Bad idea to change trans fluid on older truck?

[Ranger5.0]

ranger i was being sarcastic in my first few sentances lol. And straining it is not messy at all. Just put your pan under the oil tank, but a strainer over the drain plug, and while its draining into the pan its also being filtered. When its done being drained just dump whats in the pan back into the motor. AGAIN, im being sarcastic lol. Dont actually do that.

Hey man, i know, i was being sarcastic with my response to what you said. I forgot to seperate the sentance from the rest of it lol...sorry bro. So, you say this oil straining process works eh? You know, if you ran synthetic, plus strained it and changed the filter every 5000 miles, you would never need to actualy replace the oil

 

[michowski]

Exactly man. But dont tell anyone this. Its a dealer secret and were not supposed to know this info. Also I heard a little bit of water helps as well. Helps break down the oil and make it thinner so it can better get in your seals and inbetween really hard to get to parts.

 

[eli]

Its not the problem of grit clogging the pump, its the fact that older trans clutches get used to the the coefficant of friction from the broken down trans fluid, when you put in the new fluid in it has a higher cofficant of friction and startes to wear hard on the clutches. The clutches then tear apart. After all the clutches in a factory tranny of pretty much compressed paper. That is why most shops don't do tranny flush after certain mileage, and fluid clolor

 

[MAKG]

There is another reason why shops might not want to service a transmission with burnt fluid (which comes from a transmission that is ALREADY SLIPPING) or a lot of miles: People blame the shop for the subsequent failure, without realizing it would have failed anyway.

A transmission with burnt fluid HAS ALREADY failed. Why would you then expose yourself to claims when the owner tries to blame you for it?

 

[Ranger5.0]

There is another reason why shops might not want to service a transmission with burnt fluid (which comes from a transmission that is ALREADY SLIPPING) or a lot of miles: People blame the shop for the subsequent failure, without realizing it would have failed anyway.

A transmission with burnt fluid HAS ALREADY failed. Why would you then expose yourself to claims when the owner tries to blame you for it?

I was waiting for somone else to chime in and say that. THATS exactly why we do oil sampling and when somthing shows up, we sit the owner down and give him the "fix it now and save money by salvaging some parts, or wait till it fails and spend 15grand on a rebuilt unit"

 

[Bent Bolt]

There are so many myths running around out there. #1 reason that the "don't flush a trans with high miles/ VARNISHED atf" is that varnish. That is what happens to ATF if it is OVERHEATED. It literally cooks itself. That varnish sticks to everything and can be quite hard. If you try to flush the trans with new ATF, the detergents in the new ATF can dislodge the varnish which can hang up the shift valves.It can lead to failure because most people will keep on driving untill it fails.
That or the trans was failing to begin with because the owner was neglecting maintenance in the first place.

One more thing that nobody has brought up. The chemical flush that is part of most flushes. The company's say its OK but I'm not so sure. It's some sort of solvent, it can clean grease and oil off my bench. I won't put it in any trans I am servicing.

I mean , if the ATF is somewhat red, it's doing OK. Do the service and forget about it. If it's burnt, ---even a little bit -- the trans is slipping and no amount of preventative service is not going to "fix" it.

 

[4x4RangerGuy]

michowski- Ive heard of that oil, i cant aford it tho, and straining it gets messy hahahahaha Oh, and btw, I have actualy seen many automotice torque converters with drain plugs. Guess once you work on enough krap you see stuff like that. SO, now we are saying the charge pump failed, yet it still shifted fine. Well that cant be true as that pump supplys the oil to either apply the break band or clutch packs depending on which gear it is in. so if the pump was starving for oil due to that clog you speak of, then, it would have a hard time building suficent presure in the servo or in the clutch apply piston. the symptoms of this would be, lazy shifting, sliping clutchs trany runing at abnormaly high temp. Also, when working with the "therory" that grit in the oil is good, how do you think the pump would like all this "grit" being pumped through it. Now, lets think about this, sandblaster spray "grit" at high pressure to strip what ever it is we need striped, note, it doesnt work well on girls. Now, lets move to the trany, we take the grit, it comes into the pump at low pressure, and leaves the pump at a max of i THINK 125psi. i could be wrong on the pressure, i will have to check my notes. Anyways, this oil and grit is not blasting out of the pump, the grit will obviously be coming into contact with important stuff in the trany. Stuff like shift valves, grit in there will cause a lot of wear, and considering they are a laped fit, any amount of wear will cause them to leak. Now, solinoid operated shift valves, they use electromagnatisem to control oil flow, is this grit is magnetic, then its going to collect around these valves, causing them to be "gumed up" or jam open, or closed. now, some of this oil is routed to the apply pistons, do you thing the rubber orings in there like having small particals rubing against them? no, thats how o rings die...dead o rings mean less then adaquit clutch apply pressures, which leads to clutch slipage, which causes MORE GRIT. Now, the cycle repeats its self. Saying the grint in a trany is good is like saying the small particals of metal caused from normal wear in the engine is good, and to not change the engine oil. but most ppl are more educated when it comes to engines, they know that if you dont regulary get that grit out, it will imbed in the bearings, and over time, start scoring rotating parts. think about it. stop going by what that guy said that day when you were at that shop. I dont care if anyone hear flush's tranys or changes there oil. Infact, the less people take care of there stuff, the more work there is for me.

