transmission flush/fluid change

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wagoneer

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gonna be driving some 9k miles between october and february. Tranny fluid looks a bit used and wanting some "rule of thumb" advice it's a big ford 2001 E350 usually with a big load.
 
If it were mine I would change fluid and filter. I wont be surprised by how many disagree on this forum. But, if a fluid change kills your transmission, it wasn't going to go much further with out the change.
 
Do a pan drop, a filter change and a refill.

This will get less than half the fluid though.

A "flush" does not require the shop drop the pan and change the filter. A 'flush' might clog the filter. A flush could cause transmission failure. A flush followed by a pan drop and filter change is acceptable, but nowhere actually does this.

I recommend having a drain plug installed in the transmission pan when it is off. This way after the pan drop/ filter change, one can easily drop ~4 more quarts and replace them.

Use only the manufacturer specified fluid. Many transmission shops have a universal bulk fluid to which they add a supplement which is supposed to make the fluid match the characteristics of the recommended fluid.

In cases of Dodges, where the recommended fluid is ATF+4, which is synthetic, the universal bulk fluid and an additive is a true disservice to the transmission and will cause failure at some point.
 
So I'm about to do the whole deal starting with a 5 minute chemical flush then drain, drop pan, change filter and then the system flush. But researching it is a bit dizzying cuz it's amazing all the conflicting information out there.

First there's the school of thought that says if you don't know when/if it's been flushed, then don't because it could damage or kill your tranny. Some even suggest that if it's high mileage and hasn't been changed, then don't change the transmission fluid because doing so could loosen up sludge/varnish and then cause damage. This sounds ridiculous to me, but it's funny how many people promote this.

Some also say that if it's high mileage, then best not to switch from regular to synthetic because it'll cause leaks, any thoughts on that one?

Others say that this is old school thinking and that with the newer fluids this isn't a problem and that you should always flush and change the ATF on a vehicle if you don't know when or if it was ever done in the past. I like this idea as it sounds better to make sure it's as clean as possible when you become the new operator, start with a clean slate as it were.

Unfortunately I don't have the original service records for my E450, so I have no idea how many miles are on the current transmission, but odometer says over 250,000 - anyone think it's possible that it could be the original (it was a city transit bus in Des Moines, IA, pretty flat country so don't imagine it was stressed much, if it was driven properly of course). Seems to drive/shift good, although there may be a bit of hesitation getting into 3rd (haven't really driven her enough to be sure). Also no idea when the fluids were last changed, but the tranny fluid looks kinda brown:s

So I'm about to buy some Pennzoil 550035073 Synthetic Multi-Vehicle Automatic Transmission Fluid (says it's rated for Mercon V which is what my 4R100 tranny needs) on Amazon, amazingly cheap for synthetic at $66 for 12 quarts. I haven't been able to find out any feedback or reviews on this product anywhere, so that worries me, cuz it's either too new (untested?) or... well can't think of any other reason why there's no user info out there.:huh: Pennzoil's a decent brand so I would think that they wouldn't put out a bad product, but who knows, anybody else ever use this stuff?
 
I personally would not use a multi vehicle transmission fluid even if it was applicable to my Van, which it is not. Pennzoil is a good outfit but I just think a multivehicle formula is an average compromise to just barely fit the widest specs listed by each manufacturer. Marketing for pennzoil's bottom line does not mean best for any specific application.

They Synthetic causing leaks myth is rooted in fact, from the 70's when Mobil 1 had some ingredient in their synthetic engine oils that were damaging to gaskets, and 40 years later we still get the synthetic causes leaks myth promoted time and again, over and over.

Now with engine oils, synthetic oils clean better than conventional oils. The synthetic can remove gunk which was sealing the gaskets from within, so it is a chicken or the egg thing. The leaks were there, the synthetic revealed them, but is not the cause of them, but the end result is the same, if it does indeed reveal leaks.

I have never heard about synthetic transmission fluid causing/revealing leaks, only engine oils. Heat is what destroys tranny fluid and once it is compromised, it becomes a ticking time bomb. Synthetic transmission fluid is much more heat tolerant. Adding an additional transmission cooler, using a spec'd synthetic transmission fluid and a regular refreshing of fluid, not necessarily a complete flush, is the best way to get the most life from a transmission and it is more effective the earlier it is done in a transmission's life.

