Transmission Fluid?
rico46
05-20-2005, 08:25 AM
I have a question: I just bought a 95' GC Orvis with 127K on it. I have no idea when the trans fluid was last changed. I have heard that it is risky to have it changed at such a high mileage without knowing when it was last changed. My question is is this a myth, or is it true and I should just leave well enough alone?
SteveB05
05-20-2005, 09:00 AM
No myth. If the fluid is not a clear pink, then leave it alone. If it is a clear pink and it is operating properly, then you can give it a try.
ramairgto72
06-05-2005, 02:33 AM
I can tell you what to do, first off I worked at a Pens 10min oil change in Erie PA, lots of snow plow guys would have this done, and with good and bad happenings.
This is what happens when a trans gets high miles on it the clutch disks start to erode, like any stick trans but in a auto the clutching comes off and filters around with the fluid and some gets caught in the filter and thus causeing lower trans line pressure, this is a good and bad thing, if you keep driveing it you could see alot of miles before it dies, the bad thing is your trans is eating it's self to death, like Pizza the Hut.
When you do a T-tec or a total trans fulid change all the fluid is new and not choked and thick with clutch, what happens next is the line pressure gos back close to the stock figure, and even worse if you get your filter changed because you now working with clean unblocked pressure, this in turn will make you clutchings come together allmost like new, and then it happens the can't handle the new pressure and in turn eat themselfs and fall apart, then you have no clutch in your auto, it's all in the filter or the pan.
The best thing to do if your trans fluid looks ok and dose not smell like garlic is leave it alone, and if you still want to change it just do a trans pan drop and refill or step a little higher and go with a filter and pan refill, and I did on my AW4 on my 1993 JGC with 120.
This info was handed down to us when I worked at the Pen 10min oil change place by the company in 1995 we soon picked up the waver to have the people sign if the car had high miles on it.
I hope this helps you.
This is what happens when a trans gets high miles on it the clutch disks start to erode, like any stick trans but in a auto the clutching comes off and filters around with the fluid and some gets caught in the filter and thus causeing lower trans line pressure, this is a good and bad thing, if you keep driveing it you could see alot of miles before it dies, the bad thing is your trans is eating it's self to death, like Pizza the Hut.
When you do a T-tec or a total trans fulid change all the fluid is new and not choked and thick with clutch, what happens next is the line pressure gos back close to the stock figure, and even worse if you get your filter changed because you now working with clean unblocked pressure, this in turn will make you clutchings come together allmost like new, and then it happens the can't handle the new pressure and in turn eat themselfs and fall apart, then you have no clutch in your auto, it's all in the filter or the pan.
The best thing to do if your trans fluid looks ok and dose not smell like garlic is leave it alone, and if you still want to change it just do a trans pan drop and refill or step a little higher and go with a filter and pan refill, and I did on my AW4 on my 1993 JGC with 120.
This info was handed down to us when I worked at the Pen 10min oil change place by the company in 1995 we soon picked up the waver to have the people sign if the car had high miles on it.
I hope this helps you.
trannyman52
06-05-2005, 09:04 PM
ya gotta laugh!!!! Changing the fluid AND filter is a good thing,,,,gets wearing particles out of the system,,,,yes there can be problems if wear particles get trapped in the valve body when the service is done,,,,but if that's the case,,,,,where there's that much junk,,,,WELL,,,,.......Notice I said changing the fluid & filter,,,,,NOT a $$$$$$$flush!!!! P.S. clean the magnets in the pan!!!!!!!gooooood luck!!!!!!
ramairgto72
06-05-2005, 11:42 PM
ya gotta laugh!!!! Changing the fluid AND filter is a good thing,,,,gets wearing particles out of the system,,,,yes there can be problems if wear particles get trapped in the valve body when the service is done,,,,but if that's the case,,,,,where there's that much junk,,,,WELL,,,,.......Notice I said changing the fluid & filter,,,,,NOT a $$$$$$$flush!!!! P.S. clean the magnets in the pan!!!!!!!gooooood luck!!!!!!
I allways thought that the price of haveing a T Tec done was a little high, and the unit it's self does very little, see your trans pump pumps into one side of the unit pushing the new stuff in, so your trans is doing all the work. The only time you pluged in the unit is when you had to suck up trans fluid, like if you bought some B&M syn fluid in gallons, the unit could suck it up on the lower side of the piston. The in house trans fluid is in a compressed line that you would hook up to the unit and add the amount you needed.
If you have a trans thats somewhat new get the whole package done, the filter and T Tec and do it every time your dew for a trans fluid change, thats the big spenders way, but if you just changed the fluid a little sooner then factory recomended with a pan drain and a filter it would be just as good. For those who don't want to go under your 4x4 or whatever the T Tec and filter change at a place that does this like a (Jiffy Lube or Pens oil) is great and if they F things up you can get (in most cases) a comp.
