn't slip out and make a mess all over your driveway.

I will add a recommendation to purchase replacement clips prior to starting this. As the cars get older, it is likely some of them will be rusted and may break during removal, and the last thing you need is a car that can't move.

You may also want to specify that people performing this should ensure that the fill and level plugs will open before beginning. In the rare occasion one is stuck, better to know before you start than be halfway through this and get a rude awakening.

I'll add a note about that somewhere in there.

 

[XtremeRevolution]

New clips for this transmission line are available cheap from Dorman or Rockauto. I wouldn't attempt to reuse it given the difficult location of that connection to see leaks occurring.

I was unable to find the clips on rockauto. There are some retainers, but they look nothing like what was pictured above.

 

[carbon02]

I was unable to find the clips on rockauto. There are some retainers, but they look nothing like what was pictured above.

It appears that the clips are similar to Dorman 800-801, and can probably be found at a local parts store. GM has used this design with Auto Transmissions for at least 10 years.

Here's a link I found googling.. When looking for Dorman parts it's always best if you can find the sub catalog to bring to the parts store.

http://www.dormanproducts.com/catalog/oesolutions2006/327-342quickdisconnect.pdf

 

[carbon02]

Typo on the name, I corrected that.

With regard to how to get there, that's what I need someone's help with. Whoever performs this procedure will have to document and take pictures of any additional steps needed. Note that when GM uses a flush machine for this procedure, they also have to remove the lines, so it's not going to be some ridiculously obscure way to do it.

You could check the level with the wheels on the ground, but since you will have to put the engine shields back on anyway, may as well lift it. You won't be able to get to that level plug simply with the wheel turned to one direction, and getting to the fenderwell again just adds another step that takes longer than lifting the car.

I've never run a flush machine, but based on the aftermarket parts I've found, I wonder if a flush machine doesn't connect at the transmission by removing the line out of the transmission that goes to the radiator. I need to look, if this is the case the connection would be at the top of the transmission close to the fill point, and much easier to access. However, one would need an old transmission hose to adapt to the transmission, as there's no loose pipe in this example like what is mentioned above in Extreme's post.

Maybe someone that's actually run a flush machine on a Cruze AT can comment where it connects? Probably the best attempt is the radiator connection, like mentioned above, but it's going to be a tight fit under there.

I thought I had a "theory document from Alldata" showing the flow of fluid for the automatic. I'll look for it. It gets a bit confusing, because the Auto transmission fluid goes through both the radiator and the separate dedicated transmission fluid cooler. In which order I'm not sure, and I don't know if it makes any difference.

I guess one connection may allow for a little more flushing of old fluid than the other, but one would assume that the flow would be pressurized upward based on the two connections on the radiator. Upward flow would remove all air in the system.

 

[BradHerr]

I am interested in trying this on my CTD. Another member posted recently about changing their trans fluid and after reading about some advanced replacement fluid I have been itching to replace my fluid. I have about 37k miles on my fluid and want to change it before it gets too old.


-Brad

 

[carbon02]

Here's the drawing I was thinking of.

It looks like the line Extreme is suggesting be disconnected is line #7. I would guess we're dealing with the following flow path.

Out the top of the transmission, in the bottom of the radiator, out the top of the radiator, into the horizontal tranny cooler, out the cooler and return via the side line on the transmission #13.

I guess flow could be reversed. I guess we'll know when someone tries this. Or someone has worked on the 4T60 in some other GM Cars and knows the fluid flow path.

AUTOMATIC TRANSMISSION OIL COOLER PIPES. Fits: 2011 Chevrolet Cruze | Nalley Buick GMC Brunswick

 

[snowvette]

It's going to be tough to achieve those trans temps for a lot of people this time of year. I don't believe mine gets over 160℉ ish during my 100 mile daily commute. I'll check tomorrow.

 

[XtremeRevolution]

It's going to be tough to achieve those trans temps for a lot of people this time of year. I don't believe mine gets over 160℉ ish during my 100 mile daily commute. I'll check tomorrow.

Ziptie a piece of cardboard onto the front grilles of your car and you won't have any problem achieving those temps.

 

[snowvette]

This was after my 50 mile trip to work from Rockford to Barrington. The highest I seen while driving was 156℉. Some sort of air flow restriction will need to be done to trans cooler to get temperature to ideal range i.m.o.

 

[SportBilly]

I have to read this and see how I can help. (Posting to follow)

 

[Diesel Dan]

It appears that the clips are similar to Dorman 800-801, and can probably be found at a local parts store. GM has used this design with Auto Transmissions for at least 10 years.

Do not assume Dorman clips will work because they look the same.
Yes GM started using these decades ago but there are many size variations.

I had a set of dorman cooler lines for my 454 and their own block fittings did not fit. Had to buy ones from the dealer.

