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"cooked" auto tranny?

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78SilvAnniv

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The only reason I am posting this, is because Bud (Rare81) told me this is NOT the bone-head question I thought it to be, and if anyone else is having similar tranny symptoms...it may help to prevent a serious problem and promote a closer look at automatic transmissions.

I have been smelling a 'hot oil' smell that I thought was engine oil, so we changed the PCV valve, but the smell did not go away. No block leaks, no loss of motor oil and I just figured any hot oil smell would be the engine.

It wasn't until I noticed the color of the tranny fluid was no longer red that I suspected the transmission. Of course, I used a 'brown' gas station paper towel...but when I came home I pulled the tranny dipstick and wiped it on a white kitchen paper towel, and it was sure enough brown.
(I check motor oil every other week and the tranny fluid about 1x/month or 6 weeks.)
There has been no difference in the tranny's performance in the 6+ years I've been driving her. Maybe I've caught this in time before permanant damage has occured? Her regular oil change is tomorrow, and I will be asking them to perform a tranny flush and filter change on the tranny, also. I didn't know if a flush would remove all of the bad fluid (I know a torque converter holds a lot of fluid, but was unsure if the tranny would need to be pulled to empty the t.c.) but Bud suggested that a flush would be the best way to be assured of removing all of the bad fluid.

My bone-head questions come next:

What has caused the fluid to turn brown?
Did I 'cook' it?
Is there a contaminant in the fluid?
If the system is flushed and refilled, will it too, turn brown?
What caused this and what can I do to prevent this problem in the future?
Is the tranny cooling system suspect?
Sorry all, I'm just throwing out questions as they come to me...

I have never had any problem with a tranny before now. I have installed a B&M shift kit in a tranny many years ago (it worked just fine, even being installed by a 'girl') but I have no clue as to what to do about this problem.
Am I on the right track with the flush and refill?
What can I do to prevent this in the future?

I am dreading the possible replies of all the things that I have done wrong, and of all the things wrong that could possibly be. But I need to know what I've done, and how to not do it again.
Heidi
 

vigman

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WARNING DO NOT POWER FLUSH

I have a long post around here somewhere, but DO NOT do a power flush..you will be signing the death warrant for your tranny.

Just do a regular service.

Back with more in a minute.

Mike
 

vigman

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More Info 4 U

From ME

Every car I have ever had ( High milage ) that I have had flushed in a little while has started to slip. The brown material in your tranny is usually shedding from the friction clutches. If you remove this it is typically bad news. A tranny flush typically will not include a filter change. I am of the opinion that every 30K drop the pan and just do it that way, droping the pan will also let you know how bad things are inside, Bronze shavings indicate bearings going, dull grey case metal, brown stuff friction material etc. I have had my fair share of tranny problems..... DONT FLUSH, change filters & inspect! Oh and NO ADDITIVES

From Top Down 94

When I got the 94 Convertible, I took it to the dealer for a trans flush, it had 63K miles on it. Their records showed the previous owner had the FLUSH done at 25K and 50K miles. So I just had a fluid and filter change done. He said any dealer database can tell you, if your not the orginal owner, what has been done to the car. Is this true? He also told me the same thing in earlier post in this thread, do not flush if over 75K miles!. However he did tell me that you can change the filter and fluid every 10K miles and get the trans clean over a period of time. This allows the fluid to stay at the right viscosity. Flushing is a shock to the system if not done on a regular basis. As mentioned in earlier post in this thread, it can cause the tranny to start slipping and leaking, this is caused due to the increased pressures building up inside the tranny with the amount of NEW fluid that is put in during a flush . He told me 60% of the orginal fluid in a tranny stays in it during a fluid and filter change, is this true? And if so it stands to reason that if your car is over the 75K miles, more frequent filter and fluid changes will keep it running at its present operating condition, and extend its life. Any thoughts on this type preventive maintenance program would be appreciated. I would like to have mine flushed as well, but am afraid to do so.

