A friend has a Chevy full size with 100,000 on it. Has original Transmission fluid in it. He says he scared to change it do to the stories of changing out really old fluid with new stuff will mess up a transmission. I told him to change it. His transmission has a hesitation when he pulls off at times and will kinda slam home ... Whats yall verdict. WD
100,000 on Factory AFT . Safe to change out ??
- Thread starter WarDawg
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Change it. No question in my mind.
If the ATF is suspect and the thing shifts lousy, change the fluid.
Believe me - lots of people pass that "story" along. Changing fluid doesn't kill a transmission as fast as NOT changing the fluid.
Believe me - lots of people pass that "story" along. Changing fluid doesn't kill a transmission as fast as NOT changing the fluid.
Originally Posted By: Pablo
If the ATF is suspect and the thing shifts lousy, change the fluid.
Believe me - lots of people pass that "story" along. Changing fluid doesn't kill a transmission as fast as NOT changing the fluid.
Does that old story have a nugget of truth buried in it, or is it pure [censored]?
If the ATF is suspect and the thing shifts lousy, change the fluid.
Believe me - lots of people pass that "story" along. Changing fluid doesn't kill a transmission as fast as NOT changing the fluid.
Does that old story have a nugget of truth buried in it, or is it pure [censored]?
Do a pan drop change. Unbolt the pan, change the filter, and if the truck has a drain plug in the torque converter, change that too. Get as much fluid out as you can.
A home flush might be good in this case. Unhook the trans cooler lines, attach hoses, and have the trans suck in new fluid while dumping out the old.
I would not flush it with a machine that has its own pump. Flush machines that use the trans pump would be okay.
A home flush might be good in this case. Unhook the trans cooler lines, attach hoses, and have the trans suck in new fluid while dumping out the old.
I would not flush it with a machine that has its own pump. Flush machines that use the trans pump would be okay.
I vote for change it, but I would as suggested drop the pan change the filter and drain what you can. Then drain and refill every 30k after that. Because there has been a long time since the first cycle I'd think about doing it on a couple of 5k intervals. Flushing machines can be a risk. Many mechanics that do such tasks are not very careful and usually screw up the job. Figure out how to do the drain and refill yourself.
Install a drain plug in the T pan. Saves a mess the next time.
Originally Posted By: 01rangerxl
I would not flush it with a machine that has its own pump. Flush machines that use the trans pump would be okay.
All flush machines use some kind of pump to push new fluid into the pan of the AT. Although there are many types.
But the pump in the transmission is what always pushes the new fluid in the pan through the transmission.
Maybe you are talking about the flush machine that has a big cylinder with a plunger in the middle and old fluid goes on one side of the plunger and new fluid on the other side so as old fluid fills its side of the cylinder it pushes the piston and new fluid is pushed into the pan.
But other flush machines weigh the old fluid container and use a variable speed pump to push in new fluid only as fast as old fluid is coming out.
So both methods do a similar thing.
I would not flush it with a machine that has its own pump. Flush machines that use the trans pump would be okay.
All flush machines use some kind of pump to push new fluid into the pan of the AT. Although there are many types.
But the pump in the transmission is what always pushes the new fluid in the pan through the transmission.
Maybe you are talking about the flush machine that has a big cylinder with a plunger in the middle and old fluid goes on one side of the plunger and new fluid on the other side so as old fluid fills its side of the cylinder it pushes the piston and new fluid is pushed into the pan.
But other flush machines weigh the old fluid container and use a variable speed pump to push in new fluid only as fast as old fluid is coming out.
So both methods do a similar thing.
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It is safe to change it, that is a myth that people still push because of fear of being blamed for it.
Do a drain and fill by dropping the pan, then drive 10-15 miles, do another drain and fill. Repeat two more time, and replace any serviceable filter you have. From then on, do a drain and fill for the next 4 oil changes, and continue routine drain and fills every 15,000-20,000 miles or full flushes every 30,000 miles (longer with a synthetic ATF).
Do a drain and fill by dropping the pan, then drive 10-15 miles, do another drain and fill. Repeat two more time, and replace any serviceable filter you have. From then on, do a drain and fill for the next 4 oil changes, and continue routine drain and fills every 15,000-20,000 miles or full flushes every 30,000 miles (longer with a synthetic ATF).
I'd dump in a quart of Lucas no-slip in attempt to temporarily mask the damage and sell or trade it quick if it's slippin' and slammin' after 100k with no transmission service.
Or you can spend alot more time and money trying to nurse it back to health. But I'll bet it's days are numbered - low numbers.
Or you can spend alot more time and money trying to nurse it back to health. But I'll bet it's days are numbered - low numbers.
I agree with others that the condition of the transmission (pan, filter) need to be determined as a first step. Then after the pan is cleaned and filter is replaced, you can decide if you want to continue on with a flush or just do a few drain & refills.
If the pan and filter were really dirty and the fluid looked like driverway sealer, then you may need to consider replacing the filter a second time after a few weeks as the new fluid will be loosening up crud throughout the transmission.
You could also install a Magnefine filter and replace the element in a few weeks for the same reasons as mentioned above.
If the pan and filter were really dirty and the fluid looked like driverway sealer, then you may need to consider replacing the filter a second time after a few weeks as the new fluid will be loosening up crud throughout the transmission.
You could also install a Magnefine filter and replace the element in a few weeks for the same reasons as mentioned above.
Originally Posted By: XS650
Originally Posted By: Pablo
If the ATF is suspect and the thing shifts lousy, change the fluid.
Believe me - lots of people pass that "story" along. Changing fluid doesn't kill a transmission as fast as NOT changing the fluid.
Does that old story have a nugget of truth buried in it, or is it pure [censored]?
