Transmission Fluid Change Question

[ht_addict]

Car (2020)just hit 100k/km. Looking to get Fluid changed out on the transmission. How many times should it be emptied and filled to remove old Fluid. Has anyone removed/replaced the pan to clean out debris stuck to the magnet and give it a good clean.

 

[oddball]

If your goal is 100% fluid change then use a fluid change machine or a shop that uses one. Cheap ones on ebay are usually around $300 (US).

Dropping the pan replaces ~8 quarts-ish out of, I dunno, 13ish? You have to do the math to figure out how many drain/fill cycles to get to the percentage of new fluid you want.

However, a complete change really isn't necessary. A single drain and fill is plenty good for the trans and it'll be happy for another 100km. The only time a full flush is really necessary is if the fluid is burnt or there's been a mechanical failure.

 

[Thomby]

Dropping the pan replaces ~8 quarts-ish out of, I dunno, 13ish?

Are you sure about that? I see 9.7qt / 9.2l in documentation, with other posts claiming ~4qts from the drain plug (and anywhere from another 1.5qt to 3-4qts from dropping the pan).

 

[Ohiocruiser]

Are you sure about that? I see 9.7qt / 9.2l in documentation, with other posts claiming ~4qts from the drain plug (and anywhere from another 1.5qt to 3-4qts from dropping the pan).

It took me under 6 quarts to replace it with transmission pan. Takes about 5 without dropping pan.

 

[Thomby]

It took me under 6 quarts to replace it with transmission pan. Takes about 5 without dropping pan.

If that's the case, an answer to @ht_addict's question is that two changes should leave you ~90% fresh fluid (a little over 8qts new, a little over 1qt old).

 

[rk88]

Check out this video.

Should answer all your questions.

 

[Ah GetFd]

Should never be changed.

All the Kia Stinger Service manuals say Not Required

 

[oddball]

Granted, I was being very lazy and just guessing off of what a particular vendor sells as a package with a new pan/filter.

 

[Ah GetFd]

I state again. I see no reason to change the transmission fluid when the manufacture (who offers warranty), does not recommend any change at all.

Now, if it was required (along with every other maintenance requirement) don't you think KIA would have mandated it throughout the life of the vehicle?

If it is not broken.....don't fix it.

 

[5tinger]

Idea is that a simple drain and refill done periodically will help extend the "optimal" performance over the life of the transmission.

 

[Ah GetFd]

When something is not meant to be messed with......it is more likely that when someone does.....they are going to stuff it up.

They are going to do this incorrectly.....hence people coming in here,.......and asking how to do it........

You know

it's just mindless crap.

oh it should extend the life. .....

How do you know? If it did wouldn't KIA WANT this to be done? Like every other fluid change? Even if it just gave them more maintenance to do to make MONEY. Wouldn't you think they would want you to do this?

And you are from Australia........where I thought you might be a bit smarter at this...

 

[Ah GetFd]

Every manual from Europe to Russia to Australia.............

 

[Thomby]

If we're using warranty coverage as their motivation, that's at most 100k, and for the majority of cars 60k. For many people that's "lifetime", but for others it's not.

A working fluid subject to extreme heat, pressure, and stress in an environment with clutches that wear will suffer degradation, so it's reasonable to wonder where that finite period of reasonable performance ends, and if putting fresh fluid in sooner would protect the aging clutches and bearings.

Every piece of commercial equipment has a transmission service interval, and for enthusiasts on a performance car forum who tune or drive more aggressively than your average "lease for two years and replace it" commuter, I think it makes sense to ask what a hard-use maintenance regimen should be.

 

[LordKOTL]

If we're using warranty coverage as their motivation, that's at most 100k, and for the majority of cars 60k. For many people that's "lifetime", but for others it's not.

A working fluid subject to extreme heat, pressure, and stress in an environment with clutches that wear will suffer degradation, so it's reasonable to wonder where that finite period of reasonable performance ends, and if putting fresh fluid in sooner would protect the aging clutches and bearings.

Every piece of commercial equipment has a transmission service interval, and for enthusiasts on a performance car forum who tune or drive more aggressively than your average "lease for two years and replace it" commuter, I think it makes sense to ask what a hard-use maintenance regimen should be.

US manual for 2022 states to change at 60k miles or 100,000km for severe conditions. Normal conditions (i.e. highway only) says no maintenance.

 

[Ah GetFd]

Yep

That's what it says

Leave it alone

 

[bfglitch]

US manual for 2022 states to change at 60k miles or 100,000km for severe conditions. Normal conditions (i.e. highway only) says no maintenance.

The amusing thing is, when you look in the manual at what counts as "severe conditions" it's pretty much anything a daily driver would come across.

 

[Thomby]

US manual for 2022 states to change at 60k miles or 100,000km for severe conditions. Normal conditions (i.e. highway only) says no maintenance.

