[nskyline34]

Well feller, my 1999 Buick with 302,000 miles is stiffening from a slipping transmission. The trans that's in it has about 200k on it and still drives just fine but most certainly is slipping. I wanna try ad change the fluid and see if that helps, but I also know that changing that fluid could seal its fate and push it over the edge... What are your thoughts about this? Trans is a 4T65E, V6 supercharged FWD, just my daily driver.

[Irelands child]

Pull that transmission and fix it. New 5 buck +++ a bottle of ATF wont fix a slipping tranny. The clutches and steels are most likely well worn and new fluid wont do a thing to replace the friction surfaces

[nskyline34]

I know it's not going to fix it, I just wanna know if it will slow the wear process. I will pull it and fix it once it finally dies. Just curious if that would help prolong it a little.

[Irelands child]

The wear has happened already - and you can't 'put it back' from a bottle of ATF. Maybe one of those miracles in a can would work for a short time but those are usually no more then a viscosity increaser with a detergent and something to expand the seals - and may cause more harm then good

[nskyline34]

No I realize that. I've heard that all the clutch material in the ATF is actually helping the trans and if you change it, you could be accelerating the wear. That's why I'm asking if this is fact or fiction

[cobalt327]

Originally Posted by nskyline34

No I realize that. I've heard that all the clutch material in the ATF is actually helping the trans and if you change it, you could be accelerating the wear. That's why I'm asking if this is fact or fiction

As said, the wear has already occurred. Changing or not changing the fluid will not add any appreciable life to it. Nor will it take any away.

My advice is take it down for repair NOW not later to minimize the damage.

[DanielC]

I agree with all the advise above, changing the fluid will probably not help. But check the level first.
A few years ago, my Ford Aerostar was slow going from reverse to drive, when it was very cold. The fluid was low, and adding some made the problem go away. The problem also went away when the transmission warmed up a little. My theory, the fluid was slightly low, and when cold, the fluid contracted enough to go below the minimum amount necessary for proper operation. No need to warn me of impending transmission failure, that was at least three years ago, and the transmission is working fine ever since.

[dogwater]

Sounds like you've got your mind made-up already. Hell, go ahead an buy a new filter also, that will help as good as new ATF.It worn out,it's passa.sorta like the dead parriot on Monty Python.

[vinniekq2]

when you take the pan off,see if there is any material in the bottom?

[killerformula]

I would make sure you are full on fluid and that it is the right color. If not then yes, maybe fluid will help. With 300k on it though, its lived its life. I'd put my next dollars into a lower-mileage car. One that runs on regular.

K

[123pugsy]

If the seals are hard and fluid is leaking past and not giving good pressure for clutch apply, something like Lucas may soften them up.

This is the only thing that an additive may possibly help with.

OK, bash away ........

[SSedan64]

Nothing wrong with using the Magic Bottle if you just need it to last a short time until a full rebuild can be done.
You know what that stuff does Puggs, softens & swells the seals. Would be great if it knew when to stop.

[123pugsy]

Originally Posted by SSedan64

Nothing wrong with using the Magic Bottle if you just need it to last a short time until a full rebuild can be done.
You know what that stuff does Puggs, softens & swells the seals. Would be great if it knew when to stop.

I've torn a few down that had Lucas added. The seals were soft and swollen alright.

Maybe using half of what they recommend might help.

[txturbo]

Originally Posted by nskyline34

No I realize that. I've heard that all the clutch material in the ATF is actually helping the trans and if you change it, you could be accelerating the wear. That's why I'm asking if this is fact or fiction

Don't do anything.....if you change the fluid it may never move again.I use to work at a transmission shop and have seen it happen several times. On two of them the trans was working fine until the fluid was changed. One was a 70 Impala.....drove it in....and pushed it out. It wouldn't even back out of the bay.

[1971BB427]

There's no quick fix solution, and if you even spend a couple dollars trying, it will be $2 wasted. Once it starts slipping it's only going to get worse with new fluid, so it's time to toss in the towell.