Ye olde death to the AT when flushing with fresh ATF

[Pablo]

This thing comes up, is beat down and goes around and around. Does flushing a moderately to well used tranny cause death. This popped up in a Volvo forum:

"Actually, that "rumor" is FACT. If you go more than about 75,000 miles on ATF in an automatic, or it starts to get burned, changing the ATF will do more HARM than good.

Why? It's not varnish, it's ash and calsium both of which are added to ATF for various reasons. This stuff, particularly calsium, is suspended in the ATF until it gets too hot or worn out, then it begins to migrate into the clutch facings. When you change out the old, and bring in the new, you add a new batch of calsium to the system, and there is no where for it to go, as the clutches are already full of it. So instead of gripping, they slip torching the trans.

Lesson: Change your ATF (drain the pan) every other year or 25,000 miles, it's cheap insurance.

Source: Former Ford powertrain engineer."

Other than his badd schpelling, is this guy fullosheet?

 

[got boost?]

there are too many variables to make a blanket statement like that. I've flushed a tranny with 220k + miles that worked fine afterward. many gm trannies are recommended for a 100k miles interval, and from what I've seen that IS okay. ford trannies are generally not as tough as gm trannies, but I've done a flush on a 140k mile AODE that has lasted. btw I know the full service history for both cars. if a tranny has miles on it and is slipping, THEN flushing the ATF will cause more problems.

 

[jsharp]

My guess is he's full of it.

I'm guessing in about every case that new fluid "caused" this problem, it went something like this.

1. Guy has a slipping tranny, checks oil, notices it's low and/or burnt. He's *never* changed it and probably hasn't even had the dipstick out before.

2. He asks around for "advice" on how to fix it for under $25, meanwhile he keeps driving it and it's getting worse.

3. After being told the trans is probably toast and there's no way to save it for such a little amount of money, one person advices him to try changing the oil and filter though he says he's sure it won't help.

4. He prices parts and fluid, sees it's going to cost more like $50 and decides to think about it some more. Yes, he's still driving it and it's still getting worse.

5. He sees the "Jiffy Lube Trans Service Special - $19.95" in the Sunday paper. He waits until the day before the sale ends and heads down for the "service." Of course he's still driving the car. And towing heavy things.

6. He has the service done and notices the trans is still slipping. Amazing...

7. He asks around again, only now the question he asks is - "What would make my trans slip after getting the oil and filter changed?"

8. 18 people pipe up and say theirs did the same exact thing, but they forget just like he did that it was on it's last legs day/months/years before the $19.95 "Trans Service."

9. Yes, he keeps driving. And towing heavy things. In hot weather. With the fluid low. "I shouldn't need to check it! I just got it changed!"

10. Yep, it fails.

11. He's telling his friends about it over a few (six packs) of beer and a new myth is born.It appears on the internet within 24 hours. "Changing the fluid in my auto trans made it slip, then fail. And now it's not 18 people, it's 18,000...

12. We talk about it here...

Seriously, I'd like to understand how this works if it's real. I just can't see it...

 

[got boost?]

something else I have to point out is that I know several engineers (I'm mechanical) who only work on a VERY specific part of the design/testing/etc process and have no real motivation/desire to learn everything about whatever it is that they're working on. So, even if the guy who originally posted that did work for ford powertrain, it doesn't necessarily mean he knows anymore about trannies than anyone else.

 

[unDummy]

Same old story.
Tranny slips.
Hit quickeeloob for flush. Blow tranny.
Hire lawyer to sue quickeeloob for new tranny.
New tranny at the cost of a flush and letter from lawyer.

This happens over and over. Quality shops will actually take the car for a ride to make sure that it is functioning properly prior to service. If they don't drive it, then they are not a "quality shop" with a reputation to worry about.

I've flushed hundreds of trannies without losing any regardless of mileage. I've rebuilt enough to know that heat & OEM cost cutting are the two things that kill ALL transmissions.

 

[JohnBrowning]

Myth, I have personel changed fluid on more then one abused trans. It has never caused me any problems. I think the key was that the transmissions were still proberly function.

 

[cousincletus]

Know someone that had this happen (1997 Jeep Grand Cherokee) with about 75,000 miles. Lucky for her she had the extended warranty. Tranny was doing OK until just after the flush at the lube shop. Best advice Ican give is to service every 25,000 miles. If you have a neglected tranny, don't flush it.

 

[metroplex]

change it every 15k miles.

 

[JohnBrowning]

Yes, Preventive maintence is the way to go. I have never used a proffesional grade solvent evacuation before. I used Auto-Rx in a trans with 109,000 miles and OEM fluids in it. I came by the vechiles used. I know it was OEM fluid because the bolts had no marks on them at all and the filter was the factory istalled filter, the amount of deposits on the magnet were insane and the fluid was almost the color of slightly used motor oil! The trans still works fine 5000 miles latter.

