2017 1.8 hatch trans fluid change or flush

[Walleyeye]

I’m 1,000 kms away from the 72,000 tranny fluid change interval.

It seems pretty simple to drain, fill to fill plug on side of tranny.

Heres my question. Is a simple drain & fill good or is a flush necessary?

Second question.

I saw this on another post. Is this right?

“There are 2 service schedules in the manual. The "Normal" interval for transmission fluid changes is 156,000km/97,500 mi.

The 72,000km/45,000 mi interval is for "Severe" use (think taxi/commercial or frequent towing).”


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[Gobinator98]

I’m 1,000 kms away from the 72,000 tranny fluid change interval.

It seems pretty simple to drain, fill to fill plug on side of tranny.

Heres my question. Is a simple drain & fill good or is a flush necessary?

Second question.

I saw this on another post. Is this right?

“There are 2 service schedules in the manual. The "Normal" interval for transmission fluid changes is 156,000km/97,500 mi.

The 72,000km/45,000 mi interval is for "Severe" use (think taxi/commercial or frequent towing).”


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Never flush, especially if you suspect there has been wear in the transmission to the point that the fluid has a metallic look to it.


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[Walleyeye]

Never flush, especially if you suspect there has been wear in the transmission to the point that the fluid has a metallic look to it.


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Why never flush?


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[Gobinator98]

Why never flush?


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Re-read my comment. I was referring to having metal in the fluid from excessive wear or just wear in general. If you flush the fluid while it has that metal in it, your transmission will start having problems. The difference between a drain and fill and a flush is that a flush cleans the transmission with a machine hooked up to the cooler lines. A drain and fill just does what it sounds like, a drain and fill.

Ask any reputable mechanic and they’ll tell you the same exact thing. A flush is never a wise idea if you suspect there is excessive wear inside the transmission or if you have been having problems with shifting.


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[JTee2017]

I’m 1,000 kms away from the 72,000 tranny fluid change interval.

It seems pretty simple to drain, fill to fill plug on side of tranny.

Heres my question. Is a simple drain & fill good or is a flush necessary?

First. . from what I see, these little automatics can really use a fluid change interval about every 30K to 40Kmiles even in regular service. The stuff gets black fast.

Drain and fill to level 2 to 3 times is what I and many do. Drain it once and you should get about 4 to 5 quarts out. Measuring what comes out and than filling with same amount is best, but checking at the over flow side port when fluid is up to temp is best. Just drip should start to come out if filled right.

Then drive the car for a few hours or even a week. Repeat the drain and fill again. Many just stop there as +85% or so of the fluid is new.
This is what we have done on the 2014 and a Chevy Cruze in the family. Both still running well at +130K miles.

BTW. . . the reason for just two "drain and fill" cycles is that there is evidence that leaving some used fluid in the transmission is better than all new fluid. . . .. As long as the fluid has not been left and used before it gets burnt or full of metallic particles. The little bit of worn clutch material in the left over fluid apparently aids grip in the fluid so clutches are less prone to have excessive slip. . . or so the idea goes.

 

[Walleyeye]

A lot of great info. Thanks for that!!! I will probably drain and fill twice and be done but have a look at this video and tell me what you think.

The video shows a flush of an equinox but its the same set up on my sonic. Not sure if the top or bottom tranny line is the return though. Seems simple enough to do.

https://youtu.be/1_GaZnwYknw


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