The amusing thing is, when you look in the manual at what counts as "severe conditions" it's pretty much anything a daily driver would come across.

I guess part of classifying nearly everything as "severe conditions" is CYA, so when people run their cars into the ground they can say, you should've been on the more conservative maintenance schedule.

If you ever look at those touchscreen Coke Freestyle machines, the Low/No-Calorie section will have 0 calories for small/medium sizes, then 5 or 10 calories for large, which is obviously impossible, and just them falling below some de minimis threshold and rounding to 0.

I feel the same way about a system that requires 60k maintenance in some scenarios, but none forever in others. It would be one thing if MTTF were 500k or 1M miles, but it's almost certainly something like 100k/120k/150k. And even if done without malice, it looks like "anything past warranty coverage rounds to infinity cause it's not our problem".

 

[oddball]

There are also lawn mowers with "lifetime" oil - never change, never inspect! If you define "lifetime" appropriately then it might even make sense. Sadly, I do actually maintain my equipment.

ATF does expire, just like any other lubricant. Fluids and systems have gotten good enough that, yes, the original fill really can last 100k+ without any issues. But it also will help the trans to do a fluid change every once in a great while. I only have 30k miles on mine, but it's been 7 years, so the additive package is almost certainly dead. But it'll certain work *just fine* if I never touch it.

I just changed the trans fluid on my wife's '20 Subaru with 80k miles and a CVT. They don't recommend fluid changes. Guess what? That shit was in bad shape. The fluid is amber color when new - this stuff was almost black.

Doing a fluid change *incorrectly* is far worse than doing nothing, but a fluid change isn't very challenging on these cars. Sure, it's annoying not having a dipstick so everything has to be done from the bottom and using a pump, but it's not the worst setup. The Subaru had me wrapping an arm and a tube around the exhaust pipe to reach the fill port.

In ye-olden-days a fluid "flush" was considered a bad idea, but was still recommended by shops because it was easy and profitable. This usually went wrong either because the trans was already dying ("hey, it shifts weird. Change the fluid and that'll fix it!"... nope!) or the shops used the wrong type of machine that literally forces fluid into the trans which is no bueno.

If someone wants to do it then by all means, go for it! Do read up on fluids and get the correct one. Just like coolants, there are a lot of different ATFs. Sometimes those differences don't matter - and sometimes they really, really do.

 

[LordKOTL]

I guess part of classifying nearly everything as "severe conditions" is CYA, so when people run their cars into the ground they can say, you should've been on the more conservative maintenance schedule.

If you ever look at those touchscreen Coke Freestyle machines, the Low/No-Calorie section will have 0 calories for small/medium sizes, then 5 or 10 calories for large, which is obviously impossible, and just them falling below some de minimis threshold and rounding to 0.

I feel the same way about a system that requires 60k maintenance in some scenarios, but none forever in others. It would be one thing if MTTF were 500k or 1M miles, but it's almost certainly something like 100k/120k/150k. And even if done without malice, it looks like "anything past warranty coverage rounds to infinity cause it's not our problem".

Right on for the bolded. The thing is, the manual actually defines what different severe conditions are; I believe for the trans it's a lot of stop-and-go, or failure to drive it for more than something like 10 miles classifies it as severe. In my opinion, it's a bit underhanded. Yes, most of the time the real 'normal' usage is severe: Short trips, Extensive idling and slow driving speeds, salt-covered roads in winter, heavy traffic, hilly roads, stop-and go. All of those are listed conditions for severe usage. I'd think 90% of the drivers out there, at least in the US, fall under one of those categories, but most never know it because they don't RTFM.

The flipside to that is the average person is stupid. If any auto makers used something like MTBF, any time something broke at less than that value, the Karens (yes, men can be Karens, too) of the world would be haranguing stealerships everywhere that "The MTBF is 150k; the transmission died at 90k". And they drive it in the worst conditions and didn't maintain it.

What it tells me is that you and everyone else is effectively correct--the amount of use and abuse the transmission fluid takes if you only drive in PERFECT conditions will likely last the reasonable life of the vehicle--or at least until the warranty expires. The Severe conditions is not only a CYA for the manufacturer, but also a sort of bait-and-switch making people think that they need less maintenance than they actually do, but then the dealer has an out if they think that they can get away with telling the customer that they should have been maintaining it on the severe schedule.

Personally, I think it's always wise to RTFM, and really read it. My usage falls under severe, ergo the transmission fluid is going to get replaced at 60k. Differentials at 72k. I change my oil at 3k. Ad Nauseum. I'm not one to engage a stealership unless I have to, but I seriously doubt that unless I really screw something up, maintaining under the severe conditions list certainly won't hurt.

 

[D.J.]

Should never be changed.

All the Kia Stinger Service manuals say Not Required

View attachment 92515

In Canada, in basically all driving conditions, which Kia classifies as severe, the schedule says