 

[Mike242GT]

Pablo:

Well, speaking of Volvos, a few years back I needed a wagon and bought a not-so-well maintained '87 245 with 105K miles on it. Leaked from the rear main, had some rust, wiring harness issues, all the usual problems, you name it. But it ran pretty well, the price was right, and like I said, I needed a wagon at the time. No maintainence history, so right after I bought it, I took it to a Jiffy Lube and had the "T-Tech" tranny flush done.

To make a long story short, four years and over fifty thousand miles later, that '87 wagon is still my daily driver and runs like a top. No tranny issues. And yes, I finally replaced the rear main seal.

 

[Dan4510]

Ya'll are really going to hate me. I had a 70 dodge dart sold two years ago that I put 160K on and never touched the tranny. Same fluid that came from the factory.

My 78 volare has the factory fill on its tranny also. clean as bell, shifts perfect. I will not touch it till it needs it.

the key to this is low horsepower and not trying to run rpms to the sky before the gears change.

Also, the first post was full of it about calcium collecting on the clutches and gears. This does not happen, at least in the 50 or so trannies I have torn down. the clutches wear and can no longer take up the slack to engage. Driving a tranny after this point just wears the clutches faster, making the tranny die faster.

I also love my torqueflights in that I can fix one in a day with about $45 of parts and its brand new again. Makes them last lots longer if you put kevlar kickdown band and metal thrust bearing between input and output shaft instead of plastic factory bushing.

Dan

 

[nel]

I can relate to Jsharp's 12 step transmission death cycle:

quote:

---

1. Guy has a slipping tranny, checks oil, notices it's low and/or burnt...etc.

---

Well, at the risk of embarrassment, I'm in the midst of trying to ward off the grim reaper of transmissions.

My wife complained during the 100+ degree weather we had a few weeks ago that the tranny in her car was acting up. It's a 95 BMW station wagon with 136K, and it has one of the worst designs for checking ATF. There's a fill plug in the pan, and you have to check with the ATF at a certain temperature range.

Anyway, I found the fill plug to be leaking--bad crush washer. I drained and refilled (with a new washer, of course) but was too late. Now when the transmission gets warmed up, it slips during the 1-2 and 2-3 shifts. It's seems fine when cold.

I'm now 800 miles into a Neutra treatment (seemed to help, but problem hasn't gone away). Next is AutoRx, followed by Redline High-Temp ATF which has a higher viscosity than normal Dexron III. My goal is to get the tranny to last until next year, recognizing that it may be a futile effort.

If the Redline High Temp doesn't work, I'll have the tranny rebuilt or replaced. The dealer wants $4200 for installing a rebuilt unit with a two year warranty. A local ATRA certified shop wants $3500 for a rebuild. I've checked on the web, and it looks like I could send it off for a rebuild in the MidWest for quite a bit less (shop rates in Northern CA are $90+ per hour). Keeping my fingers crossed...

 

[Jimbo]

My comments on last two posts:

The Torqueflite is my all-time favorite. Bulletproof in the Jeep and several Dodge Vans that we have owned over the years.

My BMW has a stick and I'm glad. I can't believe how they can put an undersized Hydra-matic in a car and charge so much when it breaks. The BMW auto is a GM 4L30E, while the 4L60E in a Chevrolet has twice the torque capacity and costs half as much.

 

[nel]

Suffice it to say that I'm pretty disappointed that the transmission pooped out at 136K.

Anyway, I don't want to detract any further from the original thread. But, if anyone knows more about BMW automatics and what to do, please send me a PM. FWIW, I did have the transmission fluid changed before these problems began, so someone not knowing better could link the two incidents.

I don't blame the new fluid for causing or even accelerating the damage. Rather, it was a bad drain plug washer that resulted in the loss of fluid and subsequent overheating.

 

[Dan4510]

quote:

---

bad drain plug washer that resulted in the loss of fluid and subsequent overheating

---

Overheating the tranny starts an inevitable downhill cycle. First, it makes the seals hard so they cant seal. Second, wear is accelerated since the seals can't hold pressure so the clutches will lock upon the steels, thus slippage occurs futher wearing down the clutch material. As more clutch material is worn down, it accelerates the cycle. Then when enough material is worn, there is no way possible for the clutches to take up enough slack to lock up.

It just continues to go downhill until you have to have it rebuilt. Heat is the #1 enemy. It why on the two slant sixes I have, there is a massive tranny cooler on each one. On the hotrod I have with a tq tranny in it, the cooler is larger since it has to dissipate more heat. I would argue also, this if you use synthetic tranny fluid, it could stand the heat, but the seals probably wont.

Dan