Too bad it is true. The thing exhibited no shift issues whatsoever, whether you like it or not. The pump just went. A big bang, and that was it. I will attribute it to the flushing that I did, and as such, I will not recommend it on older vehicles that have not had a proper service record. I do not want to be held liable even when I tell the owner there is a chance this will not help.

If I was going to trust anyone's opinion on automatic transmissions in this thread, it would be Bent Bolt. He knows what he's talking about from his past posts, and its obvious he works on them all day.

Also, I'm not going to stop listening to the guy that rebuilds all my transmissions for my customers. I have not had a single customer come back and complain about my rebuilder's work. He does excellent work, and he knows what he's talking about, no matter how much you think you know.

 

[Ranger5.0]

how much i think i know? I work for John Deere, and have rebuilt MANY powershift tranys. If you know what a powershit it, then you should be able to relate an automotive type trany to them. they use the same principals. But un like in the auto world, if one of our rebuilds goes bad then there is hell to pay. The customer is pissed cuz hes got a 300 000 doller paper weight out on the job that wont move. so hes losing money. then he calls the owner os the shop, then it just rolls down hill from there. I dont like or dislike your explination of how said trany acted befor failure, odds are, you were paying close enough attention. Its not rocket science, what did the pump its self look like? after all the work was done on it, was anything checked to make sure it was actualy good to go? by the sounds of it, no or your little "trany went bang and no worky no more" wouldnt have happened. As far as liability goes, when it comes to customers, i dont give an opinion, thats not my job, thats what the service managet does. When it comes to this, there is no liability. People anything read on the internet needs to be taken with a grane of salt, and have some common sense applied to it. Its basic hydraulic principals. if any pump starves for oil, it will over heat, and sieze up. That being said, at the same time, if its supposed to be pumping out 10gmp but has a restruction on the intake side, then it will never meet the flow required to properly operate other functions within the trany. That means, transoperation would suffer. WHAT did the pump drive shaft look like?

 

[Bent Bolt]

how much i think i know? I work for John Deere, and have rebuilt MANY powershift tranys. If you know what a powershit it, then you should be able to relate an automotive type trany to them. they use the same principals. But un like in the auto world, if one of our rebuilds goes bad then there is hell to pay. The customer is pissed cuz hes got a 300 000 doller paper weight out on the job that wont move.

You think I don't get crap when things go wrong?? Quite the opposite. Differance is I shove the crap back. If it's something stupid I did, I'm man enough to admit it and take care of the problem. If it's a parts failure ,I still take care of the problem but I will not take crap from the customer or managment. Period.

It's good to have job security !!!

 

[Ranger5.0]

thats the difference between working on a 2000 trany, and a 15000 trany. With your therory of fresh atf lossening varnish, then its a bad idea to even change the ATF and filter? What hapens when the filter gets cloged by this "good grit" ? it starves the pump, then, trany death folows. When trany fluid age's, it loses the specific friction modifiers, ahich can promote clutch pack or break band slipage. Im not anying everything anyone said is wrong, and i alone am right, that is far from true. I AM saying that not getting rid of contaminants in the oil is a bad idea, and its foolish to believe that its best left un touched. Automatic tranys are almost always neglected, and not thought of untill the vehicle wont move. Thats why a lotta ten second lube shops wound touch it, because they know that its most likly fucked by the time it rolls in. As far as job security, i agree, it is good. Point is, when a trany fails in a car, its a pain in the ass for the owner, and then it gets fixed. In my world, when somone i touch fails, its a bad day for everyone. and cam some times cost big paying customers. The point is, when somone comes in and drops 300 grand on somthing, we better make sure what we are doing when it comes to fixing it.

 

[Simple_serf]

Ranger5.0...

I wish the guys in the shop at my JD dealer thought that way. They always just try to sell us a new tractor everytime the old stuff breaks down and I am in for parts. Problem around here is that we used to be a small farm area. Now, we are lucky to break even. and forget the 300K machine, we are lucky to be able to run a used, very worn out 40 Year old machine.