From Hib
Ahhhh....be careful in diagnosing the brown material.
When you have automatic transmission fluid that changes from red to brown, the fluid has been overheated. Automatic transmission fluid contains a thermally-sensisitive component in its red dye that turns brown when the fluid has been overheated. ATF that's been overheated begins to oxidize and that oxidation forms solid particles that abrade the metal parts in the transmisison. The dye's change of color is to alert the user that the fluid is oxidized or is oxidizing and needs to be changed.

Now, if you drop the pan and find fragments of brown, gray or black fiberous material stuck to the filter or in the bottom of the pan *that* indicates you have clutch plates that are failing. Also, if you drop the pan and find more than about a dime's worth of fine metal powder, you're probably due for overhaul.
_____________________________
Hib Halverson
 

vigman

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And A repost from C4C5

HI there,
First, normal temps can hit as high as 245-260, depending on if you race autox or not. Normal driving, 230. This goes for any year and model with a torque converter clutch.
As for the changes, my customers are advised, every 2 year or 24k, without exception. There are many reasons for this, and many opinions, however, I like to stand on facts, so here is what is known.
Transmission fluid does many thing within your units. Transfers power within the torque converter, provides cooling to your transmission, shifts gears within the valvebody, AND LUBRICATES.
With this in mind, you must understand that all fluids breakdown over time, and in that, you can never change your fluid too often. The lubrication properties are critical to friction band, clutches, sprags, and bronze bushings within the transmission.
Remember that fluid does almost 85% of the work in the automatics, so you can see, the life of the fluid is critical to the well being of the trans.
If you drive your vehicle hard, and you know who you are, LIKE ME. I change it every year, or 12000. While you can hold to the 75k theory, I can understand why, as varnish is built up within the transmission, you are washing the varnish away, when you change your fluid. However, the more you change your fluid, the less varnish build up there will be, therefore, less chance that your will experience problems.
A last thought on fluids, DO NOT, under any circumstances, use a generic brand of Dexron 3 ATF. These fluids are just above Dexron 3 standards, and will not have the lubricity, or additive packages to correctly work within your transmission for the life of the interval.
With this, as with most everything else, you will get what you pay for.
Besttoyouall, c4c5
 

Yoda

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Re: More Info 4 U

vigman said:
From ME
Every car I have ever had ( High milage ) that I have had flushed in a little while has started to slip. The brown material in your tranny is usually shedding from the friction clutches. If you remove this it is typically bad news. A tranny flush typically will not include a filter change. I am of the opinion that every 30K drop the pan and just do it that way, droping the pan will also let you know how bad things are inside, Bronze shavings indicate bearings going, dull grey case metal, brown stuff friction material etc. I have had my fair share of tranny problems..... DONT FLUSH, change filters & inspect! Oh and NO ADDITIVES

Mike,
I had the auto transmission in my "Splash" pickup flushed at 98,000 miles and serviced with a new filter. The fluid was beginning to turn dark color and the trans was getting a little lazy shifting into 4th, now it is like new.

I changed the filter and oil at about 50,000. Guess I'll see what happens this next 50,000 miles. But, you think I've done her wrong. I sure hope not.

BudD
:w
 

JHL

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I might be missing something here but why would you want to leave a few quarts of the old fluid in the transmission and have it mix with the new fluid.

You wouldn`t leave a quart of your old oil in the pan when you change your engine oil.

J.
 

Dad

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The fluid that is left in is trapped in the torque converter. Some will drill it out and tap it for a small plug so it can be drained. All kinds of reasons you DON'T want to do this just to get the old fluid out. So just change what you can and then do it again at your next oil change.
 

vigman

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The bottom line

An automatic transmission is a delicate device, brimming with all sorts of small control passages. The transmission,over time sheds small bit's of stuff( bronze bearing material, metal shavings from gears, friction material) that are held into place by the varnish that builds up over time or trapped in the filter or linning the inside rim of the torque converter.