I'd avoid any solvent based flush type product. Just drop the pan, add a drain plug, change the fluid and filter and use Mercon whatever that Ford Recommends/ back specs for that particular transmission.

I've also added an inline Magnefine transmission filter which filters particles to a much finer degree than the filter in the pan, which is described more as a Rock catcher for particles 100 microns and bigger where the Magafine filer media is 30 microns iirc, and of course the magnet which can catch ferrous particles much smaller than that. It has a bypass valve if it gets clogged, but one must be sure to install it in the correct direction for the bypass to work.

I'd worry more about that leaking pinion bearing seal and possible low fluid level in the differential, as a new axle, rebuilding and axle, or even a junkyard axle is extremely expensive, and Differentials tend to be ignored until they start howling or whirring..

I know getting out all the old fluid via a "flush" is, on paper, more desirable than just replacing portions of it with a pan drop, but unless the filter in the pan is changed it can just cause issues.

If you want a belt and suspenders type transmission maintenance strategy, do the solvent, then the flush/Fluid exchange, then drop the pan, change the filter, install a drain plug in the pan, refill with a high quality synthetic, and add a large Hayden transmission cooler inline with the likely already existing external cooler, which is also inline with a cooler within the radiator.

Using the OD off button when climbing grades will help keep the fluid cooler too, even if the engine has enough power to climb the grade in overdrive.

Some advocate letting the transmission choose which gear is always best for it, but I equate this to the government telling me that driving 65MPH in the left lane is always best for everybody everywhere, and the left lane dawdlers are doing a service to humanity by being ignorant douches and obstructing traffic flow.
 
what I have found is if your trans has been ignored and the fluid is brown and smells burnt doing a filter and fluid exchanged will cause it to fail. however if your trans is that bad it will fail soon enough anyway there is nothing you can do to stop this. so the question becomes how bad is it? I nor anybody else can answer this over the internet. if you don't know somebody you trust that can look at it, I would go ahead with the filter and fluid but use regular fluid not synthetic(save a couple of bucks now). if the trans makes it to the next service interval go ahead with the synthetic. stay away from the "mechanic in a can" type of stuff it's all snake oil. like stern said coolers(the biggest one you can afford) and a external filter are great additions. the thing about only using od when you need it is also great advice. around town and climbing/descending grades turn it off. highdesertranger
 
" stay away from the "mechanic in a can" type of stuff it's all snake oil. "
It is not! Just make sure to use the product that says "magic" some place on the label.
Oh ya. If it makes your transmission better, your trans will soon fail.
 
I , personally, do not like Pennzoil products...I'm a Castrol guy. (but that's just me)

I do, however, completely agree 100% with the others who say "Stick to whatever oil the manufacturer specifies", and do NOT use a multi-grade or vehicle oil.

Your rig ain't worth the risk.
 
Just got my transmission fluid changed in my van yesterday at Pennzoil lol! There wasn't any red tint left in the fluid when I bought it, my thoughts are if it takes a crap on me while I'm saving to leave in January, better now than in the middle of nowhere! :)
 
I am going through this same process now. I talked with service manager that I have totally trusted in the past about the flush versus fluid filter only and he said absolutely to flush. I was going to let them change oil also since I was in a hurry and made an appointment to bring it in the morning I was leaving town. He quoted $300.00 or slightly higher and sounded like way overpriced.

I called AAMCO that I don't always trust as they have a lot of turnover in personnel from manager on down but the guy I talked with said definitely not to flush.

I called another transmission shop with a superb reputation and he said the same thing at least to start with.
He worked me in and dropped the pan cleaned it replace the filter, gasket, partial new fluid. Told me the torque converter was the week link in my chevy transmission and usually started the problems. He said drive it for 30 days and if it was acting OK he would do a flush and both jobs together for less than the first shop quoted for the flush and oil change. He did say I should start saving for a rebuild that would cost around $1500-1600.

700 miles later including over 2 hours of very hard mountain miles and the transmission seems OK to me.

I guess I will let him do the flush when I get back if it makes it back. Or I could do several fluid changes myself also.
A SEEKER
 
A SEEKER said:
I talked with service manager that I have totally trusted in the past about the flush versus fluid filter only and he said absolutely to flush.

They sometimes are first and foremost salesman. You don't say how old and how many miles your vehicle has on it or if you have service records and know how it was maintained by the previous owner(s). From what I've seen on several different forums, this makes all the difference in the world.
 
