Transmission fluid change....is it too late?

[OBIOsim]

2012 Sonic LT hatchback, 1.8 liter, 6 speed auto tranny. Purchased August 2017 with 53,590 miles. Have done twice a year oil changes since....even though I only clock about 4,000 miles a year driving. Replaced stabilizer bar links shortly after buying the car. This summer, replaced front control arms and did full brake job. The car currently has 71,075 miles. This weekend, I will be doing the fall oil change (Mobile 1 full synthetic), installing new plugs, new air filter and new cabin air filter.

Now to the meat of this thread. The Sonic and its dreaded sealed transmission. I have no idea if the fluid is the original fluid or if the dealership I bought the car from changed it before putting it on their lot. I was originally told that the sealed tranny could only be serviced by dealerships. Recently found a video on YouTube showing how to drain the tranny and replace the 5 quarts that are drained. I know that if a tranny is run too long without fluid changes, the fluid gets thin and dirty and the clutch packs begin to wear and when new fluid is put into the tranny, the thinner and clean fluid will result in the worn clutch packs slipping. The new fluid in and of itself does not damage the tranny, it just reveals the damage that has been done by the old, worn out transmission fluid.

If the fluid in my transmission is the original fluid, is it too late to change the fluid?....as in, if I drain out the 5 quarts and replace with 5 quarts of new fluid, is it likely that I will begin having transmission issues? Also, if I do the drain and fill, what transmission fluid type should I use? Would adding a quart of Lucas Transmission additive be a good idea?

The car, including the transmission, is flawless in operation, runs smooth, shifts great, has given me not one bit of trouble...other than previously mentioned replacement issues (stabilizer bar links and control arms and a couple head light bulbs). I have maintained the car well and do not abuse it. I just made the final payment on the car (66 month loan paid off in 50 months) and plan to keep it for at least 4 years and want to do all the maintenance I can to help the car give me reliable use through the coming years.

Thanks for any insights and suggestions!

Tim

 

[JTee2017]

Follow the Sonic and Chevy Cruze 6 speed auto fluid changes. Just make sure you measure what you drain out and fill with exact same amount.
Drain and refill at least TWO time to get +92% new fluid in the system. About +2 quarts remain in the torque converter and radiator transmission oil cooler.
So. . TWO drain and fills are recommended.

Do one drain and fill. . . . drive for a few days or so. . . then do a second drain and fill.

After the 2nd drain and fill. . . . then check the fluid level at the transmission side fluid port fitted with a small bolt . . . with the transmission fluid warm to operating temperature. . . and on a level surface WITH the engine running.
You can do this by first driving the car for 45 to 60 minutes. Jack the car up on driver side, remove the driver side wheel and tire. . .. loosen the side mounted transmission level check port bolt till almost finger loose. . . . but do not remove it.
Let the car down on the jack till level. . then start the engine, let it run for a minute while the trans fluid circulates. . .. then remove the side mounted transmission level check port bolt. Fluid should then just barely drip out with the engine running. If none drips out. . . add some more trans fluid a bit at a time till some does start to drip.
The install the port bolt . . . do not over tighten! Install wheeland tire. . . done.

 

[BigLee]

It's certainly not too late to change the transmission fluid.
I first changed the fluid on my Sonic at 120K, and now 4 drain & refills later, and at almost 146K mliles, the transmission is doing great.

 

[Ksull72487]

It’s kinda an old wives tale. Usually it’s never too late. Depends on how hard the car was driven too. Sometimes old fluid is better than new fluid as things wear out and yes their are cases of bad transmissions running fine on old fluid and then the minute it’s changed problems. It’s rare although.

My rule of thumb is if the car hasn’t been beaten on you can change it at 100k or more. If you were aggressive with it. You either changed it early or maybe don’t want to at all.

Not a mechanic but if a friend has a car with 150k miles and it’s 25 years old. He asks me to change it. First thing I say is how has it been driven. Second thing is be warned it could start slipping. Then again that’s a sign of a bad transmission and old heavier fluid just keeping things working.

Sonics I haven’t seen the issue. And heard of people changing them for the first time well beyond 100k so I wouldn’t be as worried.

The duty schedule is going to play a big part in that. I think the Sonic is 60k maintained and 40k if used commercially or heavy duty.

Side Note: 71k is 100% fine. Your in the green.