The new FLUID has a detergent in it that will clean.. breaking all the old stuff loose to float around again. If you have maintained the transmission ( serviced every 2 years using the pan/filter/top off style) you will have kept the transmission in tip top shape by REMOVING all the bigger bits that get trapped in the filter & the pan.

If the fluid has been sitting in there for the last 4 years... driven hard.. you have a lot of stuff sitting in there which with ALL new fluid, which has a greater cleaning power so more STUFF starts flying around in the fluid.

Typically when a station does a power flush, They do not change the filter. But the fluid changes from Brown to Red... so all the bad
stuff comes out ( or so you think ) but look at the stick a few weeks later...but more so
look at the pan & filter.

You don't get something for nothing, If these things REALLY worked.. do you think AAMCO would go out of busniess?

And how many of these devices do you see at your better transmission shops.

ZERO

Do you not replace the fuel filter when you run a carb or fuel injection cleaner?

New fluid is better than old chemically but its the effects of the clean fluid in the OLD transmission enviroment that are the problem.

It's better to make small corrections that a SHOTGUN approach ( unless your totally replacing the trans.)

Mike
 

JHL

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Vigman,

I appreciate what you are saying , I ALWAYS change filters. I would be surprised at any shop over here changing fluids that did not change the filters. It kind of defeats the purpose if you are going leave the old filter in place. Maybe I am misunderstanding what is involved in a "power flush". I assumed that flushing should purge the tranny of any particals floating around before it is refilled with new fluid. If you just get fluid pumped through untill clean stuff come out the other end this is not a proper job.

Auto transmissions are not as common here in the UK but the last time I had a car`s auto trans fluid changed they flushed it and replaced the fluid and filter. I wouldn`t have expected them to do anything less. I had none of the problems you describe after it was done. The car was a Jaguar with a GM400 tranny and about 90,000 miles when I had it done, it continued to run for many more miles and never missed a shift.

What I should have said in my last post was that you wouldn`t leave a quart of old oil in the pan and the old filter in place when you change your oil.

J.
 

vigman

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Most places in the states....

( read Jiffy lube.. or any quikie style oil change place)

Will hook you up outside the bay and couple their pump to the radiator tranny cooling line.

They start the pump, they start your car and input the new fluid as fast as the tranny can pump it out.

Usually 22 qts of CHEAP ATF are used in this process ( for 55.00 to 75.00 dollars) .

They unhook, top the tranny off, and away you go.

Now a note here.

Not every case is the same.
But I prefer to err on the side of caution.

Most of the TECH's at the quickie lube places (and I use that word loosely) use the word DUDE or KEWL KAR every third word. and cannot tell the difference between a flare wrench and a cresent.

I have NEVER had a tranny survive the process ( in a 2-3 week window)
BUT
Most of my cars were older, abused, junk yard dogs.. that I nursed back to health.

Like my 88

It was barely running when I got it.
I had it flushed. ( 102k on the orig trans fluid)
It died.
I got hosed on the tranny rebuild.
( but applied SO much pressure via legal action the guy left the state.. some measure of satisfaction there.. but I still had a bad tranny after 4 attempts for him to rebuild it)

You get what you pay for.
I tried to get out cheap..
I paid dearly in the end.
and have dealt with some GREAT Tranny mechanics.. who have advised they LOVE to see cars hooked up to that beast..
it's job security for them.

Mike
 
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Mike,

You have expressed my opinion on tranny flushing perfectly. Many, almost all the oil change shops, neglect to change the filter because it involves dropping the pan. The contents left in the pan in MHO tell the real truth as to the condition of the transmission. A small amount of fine sludge (a tablespoon or two) is normal and expected, even if you change the fluid and filter every 30k miles as I do. Brass fillings, or gear chunks are not normal and not good. While I agree with JHL comments on leaving some of oil behind, it really is the only right way to service a transmission. The flush has caused more failed transmissions that I'm aware of than it's helped. Regular fluid and filter changes @30k miles is the only way that I know of to assure a healthy tranny.
 