This discussion mirrors others I've read on several forums, and as Seeker points out, even among trained professionals there are completely opposing opinions, and knowing a bit about human nature it's actually not so difficult to understand. Let's try resorting to a mixture of common sense and logic.

First off, is it probable that two completely opposite outcomes can occur from the same event? Can changing the fluid (and I'll be using the example of a complete flush and fluid change) in an older transmission be both good and bad for it? Of course my initial reaction is no, it is either one or the other, but as I've said I'm no mechanic, but I do have good mechanical skills, and a some considerable experience over years of working with lots of different tools and machinery which can be applied towards deducing which is most likely the truth (at least as far as my knowledge can help me to ascertain ;?). :s

Backing up a bit, lets take a look at the characteristics of lubricants in general: 1)Reduces friction 2) Transfers heat 3)Prevents oxidation/corrosion 4)Carries away contaminants and debris 5)Protects against wear 6)Reduces energy loss/improve efficiency (as applied to mpg for instance).

Wikipedia says this about ATF's:
Most ATFs contain some combination of additives that improve lubricating qualities,[2][3][4] such as anti-wear additives, rust and corrosion inhibitors, detergents, dispersants and surfactants (which protect and clean metal surfaces); kinematic viscosity and viscosity index improvers and modifiers, seal swell additives and agents (which extend the rotational speed range and temperature range of the additives' application); anti-foam additives and anti-oxidation compounds to inhibit oxidation and "boil-off"[5] (which extends the life of the additives' application); cold-flow improvers, high-temperature thickeners, gasket conditioners, pour point depressant and petroleum dye. All ATFs contain friction modifiers, except for those ATFs... that specifically excludes the addition of friction modifiers.[8] According to the same leading oil distributor, the M2C-33 G specification requires fluids which provide improved shear resistance and oxidation protection, better low-temperature fluidity, better EP (extreme pressure) properties and additional seal tests over and above M2C-33 F quality fluids.

So now for the logic part. Which fluid possesses more of the aforementioned properties, new transmission fluid or old? Which is more likely to reduce friction, disperse heat, prevent corrosion and transport away debris and contaminants? Well I don't think it takes a genius to understand that old/dirty ATF cannot compete with new/clean ATF, so there's ZERO sense in the idea that the old fluid can in any way be better for your transmission than new.

So the next step is to consider if it is possible for new ATF to do actual harm to your transmission. Obviously it's not going to damage the actual components, but as far as I can tell one major argument is that the new ATF will break down sludge/varnish/contaminants, and these will do the damage, clogging orifices/lines leading to failure. On a certain level this sounds like it could make sense, but lets examine this more closely. This argument hinges on whether or not clean ATF actually does what proponents of this idea say it does, i.e. causes chunks or at least sizable enough particles of contaminants to break loose, circulate throughout the system and then create clogs that can cause a breakdown.

This is where my knowledge breaks down, I don't know much about the internal mechanics inside a transmission - tore apart the tranny on my '69 T-Bird when I was 19, and that was enough to teach me never to try that again (ended up bagging all the parts, putting them in the trunk, and practically giving the car away, lol). I have however seen how dirty an old, filthy tranny can get, but save for those really poorly maintained ones, I'm wondering if that's more the exception than the rule. :huh:

I do wonder if there's been any kind of study done on this - could you take some old sludgy, gunked up parts and put them in a bucket of new ATF, and then wait and see what happens? I could definitely see how a lot of it would dissolve into the new fluid, but will some more solid pieces break loose intact? Without being able to prove or disprove this theory, I'll admit that it's a possibility.

So if you were to take a sample of say 100 older vehicles, after changing the ATF in them the outcome will be that some transmissions perform well while others fail, that is a fact. I have no idea of what the ratio would be, but then that might not matter because since each and every one has been driven, maintained and overall treated differently there's really no way to be sure exactly what caused the failure, I would think, unless you could do a complete in depth "autotopsy" :p But if it fails shortly after the fluid change, you can bet your bottom dollar that those people will be inclined to blame the new fluid ESPECIALLY if they (or more likely their mechanic) has heard of this theory before. In those instances it becomes a self-fulfilling proficy as it were, but it's also an example of faulty reasoning connecting two dots that may not have any relation to one another. A failed transmission after a full flush/change does NOT automatically:D mean it's the fault of the change itself.