My opinion on the trans...If it is in good shape, the flush, cleaning, etc won't hurt it. If it is screwed then you are going to notice stuff while the trans is rebuildable. If you let it go, when it finally does go BOOM you are going to be spending more $$$. I personally hate autos, but all of them in my family get serviced every 20K (axod anyone??). Even trannies that are considered Junk, like the axod, will give reasonable service life if they are maintained properly.

 

[Bent Bolt]

thats the difference between working on a 2000 trany, and a 15000 trany.

When it comes down to it, what differance does that make ?? Still $$. And BTW, I do repair F-550 with 50-70 grand worth of equipment on it. Those guys get antsy !!

.

With your therory of fresh atf lossening varnish, then its a bad idea to even change the ATF and filter? What hapens when the filter gets cloged by this "good grit" ? it starves the pump, then, trany death folows.

You are not reading my posts. Varnish happens when the ATF has been overheated due to hi temps. Such as from towing big trailers up big hills in summer. I have seen vehicles with 200k km's and no trans service and the trans and ATF looks great. Service it ?? You bet !!!

When trany fluid age's, it loses the specific friction modifiers, ahich can promote clutch pack or break band slipage. Im not anying everything anyone said is wrong, and i alone am right, that is far from true. I AM saying that not getting rid of contaminants in the oil is a bad idea, and its foolish to believe that its best left un touched. Automatic tranys are almost always neglected, and not thought of untill the vehicle wont move. Thats why a lotta ten second lube shops wound touch it, because they know that its most likly fucked by the time it rolls in.

I totally agree.!! 100%

As far as job security, i agree, it is good. Point is, when a trany fails in a car, its a pain in the ass for the owner, and then it gets fixed. In my world, when somone i touch fails, its a bad day for everyone. and cam some times cost big paying customers. The point is, when somone comes in and drops 300 grand on somthing, we better make sure what we are doing when it comes to fixing it.

We do the same thing, pulling wrenches. The $$ figures are different is all. I tried heavy duty for about 6 months back in the mid 90's. Hated it.

 

[Thumper113]

There is another reason why shops might not want to service a transmission with burnt fluid (which comes from a transmission that is ALREADY SLIPPING) or a lot of miles: People blame the shop for the subsequent failure, without realizing it would have failed anyway.

A transmission with burnt fluid HAS ALREADY failed. Why would you then expose yourself to claims when the owner tries to blame you for it?

BINGO!

I lost count on the number of times customers have come in requesting a transmission flush because they say their trans is acting strange. They seem to think that'll magically fix it. I pull the distick to find black smelly fluid. On some of 'em, I've dropped the transmission pan to show 'em the chunks of clutch debris & the piles of brass debris from worn out bushings. Only then do some of them realize a flush is a waste of money on their trans. So yeah, flushing an already worn out transmission can make the shop liable in the customers eyes (because they'll always say, "It was working fine before you flushed it")if things aren't explained properly before hand.

Same applies to installing a "shift kit" on a worn out or wearing out transmission. I've heard stories like, "That damn shift kit ruined my trans". when the fluid before the shift kit is dark & burnt. it even states in the directions, not to install unless the trans is in perfect operating condition.

On another note, I've flushed transmissions on 100k+ vehicles without issues. But, those are the owners that have serviced their transmissions & vehicle overall, on a regular basis. a flush on a high mileage transmission isn't gonna make it go south unless........something is already worn.

I flushed the trans on my 94 Bronco when it had 94,000 on it's original trans. last year at 172,000 miles the transmission took a dump. I doubt the flush at 94k had anything to do with that.

 

[blackwood87B2]

well I've had two automatics and i changed the fluid and filters on both and they died within 6,000 miles or so, i guess there's some truth to it

 

[thegoat4]

My grandmother had a severe blood clot in her femeral artery running all the way back to her heart. The hospital put her on some mild anticoagulants to slowly work the blood clot out. Sadly, a chunk came loose, went to her brain, and killed her.

Flushing a dirty transmission can cause a similar failure because ATF is a fairly aggressive cleaner, but you have to already have a severe sludge problem to pose any risk. If you check your trans fluid and it's just a little dark, or even a little burned, a flush won't be a problem. OTOH, if the fluid looks like hell, don't sweat it--just run it until it fails and put that flush money towards the overhaul.

That thing about "grit" helping the clutches grab is utter horseshit. If your ATF feels like lapping compound, your trans is hosed anyway and you can't blame an oil change for the inevitable failure.