Also todays cars and fluids are much better than they wore years ago. That’s why sealed transmissions came around. Never change it last the life of the car. My opinion is change it. I prefer in over maintaining if it’s cheap Theirs usually a drain port. Finding the fill port on a sealed transmission is a bitch. And usually a pain in the ass. (Lots of Fun on BMW, Mini Cooper LMAO) Sonic I’d say still falls in those guidelines. Chevy just choose to recommend a change and provided documentation as well as a well designed drain and fill method.

One last thing to consider is mileage. These Chevy Sonics start to become disposable around 150-200k. So if your pretty far along you may just want to drive it to the ground lol.

Also JTEE offered good advice. It’s not a bad idea to do it twice. You’ll never get it all out in one go but that’s up to you. At 71k I would definitely do it. I consider that 100% in the green.

Spark plugs I would do every 30k - 40k. Like $20 bucks on these 4 cylinders and takes seconds. 60k is about right for a turbo and 100k for naturally aspirated. Turbos definitely wear Iridium’s out much faster. And it’s worth getting a look at the gap before 60k. My rule of thumb has been half it. If they call for 100k on spark plugs. Go with 50-60k. If they call for 60k then 30-40k. Turbos always come in at 60k lol. Oil I was different with on just about every car. Personally I go for Penzoil Platnium always the manufacturer spec like Dexos or BMW Long Life. Penzoils natural gas stuff has impressed me. I’ll wait till the idiot percentage gauge gets down their. Sometimes I reset it at 80-90% life left as the oil I know will go a lot longer. But 7,500 miles is my rule of thumb maybe 10k. 15k is a no go and 5k-3k your waisting money. Oils come a long way. Mini was telling people 15k at one point. But they reduced it to 10k. Penzoil Platnium really holds up long term. So that’s your call. But that’s my experience. I used to be a really big fan of the 3k synthetic oil change. Todays synthetic oils and Project Farm on YouTube as well as me sending stuff to black stone labs. Unless your racing the car it’s stupidity to change it that early.

And no to any additives. Don’t add anything. The only additives I might use is fuel injector cleaners or substituting a a quart of oil for a quart of transmission fluid in the crank case to clean up a engine depends on the car again. Heet I’ve used also to help an old car pass emissions or on cars that are stored. Most the additives are complete BS. Use good gas lol. Techron from Walmart isn’t bad for a fuel injector cleaner. $4 tops. Lucas is a big waste of money. I remember when that stuff got big at autozone way back in the day. Lol. If your trans is totally screwed and you can’t afford a repair or new car. Then we can talk about the snake oils since their are unreliable ways to fix things or get you running. Lol.

Last and final thing when those plastic arms break. Buy metal ones. Their are good suppliers out there that sell them. Good gas goes along way. I was running 93 for awhile with good gains in MPG and performance. Then I decided it’s not worth it in this little car. Running a round or two of 93 octane isn’t a bad idea. Then switch back to 87 and rely on the knock sensors for the savings if your un tuned. Top Tier gasoline only. Stay away from that speedway ****. I won’t even gas my company semi up at speedway and that’s diesel.

Somebody provide me a bunch of thumbs ups for this. Lol

Now for the Joke: Have you ever seen a semi run on 17 gallons of 93 octane and about 20 of diesel. LMAO. BP Gas station. I figured the green handle was the diesel. Not at BP since that’s their company color. 78 stops that day. I smoked out the neighborhoods and watched my exhaust stack blow huge clouds. 2014 international. She’s still running. You can’t put diesel in a gas engine. But some of us actually do fill up with 50-100 gallons of diesel and add a a gallon or two of gas it thins out the mix as diesel likes to gel up fast in winter.

I did that on almost 50/50.

Company ridiculed me for not calling it in and having a mechanic come out to drain the tank. I’m like that would of taken hours and stops likely rescheduled. I know a diesel will eat just about anything. So I said the job got done didn’t it. Every customer served. Lol okay drain the tank.

You want that car to last as you don’t want a payment. Just start learning what you can about it. And try to get routine maintenance done earlier than later. Otherwise just drive it.

 

[Kingblitz]

2012 Sonic LT hatchback, 1.8 liter, 6 speed auto tranny. Purchased August 2017 with 53,590 miles. Have done twice a year oil changes since....even though I only clock about 4,000 miles a year driving. Replaced stabilizer bar links shortly after buying the car. This summer, replaced front control arms and did full brake job. The car currently has 71,075 miles. This weekend, I will be doing the fall oil change (Mobile 1 full synthetic), installing new plugs, new air filter and new cabin air filter.