I allways thought that the price of haveing a T Tec done was a little high, and the unit it's self does very little, see your trans pump pumps into one side of the unit pushing the new stuff in, so your trans is doing all the work. The only time you pluged in the unit is when you had to suck up trans fluid, like if you bought some B&M syn fluid in gallons, the unit could suck it up on the lower side of the piston. The in house trans fluid is in a compressed line that you would hook up to the unit and add the amount you needed.
If you have a trans thats somewhat new get the whole package done, the filter and T Tec and do it every time your dew for a trans fluid change, thats the big spenders way, but if you just changed the fluid a little sooner then factory recomended with a pan drain and a filter it would be just as good. For those who don't want to go under your 4x4 or whatever the T Tec and filter change at a place that does this like a (Jiffy Lube or Pens oil) is great and if they F things up you can get (in most cases) a comp.
SteveB05
06-06-2005, 01:40 AM
I have seen far too many transmissions buy the farm after getting thier first service @ 100,000 miles or more. I totally agree that services are good things (you wouldn't go 100,000 without an engine oil change) but the question is, if you don't know the service history...do you want to press your luck and possibly have a failure 3 blocks down the road, or just let the trans die a slower, unnatural death.
ramairgto72
06-06-2005, 02:18 AM
I know what your talking about, if you don't know what the history is how do you know what to do.
I know that my 1993 JGC had 120 on it and I had the filter and pan fluid rplaced on that AW4, and when I checked the fluid a day later I had "stuff" on the dip stick.... I talked to the guy as he was doing it and seen that he totaly cleaned that pan, sooooo i'm sure that something was kicked up or out or even something could have come off the clutch, however the 4x4 is still shifting fine, I know the AW4 is a good trans so I took the chance.
However if your going to think about doing it you have to be able to weigh some things.
1. The fluid looks clear and red. Do it? {Yes} I would T Tec with filter)
2. The fluid is dark but does not smell. Do it? {Maybe} a T Tec with filter, safe with filter and refill.
3. The fluid is dark and smells like garlic. Do it? {No}. But if the trans is not shifting correctly or is over heating chances are its going soon anyhow and a pan drop and refill is worth the chance of getting more life out of it.
I would go on these 3 basic steps and warrent them on what your future of the car/truck is going to be. You going to keep it or your passing it along to somebody else, or your driveing it into the ground.
I made the correct choice with the AW4 JGC however you also have to account that the person you got the car/truck (if you just got it) was going by #3.
It was a while ago, but when people would come to the Pens oil chang I worked at I would go by these 3 when I would check the Trans oil, I didnt screw people out of money and a trans, and I allways aired on not doing a T Tec but a trans filter and refill.
You also have to think about this, Military 6x6 and other HD Auto trans military rigs could go a very long time without a trans fluid change, I know they are built for this but still, I have seen a 1942 6x6 start up and drive after years and years of sitting. I do have a pic of it if you want to see it.
I know that my 1993 JGC had 120 on it and I had the filter and pan fluid rplaced on that AW4, and when I checked the fluid a day later I had "stuff" on the dip stick.... I talked to the guy as he was doing it and seen that he totaly cleaned that pan, sooooo i'm sure that something was kicked up or out or even something could have come off the clutch, however the 4x4 is still shifting fine, I know the AW4 is a good trans so I took the chance.
However if your going to think about doing it you have to be able to weigh some things.
1. The fluid looks clear and red. Do it? {Yes} I would T Tec with filter)
2. The fluid is dark but does not smell. Do it? {Maybe} a T Tec with filter, safe with filter and refill.
3. The fluid is dark and smells like garlic. Do it? {No}. But if the trans is not shifting correctly or is over heating chances are its going soon anyhow and a pan drop and refill is worth the chance of getting more life out of it.
I would go on these 3 basic steps and warrent them on what your future of the car/truck is going to be. You going to keep it or your passing it along to somebody else, or your driveing it into the ground.
I made the correct choice with the AW4 JGC however you also have to account that the person you got the car/truck (if you just got it) was going by #3.
It was a while ago, but when people would come to the Pens oil chang I worked at I would go by these 3 when I would check the Trans oil, I didnt screw people out of money and a trans, and I allways aired on not doing a T Tec but a trans filter and refill.
You also have to think about this, Military 6x6 and other HD Auto trans military rigs could go a very long time without a trans fluid change, I know they are built for this but still, I have seen a 1942 6x6 start up and drive after years and years of sitting. I do have a pic of it if you want to see it.
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