Changing Tranny Oil? o/ Thoughts

I have heard mixed things on changing Transmission fluid on cars that are high mileage.

People say it does more harm than good.

I have heard from a tech that you either change it often, or leave it alone if its never been done.

What are /o's thoughts on this?

>change it often, or leave it alone
You alone must decide. It is never to late to change course. I myself have chosen the path of maintenance.

I remember something about the gaps and cracks in your gaskets getting plugged by the oil and all the small particulates in it. If you change it those small openings are now open and need to be replugged by the oil and particulates that arent there yet.

Many people fuck it up. I think it's worth a shot. Bad transmission fluid will fuck your shit up just the same.

Manuels and differentials need the oil changed,
but you can fuck up an auto really easy.

>Many people fuck it up
It's a lot harder than an oil change because of the pan and gasket and shit. It's also hard to get the fluid level right because of splashed fluid on the dipstick. Still, by ignoring it an owner demonstrates a lack of understanding of the abstract concept of time and the ability to plan for the future.

Only if your transmission is shit. Good transmissions have drain plugs and fill holes where the oil will spill out when you reach the right amount

>drain plugs and fill holes
But what about changing the filter?

Depends if your transmission needs one or not. Porsche transaxles usually don't

>Porsche transaxles
Glad we got that point clarified.

You will not change anything mechanical by a fluid change. If the clutch packs are worn, they are already fucked, changing the fluid won't do any more harm.

Yours doesn't have the filter built into the pan?

No, ChrisFix has a video explaining it. It's because clutch material is floating around in old fluid and might keep a clutch (yes, autos have clutches buddy) from slipping until you change it. But it can't possibly damage the transmission more to change it. Might make it slip slightly if you really abused your trans but won't cause damage.

>the filter built into the pan
Never heard of that, what car?

most car have like a magnet to get the metal shavings.

Most bmw's, at least since the 2000's

In my experience, automatics usually have filters on the pans.

On a manual, I've never seen anything more than a magnet on the drain plug.

Just reading through this thread, I think some people are talking about autos, some people are talking about manuals.

...

It's almost always beneficial. Not changing it will just keep shit in the transmission wearing it out faster.

Also to add to this, newer fluids have been developed compared to what's currently in your transmission most likely, so switching to a newer synthetic ATF alone will likely make shit better all around.

If you own a car with a slushbox your first immediately decision should be to sell it and buy a standard or a dct.

I change my transmission fluid every 15-20k miles.
I'm told if you don't change it for a long time just don't even bother because it'll start slipping if you do.

first off, oil and fluid refer to two different products. I'm assuming you mean autotragic.
there is never a downside to changing your manual transmissions oil
and it is not possible to flush them

>I have heard mixed things on changing Transmission fluid on cars that are high mileage.
from the guy at the parts store who eats anecdotes and farts conjecture?
>People say it does more harm than good.
they dumb and/or lazy UNLESS they are talking about flushes, see below
>I have heard from a tech that you either change it often, or leave it alone if its never been done.
I've said it before
if it is so neglected that it needs a semi-metallic sludge instead of fresh new oil to function then it's already toast start looking for a new trans or vehicle
>What are /o's thoughts on this?
there's a difference between a flush and a drain
drains are always fine, go do one now,
you will probably have to do several in a row to actually change more than 40-50% of the fluid out

flushes CAN force your neglected trannies metallic sludge into bad places and CAN kill your tranny
however the game of telephone changed this into all flushes are bad, don't change your fluid
and then manufacturers perpetrated this myth with "lifetime fluids"

Helpful post

I wonder...

If only we had something like...

MANUFACTURER RECOMMENDED SERVICE INTERVALS

Follow them, you fucking niggers.

>he doesn't know about lifetime fluids
most modern service intervals are extremely optimistic
and most enthusiasts recommend halving them you mong

If you know the service history of it and that the transmission fluid has been changed regularly then do it. If you don't know the history than it may be more harm than good to change it as it may start slipping once you change the fluid.
Some cars I wouldn't worry about, like Toyota's. They seem to know how to build good auto transmissions.

>if it is so neglected that it needs a semi-metallic sludge instead of fresh new oil to function then it's already toast start looking for a new trans or vehicle
Except that it could be toast 50,000 or 100,000 miles from now instead of just right now.

>don't mind me
>just going to use this abrasive sludge in my trans.
>just because i think it will last 5 more years
I need to go and retrieve my sides

>Engineers spend 10y developing and testing a car to try and make it as bulletproof as possible so the monkeys outside don't wreck it in under at least 2 years of constant sub-human stupidity levels.

>a backstreet Scotty Kilmer "enthusiast" thinks he knows better

If the fluid is lifetime, it doesn't mean the fluid is for 100y wold. It's expected to last the engineering expectancy for that car. Which, if you spent a couple minutes researching, you can quite often find for what kind of mileage a certain model was designed for.

If it isn't lifetime it says 5/10/15/20/ wtv.

Follow the fucking recommended intervals instead of fucking acting as know-it-alls bumblefucks.

"Enthusiasts" 99% of the time are fucking idiots.

The same kind of enthusiasts that recommend 10w40 oil for every kind of engine out there and who have no idea of usage given, ambient temps, world location, fuel conditions and quality.

Dude, just please neck yourself.

And I have seen several people turn a functional car into one that can't be driven just because they changed the fluid. And all I am saying is that you're taking a risk if you don't know the service history.

>turn a functional car into one that can't be driven
I see that constantly at work: putting gas in diesel car (or opposite), driving an overheating car, letting the oil run out, etc. Just because it is possible to fuck up a car doesn't mean avoid maintenance.

Okay, you have to look at it from the mechanics perspective to understand this.

If you've been doing regular maintenance, the chances of your transmission fucking off on the tech after a simple fluid change is incredibly remote.

If the transmission has been severely neglected, the chances of the transmission fucking up after clearing all the shit out becomes rather high. That's on the mechanic if it fails.

HE DOESN'T WANT TO TOUCH YOUR FUCKING PIECE OF SHIT TRANSMISSION BECAUSE HE'S CONVINCED YOU'RE GOING TO BLAME HIM WHEN IT FAILS.

THAT is why they tell you "If it hasn't been done, it's best to leave it alone".

People can still go to Jiffy-Lube and pay for the transmission power-flush.

I've always wondered about this. Got two transmissions from 1965 that call for type F. I'm too afraid to bomb one to find out. I mean it's just hydraulic pressure and lubrication right?

You just need something that's compatible. The compatibility is mostly the viscosity level,, so if you find a newer replacement for Type F fluid it'll be fine.

I have an 04 ranger that I bought in 09 with 185k miles, no idea if the trans fluid was changed before that
But I got it up to 255k miles and the trans slipped pretty bad so I just decided to chance it, either it would be better or it would kill it and I'd get something newer. I changed the fluid and filter in 2015 and it shifted great. After a few 1000 mile trips, some pulling trailers, it started slipping again, noticeably. I changed it again this spring at around 272k miles I think. Started shifting great again, and currently at 275k miles

I say go for changing it, it did wonders for me and has held up great

best post

Most people suddenly decide to change their ATF because the transmission is starting to shit out to fix the problem. Usually the damage is already done at that point and it's a "coincidence" that the ATF change fucked the transmission.

Ding ding ding. It's almost always this.

I just changed my ATF this weekend. 150k mile Nissan. Tranny was not slipping or anything; just figured it was good practice to change the fluid and filter. Everything is working fine, as expected.

>transmissions from 1965 that call for type F
Stay the fuck away from Mercon.

I appreciate the advice. It still runs pretty damn good, too bad it's an fmx and you literally have to order everything for it