And if you took another 100 said vehicles that you didn't change the fluid on, while I'm certain more would fail than not, when they don't fail those people (or their mechanics) will be all too quick to point out that the reason they didn't was precisely because they DIDN'T change the fluid, using the same faulty logic. And for all those that did fail, well hey they were old and probably going to fail anyway, lol, so imo that's how these kinds of theories gain legitimacy. And while I could be completely full of bull manure :p, all things being equal, logic tells me that given what we know about the advantages of new ATF versus old, that the odds are ultimately in favor of changing the fluids. Yes there may be risks with doing the change, but leave in the old and it's a certainty that you'll increase the wear and tear, reduce what life there is left in the transmission and increase the odds of a major breakdown in all likelihood. So that's my theory and I'm stickin to it, unless of course there are some facts that prove me wrong, in which case I'll gladly switch sides, lol. :D:D:D
 
Of all those properties listed at Wiki the frictional properties of old vs. new may give more of a clue as to why a flush might cause an old tranny to fail. They're automatics but they still have clutches and on one forum (I didn't save the URL) it was explained that an old tranny sort of 'gets used to' the old,gritty ATF and when it is replaced with new fluid then slippage,heat and failure can occur.
 
While the age of the transmission might mean a difference in build or components which could be affected, what I'm talking about is addressing whether or not flushing is good or bad in general and try and keep within the scope of that issue.
Also that explanation, imo, just doesn't make sense when applied to machines - a transmission doesn't "get used to" dirty, worn out, old fluids that aren't doing what they're designed to do, (especially not dissipating heat, no way old fluid is going to be better at this than new). Again, I not saying that new ATF can't cause a failure in an old transmission, but there has to be some other mechanism/process at work.

One explanation is that over time the material that helps the clutches grip gets worn off and suspended in the fluid and that eventually it is this stuff in suspension that's keeping the tranny working. Then when you flush it out, the disks can't grip and so slip and fail. While this again seems, on the surface, a plausible explanation, I'm not really sure it passes the acid test. If your tranny fluid has got so much friction causing material floating around in it, it's highly unlikely that it's going to be able to do it's other main jobs, that of lubricating which REDUCES friction, heat, wear etc.

That said, there does seem to be some agreement that IF a serious problem already exists then it's best not to change fluids, as quoted here,

"Before draining or flushing you should pull the dip stick and look at the fluid. If it is dark, burnt smelling, and you see little flakes or speck in it, DO NOT FLUSH IT. The fluid and transmission possibly has hard partdamage, but the transmission just has not figured out it should die yet. If you flush a transmission in this condition it could fail right away. Real strange, but that is what seems to happen."

So this makes some sense, and I'm guessing that this is the reason many transmission shops and mechanics keep perpetuating the idea that flushes are bad for older/neglected transmissions. Because they could be held financially responsible and/or have their reputations damaged by angry customers badmouthing them all over the internet, they're understandably gun-shy and use this excuse as a reason for their unwillingness to perform them (and also as a way to push customers into more expensive rebuilds I suspect in many cases).

Here's one more great comment by a seasoned professional which sums up what I've been thinking all along,

"Anyone who is even remotely involved with cars has heard this type of story- someone that they know got a transmission flush and their transmission failed within weeks or even days.

The urban legend behind this is that the "sludge" is all that was holding the transmission together and once it was removed with a flush, the transmission had no chance of surviving.

The story goes like this:
Jim was having a transmission problem, let's say that it was sluggish in the morning and would slip on take-off from a stop from time to time when it was hot out.

Jim takes his car to the local lube place for a flush and an engine oil change while it's there. Jim gets his transmission flush, pays and goes on his way.

At first, he notices maybe a slight improvement in performance but his transmission is still exhibiting most of the original symptoms.

About two weeks later Jim is driving to work and he stops to pay a toll. When he tries to pull away from the toll booth the unthinkable happens- the car just revs and goes nowhere, as if it is in neutral. Jim moves the shifter into low and is able to limp his car off to the side of the road and wait for a tow truck to take him to a transmission shop.

What happened?

Here's a list of reasons why the transmission flush myth exists:

The myth is propagated by people who claim to be experts. I have even heard of transmission repair shops who contribute to the myth in the hopes of scaring potential customers into having their transmission overhauled rather than maintaining it.

There are thousands of "internet experts" who promote the misinformation- it's truly a case of "monkey see, monkey do" on steroids!


