New fluid in high mileage transmissions

I may have some data for an age old question about transmission fluid changes and flushes for high mileage transmissions. I have heard from multiple sources that flushing will cause big problems for a high mileage transmission. My posting here is to warn you that even a small amount of new fluid may cause problems as the detergent in new fluid strips the varnish from the internal parts that facilites its' functioning at high mileage transmission work.

Two months ago, my 5R55E transmission was flaring between gear 2 and 3 and I changed the filter and fixed the flare. To be safe, I put the old transmission fluid back in, after straining it. This prevented me from encountering problems from new fluid which I was warned about.

This weekend, I convinced myself that I should begin upgrading my fluid incrementally since the fluid that is in there probably needs it. So, I siphoned out 2.5 quarts and replaced with 2.5 quarts of MerconV per the owner's manual. Immediately after, I took it out for a test drive and didn't think I was going to make it back home because of the new flare and clattering the transmision.

It is important to note that my transmission was functioning fine without any problems which would be related to loose valve body bolts, solenoids, epc, valve body gasket, broken bands or anything else.

Now, I am left with a transmission wherein the absence of the varnish has created a problem scenario all its own, Realistically, it is safe to say that my problem is not caused by any broken bands, clutches, blown seals or pressure leaks...... since it was running fine before.

Frustrated and befuddled, I added some Lucas transmission fix, but logic doesn't support that may be a solution at all. The bottle says that it cleans and lubricates. If it is cleaning the varnish, then, it may only be complicating my problem.

Moral to ths story: In the words of Kenny Rogers.....
" Promise me Son not to do the things I've Done"
Change your transmission filter and fluid at least once a year. Personally, I intend to siphon/repalce 2 quarts of ATF fluid everytime I change my engine oil to keep the quality of my transmission fluid as new.

If there is a way to flush a transmission with varnish and restore it to its previous condition, we can patent the idea / process and make millions.

Regards,

Stranded

The old fluid won't last forever since its viscosity breaks down. New fluid has a lot of strong detergent ingredients, so I understand what the logic is behind it.

dallasmef said:

If there is a way to flush a transmission with varnish and restore it to its previous condition,

Click to expand...

Huh? Please explain.

Maybe 1qt replacement every 3000 miles or so would be the thing to do.. I have 116,700 or so miles on our tranny in our 2002 Ranger.. I had posted about what the best Brand fluid would be to use and didn't get a reply yet.. I also posted a related tranny question " Drive train slop or tranny issues" Again still no replies.. but Still think I need to do something about my old tranny fluids as far as changing or flushing it goes.. Maybe it's more of a brand specific thing..
dallasmef, What brand tranny fluid did you use? was it Mercon-V? I seen many Mercon -V fluids in reading the bottle that said they were a synthetic blend.. Not Full synthetic fluids.. This was my reason for asking this question about what brand tranny fluid is best for our ageing trannies.. Responses welcome!! George

More of the bad myths continue here. Ignorant people feel free to carry on the bad logic.

I have done it all different ways, and never had any problems after any fluid change. The only problem I have ever had was after installing a VB kit into a VB that came from a burned up trans. Obviously valves were still sticking in that VB, it had nothing to do with clean fluid.

IMO that old fluid myth is crap. If the trans is going to die soon, new fluid won't save it, nor will it cause it. I have not changed the fluid in my 98 trans since I bought the truck 78,000 miles ago. I have just been too lazy to do it this time, I usually do a VB kit, and wanted to wait to do the whole trans. I would not hesitate to change the fluid in it even if it has 176k miles on it. I would do it if I had to take it on a long trip. It would not fail due to any new fluid.

More of the bad myths continue here. Ignorant people feel free to carry on the bad logic.

What brand fluid? Use Mercon V synthetic blend or full synthetic? I have a qt of Castrol Mercon V and it does not state if it's one or the other ... Walmart brand of Mercon V states it's a synthetic blend.. Could this be the cause of some issues after a fluid change.. Also I need to change "flush" my tranny What brand type fluid to use in Mercon V? Synthetic bland or full synthetic ATF what one would be more likly not to cause issues on a high mileage tranny?? Thank you!! George

You could use either one, but the full synthetic is usually more expensive.

Do you know if the original Ford fluid is full synthetic or is a synthetic blend? I think I should go with what ever is closest what is in it.. With all this talk it make me worry.. I have gone over most of the other fluids on the truck already .. With 116,800 miles and me not being the original owner I thought it wise to change it all out.. Thanks for your help!! George

P.S. After thought.. The color of my fluid is not red anymore it's more a yellow amber color.. I checked the fluid after a good long run and it does not appear to have water in it from what I can see nor does it smell burnt.. Would I be better off to just leave it be and not change it?

Take a look at what a bottle of Ford or Motorcraft transmission fluid says. I think it's semi, but I can't say for sure. Most are semi except for some new ones which say full blend. Mobil 1, and Amsoil are good brands that you can't go wrong with. Lubegard makes OEM approved additives if you choose to add something to the fluid.

New fluid = good. Old = bad. Any way you look at this one old burnt fluid will cause your tranny to die..

GeorgeW:
Yes, MerconV. I'm not sure if it is synthetic or not. I just know that is what the owner's manual recommends.

BrooklynBay:
Per our previous exchange, i took your advice that all fluid breaks down and will not last indefinitely. i never let go of that logic and I knew that i had to work in some new fluid.