Now to the meat of this thread. The Sonic and its dreaded sealed transmission. I have no idea if the fluid is the original fluid or if the dealership I bought the car from changed it before putting it on their lot. I was originally told that the sealed tranny could only be serviced by dealerships. Recently found a video on YouTube showing how to drain the tranny and replace the 5 quarts that are drained. I know that if a tranny is run too long without fluid changes, the fluid gets thin and dirty and the clutch packs begin to wear and when new fluid is put into the tranny, the thinner and clean fluid will result in the worn clutch packs slipping. The new fluid in and of itself does not damage the tranny, it just reveals the damage that has been done by the old, worn out transmission fluid.

If the fluid in my transmission is the original fluid, is it too late to change the fluid?....as in, if I drain out the 5 quarts and replace with 5 quarts of new fluid, is it likely that I will begin having transmission issues? Also, if I do the drain and fill, what transmission fluid type should I use? Would adding a quart of Lucas Transmission additive be a good idea?

The car, including the transmission, is flawless in operation, runs smooth, shifts great, has given me not one bit of trouble...other than previously mentioned replacement issues (stabilizer bar links and control arms and a couple head light bulbs). I have maintained the car well and do not abuse it. I just made the final payment on the car (66 month loan paid off in 50 months) and plan to keep it for at least 4 years and want to do all the maintenance I can to help the car give me reliable use through the coming years.

Thanks for any insights and suggestions!

Tim

Hey Tim I also have the same wounder as you.i bought mine with 28k it's a 2014 LT and it has now just 102.just did the timing belt and transmission coolant lines and mechanic said fluid is dirty and should be changed .but I'm also worried like u are if things will go wrong if I change the transmission fluid.cause I don't want it to slip..I'll do some research and keep u updated on what I find

 

[To_the_levee]

Did you end up changing the trans fluid? If so, any slippage?

 

[SuperS13]

Got a 2013 Modified sonic 1.8L . I do oil changes every 4-6k miles. And the pennzoil platinum natural gas oil is mint. I do plugs every 20k, the trans fluid changes I do every 18k. It's best to drain and fill twice but in between do 500 mile cycle. Usually a drain and refill on a 6spd auto is around 4.8 quarts-5.4 quarts. I believe its 7 quarts all together. CV axles start going around 78-80k miles depending on you drive. Follow my youtube channel @Sonic86 for more

 

[mjp2d1]

2012 Sonic LT hatchback, 1.8 liter, 6 speed auto tranny. Purchased August 2017 with 53,590 miles. Have done twice a year oil changes since....even though I only clock about 4,000 miles a year driving. Replaced stabilizer bar links shortly after buying the car. This summer, replaced front control arms and did full brake job. The car currently has 71,075 miles. This weekend, I will be doing the fall oil change (Mobile 1 full synthetic), installing new plugs, new air filter and new cabin air filter.

Now to the meat of this thread. The Sonic and its dreaded sealed transmission. I have no idea if the fluid is the original fluid or if the dealership I bought the car from changed it before putting it on their lot. I was originally told that the sealed tranny could only be serviced by dealerships. Recently found a video on YouTube showing how to drain the tranny and replace the 5 quarts that are drained. I know that if a tranny is run too long without fluid changes, the fluid gets thin and dirty and the clutch packs begin to wear and when new fluid is put into the tranny, the thinner and clean fluid will result in the worn clutch packs slipping. The new fluid in and of itself does not damage the tranny, it just reveals the damage that has been done by the old, worn out transmission fluid.

If the fluid in my transmission is the original fluid, is it too late to change the fluid?....as in, if I drain out the 5 quarts and replace with 5 quarts of new fluid, is it likely that I will begin having transmission issues? Also, if I do the drain and fill, what transmission fluid type should I use? Would adding a quart of Lucas Transmission additive be a good idea?

The car, including the transmission, is flawless in operation, runs smooth, shifts great, has given me not one bit of trouble...other than previously mentioned replacement issues (stabilizer bar links and control arms and a couple head light bulbs). I have maintained the car well and do not abuse it. I just made the final payment on the car (66 month loan paid off in 50 months) and plan to keep it for at least 4 years and want to do all the maintenance I can to help the car give me reliable use through the coming years.

Thanks for any insights and suggestions!

Tim

is it possible to change just the filter? I would suggest capturing the old fluid, changing the filter and putting the old fluid back into the tranny… You are correct if the fluid has never been changed, new transmission fluid, will destroy it, but a new filter would do the tranny lots of good transmission fluid ask more of like a detergent and not a lubricant.