Dad

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First off I agree that you remove the pan and replace the filter. The thing I think is being missed here is that by this method you do not drain out all of the fluid, the torque converter is still carrying a normal amount of the old fluid in it. As far as I know there are 2 way to "drain" all of the fluid, 1) Take the transmission out and then drain the loose converter. 2) Drill the converter body and let the fluid drain out, tap the hole an put a plug in it. Then hope you didn't add some drill shavings to the inside of your transmission.

If any one can tell me a better way I'm all for it, but other than the above the transmission will have old fluid in with the new.
 
R

resto75

Guest
power flush

I had the trans in my 91 ford p'/u power flushed at 72,000 mi and the filter changed by a reputable private trans shop who has a good reputation. Never had a problem since then.
 

vigman

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Drilling the torque converter

The plug will change the balance. Now I have see some after market setup's like that which have a bung for the new threaded fitting and are balanced with that in mind.

To do it yourself ( unless your a machine head) I think...... is asking for trouble.
IMHO

If you have a neglected or old tranny you should up the service intervals.The continued frequent maintance will also give you a good excuse to get the car in the air and check for other gremlins.

Mike
 

Dad

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Drilling the torque converter

The plug will change the balance. Now I have see some after market setup's like that which have a bung for the new threaded fitting and are balanced with that in mind.

Not so, the plug is an aluminum shocket driven plug with heat activated sealer on the threads. Still should only be used by a, as you put it, "machine head", of which I agree.
 

vigman

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Dad

While cruzin thru my fav wrecking yard, I have seen a LOT of botched attempts from backyard mechanics.You & I are in agreement, a competent person with the nessesary skills & tools should do this job.

If the owner feels it's nessesary.

Personally, I would pay for 3 filter changes over a 1,500 mile period then to drill into the converter.

At least that way I could get an idea of how much junk I was removing and if more was being generated.

Heck a properly installed trans cooler would do a lot for an older car.

The converter that stuck in my mind was a guy used a hole saw and JAMMED a cast iron plumbing plug 1/2 inch into the side of the converter complete with J&B weld. The square bit on the top was scraped down a fair amount.. and it looked pretty fresh and I don't think it was from grinding BEFORE the engine was fired up.

I laughed my A$$ off then noticed a 5 degree tweek on top of that.

The things people will do.


Mike
 

vigman

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But back to the orig post

Heidi,

Things just happen, wear & tear, milage, outside temps, junk in the radiator.

I do not see in your post where you have done something wrong. It's just it's time & use.

Mike
 

Dad

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Vigman - LOL

If it was a high pressure square drive 1/2 it could have lifted the wheels off the ground at highway speed.

I have a friend that rebuilds converters and if you think you've seen some junk or weird fixes -- that's another story. May be we should start a thread about some obvious no-no's or the dumbest repairs. Or just weird/crazy things we see in the driving world.

What do you think out there?
 

vigman

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I agree

Bad Ju-Ju aka Bubbaville


AND including misinformational posts from dealers, parts guys,service companys etc.

That would be a hoot!

plus a sub cat what's the cheesiest repair that you have had to do ( and will admit it)

Mike
 
7

78SilvAnniv

Guest
tranny update

Just to let you blokes know, we're gonna do this one ourselves!

I have received advice from two people I trust who are both Master Techs and certified ASE in transmissions, don't know each other and gave me the same advice.

We will be installing a drain plug on the tranny pan and over the course of several months, draining and replenishing the fluid every other week until it becomes a clear red. We will not be performing a tranny flush, however we will flush the lines and cooler.

Both of these mechanics suggested that the tranny-flush-failure phenomenon occurs mostly with older vehicles, vehicles not properly maintained or vehicles with trannys on their last legs and the tranny flush is the owners last ditch effort to save the tranny, but it ends up becoming it's death knell.
With trannys in these conditions that are taken to quick-lube places, many times they don't drop the pan to remove the sludge, and the filter can become clogged with that sludge that has now been forced into the filter screen.

I'll keep you updated on how the process goes. We're planning on tackling this mid-week. Bought a case of tranny fluid today in preparation.
Heidi
 

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