If I had it to do over again, I might have done 1 pint per week over a period of time instead of a big gulp of 2 quarts working it's way through the transmission all at once. This might have been a better strategy. I dunno. I simplly dunno.

There are litterally endless postings on the internet across various websites where new fluid has caused transmissions to slip immediately after a filter/fluid change and definitely after a flush. That is why I only did the filter change first; and then I changed the 2.5 quarts a few months later.

I remember my Dad used to buy Quaker State engine motor oil that was HD (high detergent). I wonder if anybody makes a transmission fluid that is ND (non-detergent) that will only lubricate the parts; but will not dissolve this residual layer of varnish.

If I had to guess, i would say that the new fluid is preventing the bands from engaging the drum on these trannys that obviously are in working order when they roll into the garage.

The old fluids or debris or what ever words you can use to describe unwanted material in the trans is bad.

If a fluid change occurs right before a trans failure of any kind, the fluid did not cause the failure.

Transmissions do not fail because bad fluid is replaced by good fluid. If there was something wrong with the trans before, and it worked okay with the bad fluid, then the problem should have been fixed. The answer is never to keep the old fluid, not matter what was wrong with the trans or that it worked with the bad fluid.

I don't want any bad parts in my vehicles. I don't want any eminent failure to be masked by another bad part(fluid), and go along merrily thinking that nothing is wrong.

I will not blame a brand new part(fluid in this case) for the failure of another part which was failing and/or going top fail sooner or later. That makes absolutely no sense to hold onto old worn out parts(fluid) because of a fear of discovering an actual failing part.

I want to know about absolutely every defective part in my vehicles at all times, as quickly as possible. Finding or stopping things early is why I basically never break down. My vehicles run forever as long as I am taking care of them my way.

More of the bad myths continue here. Ignorant people feel free to carry on the bad logic.

Dear CDW6212:
With all respect to you........if you can't be nice here......please start your own thread and leave mine alone. My transmission has 209,000 miles on it with no prior issues. In my ignorance, some would say I've done a pretty good job of taking care of it.

The primary topic here is to reflect on numerous postings which relate to high mileage transmissions that fail immediately after a fluid flush or change. Transmission experts describe the condition wherein solvents and detergents in new fluid breaks down the layer of varnish that allows these high mileage trannys to work.

I'm simply promoting conversation to discuss whether there is a way to perpetuate its' continued working under high mileage conditions by gently, incrementally upgrading the fluid without damaging the varnishy layer with large doses of new fluid.

Yes, fine, but you are progressing the concept that magic(you called it varnish) is going on inside of a transmission. I don't know who told you that, but they were wrong to say it, and to call it that.

I guarantee you that if you take your trans apart, and mine with 176k original miles on it(fluid likely also), and a 25k mile trans, the parts will look very much alike. There is no magic film on anything in them, not on the drums, the frictions, the steels, the seals, the bearings, nor the dozens of valve body parts.

I do not mean to belittle the countless people who keep reporting trouble after changing fluid. I only want to stop the future people thinking that the answer for them is to do nothing.

I believe the answer to all automatic transmissions is to be proactive. Replace the fluid(as much as you can get out) with the best that you can buy. Install a valve body kit if one is available, for any vehicle. There are countless upgrade parts, and almost all Ford automatics have existing conditions that can cause or create problems. The VB kits fix almost all of those OEM conditions.

Waiting until a failure by doing little or nothing is a bad solution, IMO. I am done here, I have put forth all of the facts as I know them. Good luck to all,

I too don't understand this varnish coating you refer to.

Listen to what Don is saying, don't jump down his throat, he is just trying to help you and others.

----------------

I normally dont care if subjects are repeated but come on now. This subject has been shot to death.....

I would tend to agree with CDW. I have read through glaciers post and have seen his pics. I have not seen in any of them this so called "varnish". And in any case, why, why, why, would this varnish help?

My brother just had is 130,000 mile tranny flushed, with no ill affects. And it was a Ford. Heresay is not necessarily fact.

Waiting for glacier to post on this issue...

aldive,
I really didn't make this stuff up. Here are some of the postings referencing varnish which prompted this thread. Use your own judgement as to the credibility you give to these sources and their similar positions on high mileage transmissions and the effect of new fluid on varnish and the slippage that results.

http://en.allexperts.com/q/Lincoln-Mercury-Repair-820/transmission-fluid.htm

http://www.rd.com/104259/article104259.html

http://www.trustmymechanic.com/transslip.html

Obviously, i didn't follow the option to "do nothing". And, there were too many examples which advised against doing the flush. I just didn't expect to enounter a slipping problem by only replacing 2.5 quarts of new fluid.

I probably wouldn't pay for a flush but dumping a tranny pan, replacing a filter and refilling is always good.

nitro71 said:

I probably wouldn't pay for a flush but dumping a tranny pan, replacing a filter and refilling is always good.

Click to expand...

Ditto. It's what the manufacturer recommends, for starters, and has worked well for the first 171,000 miles of my Explorer's life. Hopefully it'll continue for a good long while.

However, if you listen to some of the anecdotal evidence presented on this forum and others I frequent, anything over 80,000 miles on this 5R series trans, and you're on borrowed time, because you know, they ALL need to be rebuilt at 80k....