There may have been a time in the early days of automatic transmissions when failure after a flush was more common, perhaps because of antiquated friction material and transmission fluid technology during the 1950's and 60's but this was before my time so I'm not able to truly discuss the legitimacy of the possibility. I can, however, say with certainty that it's not an issue with 99.9% of the vehicles in service today. If your owner's manual is in the glove box and not painted on the wall of a cave, you are probably good to go.

"Sludge" is all that was holding the transmission together and when it gets cleaned out the trans in going to fail immediately. Guess what? If you have that much sludge in your transmission, it's already bad and in need of a repair.

Once in a while a flush is performed, usually at a quick lube operation, and the transmission is not refilled correctly- resulting in failure soon thereafter. Of course the incorrect fluid level is not recognized as the culprit- the transmission flush is! Many automatic transmissions have fairly complicated fluid level checking and filling procedures that are best left to a transmission repair expert to perform.

People have unrealistic expectations. A transmission flush is no more likely to fix a failing transmission than an engine oil change is to fix a major internal engine problem. Both of these things are great to do regularly but they are maintenance- not a fix for a problem.

The reality is that most people don't think about their transmissions until the day that they have a problem. Jim's transmission was on borrowed time- it was going to fail anyway but now that it has, he is going to perpetuate the myth. If he ever hears someone mention a transmission flush, he's going to proclaim, "I had that done and my transmission blew up within a month!"

I have been in the transmission repair industry since 1987 and can honestly say that I can't recall a single time where I saw a healthy transmission get a flush or a fluid change and subsequently have a problem. A transmission flush is the best maintenance that one can do to extend the life of your automatic transmission, don't miss out on the benefits because of the nonsense that exists surrounding changing your transmission fluid!

Anyone can feel free to repost this as long as you leave the "about the author" part intact.

About the author:
John Lombardo is co-owner of <a href="http://www.importperformancetrans.com">IPT Performance Transmissions</a> and has been in the high performance industry for over 25 years
.
"
 
well here is something to chew on. if your tranny fluid is burnt this means your clutches and steels are burnt. the old dirty fluid is carrying this material in suspension taking up some of the tolerances in the clutch packs. remove the dirty fluid add new and this material is no longer in the fluid taking up the wear in the clutch packs. so the trans starts to slip. once that starts it not long till he end. like I said before if your trans is at this point it will not last long no matter if you change or don't. that's why I said not to do a complete flush but a filter and partial change with the regular fluid(non synthetic). to see what happens if the trans is going to fail no reason to dump 100 bucks of syn fluid in it. highdesertranger


so I tried to edit but took to long. that guy that luis quoted says "I can't recall a single time where I saw a healthy transmission get a flush or a fluid change and subsequently have a problem." so he is even doing the cya with the "healthy transmission" phrase. well of course it's not going to hurt a healthy trans, we are not talking about a healthy trans, a healthy trans does not have burnt fluid. highdesertranger
 
Yeah I figured that's what it sounded like too, lol. On the other hand, if flushing the fluid does end up uncovering a major problem, I guess I'd rather find out now, long before I actually decide to go full-time. That way I still have a job and can afford to replace the tranny. I'd hate to have it fail after making the transition, and leave me stranded possibly in the middle of nowhere, on a mountain side, at night, in -20 degree weather, and with a pack of hungry wolves outside.... well it could happen:blush:
 
mind you I wasn't saying what he said was wrong, but he was talking like a politician, out both sides of his mouth. luis if I remember right your van has 250,000 miles mas o menos. if the fluid is burnt and you have the money now I would just go ahead and do the trans now. but that's just me, that's how I do things. do the repair before it blows up. if you wait until the trans gives up the ghost it usually makes the repair more expensive. you would be good for another 300,000+ or more if you get a quality job with any upgrades that are needed, like the biggest cooler or 2 available, remote filter, etc. highdesertranger
 
These posts are just too long to read through.
If your transmission is so worn as to need old burnt out dirty fluid to function, do you think you should drive further than the local grocery store? Don't buy more food than you can carry home from the break down on the side of the road.
My advice, get the transmission flushed of all old fluid, then get the pan dropped and new filter and refill fluid. Drive for 1000 miles and then decide if you want to be on the hyway.
If your transmission can't handle the new fluid, what about all the rest of the drive train and wheel bearings?
The only reason to not change the fluid is if you are going to replace or rebuild the transmission before you drive away.
i can't fagted say no more.
 

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