 

[XtremeRevolution]

Jon (Sunline Fan) installed grill blocks on his LTZ RS and they improved warm up times significantly. A notable increase in fuel economy will undoubtedly result. It is a great option for anyone who wants to perform this service in the winter.

 

[Justinus]

Pour the transmission fluid from the oil pan into the bucket. Using the measurement marks, fill ~0.50-1.0 quart more than that amount back into the transmission. - Can someone confirm roughly how much comes out?

In three drain and fills that I've done, between 4.25-4.5 quarts have come out each time.

Do any engine shields need to be removed prior to step 2?

The original splash shield will need to be removed to drain the transmission from the drain plug. Cut shields do not block it. I do not know about the redesigned shield.

Once the fluid stops draining, re-insert drain plug. Tighten to 12 N-m or 106 lb-in. - Need socket/bit size.

The drain and level plugs are 11mm. I replaced my drain plug with a magnetic Goldplug which is 13mm.

With the engine running and the transmission in PARK, remove the fill plug with the vehicle running. Can someone confirm which size bit/socket is used to remove fill plug?

Remove the funnel and re-install the fill plug. Can someone verify torque spec?

The fill plug on top of the transmission is a hand loosen/hand tighten cap. There should be no torque spec, it will tighten until it hits a hard stop.

 

[carbon02]

It appears that the fluid flow out of the 6T40 is out the top. Here's some info on the factory flush tool, and a table that shows the flow inlet and outlet hose locations for various GM transmissions.

I couldn't wrap my head around if the flow from the transmission goes to the radiator, and then the tranny cooler or the other way around. I guess it looks like it leaves the top of the transmission, and ties into the lower connection at the radiator.

I'm interested in seeing how bad it is to connect disconnect at that location. Pretty packed looking top down.

Based on AllData Reading, they call the transmission pipe coupler at the radiator a "quick connection" The replacement clip goes into the assembly, and then the feed pipe is pushed in until an audible click is heard.

This may make it easier than thinking that you would have to put the pipe in the coupling and then wrestle with the clip. Clips also appear to be color coated and there are mentions of yellow in the procedure for the clips. (This will have to be confirmed by the first person to do it.)


The Dorman Clips were just a suggestion. It appears there's 3 to 4 different sizes in a bag under that part number. I have posted exploded diagrams above and it looks like the factory clip is <$5.00 from the dealer.


http://www.gmdesolutions.com/equipment/tsb_pdf/transflow_bulletin.PDF

 

[XtremeRevolution]

In three drain and fills that I've done, between 4.25-4.5 quarts have come out each time.



The original splash shield will need to be removed to drain the transmission from the drain plug. Cut shields do not block it. I do not know about the redesigned shield.



The drain and level plugs are 11mm. I replaced my drain plug with a magnetic Goldplug which is 13mm.



The fill plug on top of the transmission is a hand loosen/hand tighten cap. There should be no torque spec, it will tighten until it hits a hard stop.

Thanks for the responses. I will still need to determine if any engine shields need to be removed to drain fluid out of the transmission oil cooler. There should be one on the top and one on the bottom.

It appears that the fluid flow out of the 6T40 is out the top. Here's some info on the factory flush tool, and a table that shows the flow inlet and outlet hose locations for various GM transmissions.

I couldn't wrap my head around if the flow from the transmission goes to the radiator, and then the tranny cooler or the other way around. I guess it looks like it leaves the top of the transmission, and ties into the lower connection at the radiator.

I'm interested in seeing how bad it is to connect disconnect at that location. Pretty packed looking top down.

Based on AllData Reading, they call the transmission pipe coupler at the radiator a "quick connection" The replacement clip goes into the assembly, and then the feed pipe is pushed in until an audible click is heard.

This may make it easier than thinking that you would have to put the pipe in the coupling and then wrestle with the clip. Clips also appear to be color coated and there are mentions of yellow in the procedure for the clips. (This will have to be confirmed by the first person to do it.)


The Dorman Clips were just a suggestion. It appears there's 3 to 4 different sizes in a bag under that part number. I have posted exploded diagrams above and it looks like the factory clip is <$5.00 from the dealer.


http://www.gmdesolutions.com/equipment/tsb_pdf/transflow_bulletin.PDF

If it does in fact leave at the top and plug into the bottom of the radiator, that will make the job simpler as you will only have to remove one fitting to drain the transmission cooler. If you come across the part number for that clip, I can include it.

Looks like we have all of the information we need for someone to get started on this, and to clarify the remaining questions.

 

[HoPo99]

ok, i should be flushing this weekend and am looking to try this process.

my question would be, don't you want to disconnect the line as close to the return back to the transmission as possible... so you let the pump push all the old fluid through the radiator, and through the cooler? if you disconnect before those components, you leave old fluid in them.

and yes, i believe the flow is out of the tranmission, in and out of radiator, in and out of cooler, and back to the transmission. So should the line out of the cooler be disconnected and drained to the bucket?