My version of the story is just junk I've read because I've never seen a transmission die after changing fluid, but every dead transmission I've seen has nasty, gross fluid. Well I take that back, I've seen some Honda transmissions full of metal and ATF looked OK, but we know the story there. (Honda defect)
Here goes the long story: Person has a transmission that shifts like garbage, slips, doesn't engage, bangs, etc really on it's last legs i.e damaged internally - maybe shot clutches, chewed gears. Fluid looks nasty. New fluid goes in, clean filter/screen/pan etc. Transmission dies two days later. Pretty darn sure the new fluid didn't "kill" the transmission, it was dead already and didn't know it.
Originally Posted By: Pablo
If the ATF is suspect and the thing shifts lousy, change the fluid.
Believe me - lots of people pass that "story" along. Changing fluid doesn't kill a transmission as fast as NOT changing the fluid.
Does that old story have a nugget of truth buried in it, or is it pure [censored]?
My version of the story is just junk I've read because I've never seen a transmission die after changing fluid, but every dead transmission I've seen has nasty, gross fluid. Well I take that back, I've seen some Honda transmissions full of metal and ATF looked OK, but we know the story there. (Honda defect)
Here goes the long story: Person has a transmission that shifts like garbage, slips, doesn't engage, bangs, etc really on it's last legs i.e damaged internally - maybe shot clutches, chewed gears. Fluid looks nasty. New fluid goes in, clean filter/screen/pan etc. Transmission dies two days later. Pretty darn sure the new fluid didn't "kill" the transmission, it was dead already and didn't know it.
Drain and Refill ATF and replace the OEM filter. Replace one of the quarts with TransX and run the ATF with TransX for a few months and drain and refill again with a OEM filter. Start to clean the varnish and sludge out of that transmission. The next ATF service should be performed in the same manner, however....run this batch 10K.
I believe that if an original transmission has been run on a mineral oil ATF for 100K, then the same type of ATF should be used....the frictions won't like another type of ATF oil. This is where I believe the transmissions going bad story originated and has been seen over and over again to be true. It's not a tale...it was just told wrong. Keep the same type of ATF that was run in the transmission.
I believe that if an original transmission has been run on a mineral oil ATF for 100K, then the same type of ATF should be used....the frictions won't like another type of ATF oil. This is where I believe the transmissions going bad story originated and has been seen over and over again to be true. It's not a tale...it was just told wrong. Keep the same type of ATF that was run in the transmission.
Originally Posted By: Alternator
I'd dump in a quart of Lucas no-slip in attempt to temporarily mask the damage and sell or trade it quick if it's slippin' and slammin' after 100k with no transmission service.
Or you can spend alot more time and money trying to nurse it back to health. But I'll bet it's days are numbered - low numbers.
Hmmmm...so your solution is mask the problem and dump it off on someone else? Just wondering how you'd feel if you were on the receiving end of that deal...
I'd dump in a quart of Lucas no-slip in attempt to temporarily mask the damage and sell or trade it quick if it's slippin' and slammin' after 100k with no transmission service.
Or you can spend alot more time and money trying to nurse it back to health. But I'll bet it's days are numbered - low numbers.
Hmmmm...so your solution is mask the problem and dump it off on someone else? Just wondering how you'd feel if you were on the receiving end of that deal...
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Originally Posted By: XS650
Originally Posted By: Pablo
If the ATF is suspect and the thing shifts lousy, change the fluid.
Believe me - lots of people pass that "story" along. Changing fluid doesn't kill a transmission as fast as NOT changing the fluid.
Does that old story have a nugget of truth buried in it, or is it pure [censored]?
The myth is started by some having some "issue" with their trans. It then dawns on them to service the trans. They do and it fails shortly there after due to the lack of maintenance (the cause of the "issue"). They blame the fluid change.
Originally Posted By: Pablo
If the ATF is suspect and the thing shifts lousy, change the fluid.
Believe me - lots of people pass that "story" along. Changing fluid doesn't kill a transmission as fast as NOT changing the fluid.
Does that old story have a nugget of truth buried in it, or is it pure [censored]?
The myth is started by some having some "issue" with their trans. It then dawns on them to service the trans. They do and it fails shortly there after due to the lack of maintenance (the cause of the "issue"). They blame the fluid change.
Originally Posted By: BullyT
Originally Posted By: Alternator
I'd dump in a quart of Lucas no-slip in attempt to temporarily mask the damage and sell or trade it quick if it's slippin' and slammin' after 100k with no transmission service.
Or you can spend alot more time and money trying to nurse it back to health. But I'll bet it's days are numbered - low numbers.
Hmmmm...so your solution is mask the problem and dump it off on someone else? Just wondering how you'd feel if you were on the receiving end of that deal...
I could see dumping it on a dealer as a trade in, but not a private sale.
Originally Posted By: Alternator
I'd dump in a quart of Lucas no-slip in attempt to temporarily mask the damage and sell or trade it quick if it's slippin' and slammin' after 100k with no transmission service.
Or you can spend alot more time and money trying to nurse it back to health. But I'll bet it's days are numbered - low numbers.
Hmmmm...so your solution is mask the problem and dump it off on someone else? Just wondering how you'd feel if you were on the receiving end of that deal...
I could see dumping it on a dealer as a trade in, but not a private sale.
A couple of months ago, I did a pan drop, filter change, and partial fluid replacement on my 2000 VW GTI 4-speed auto. This was at 103k miles on the OEM ATF.
I've put 5k miles on the VW since the fluid/filter change. Nothing but POSITIVE results. Improved shifting has been the most noticeable thing.
As long as there is nothing mechanically wrong with a transmission, a fluid/filter change at 100k+ miles won't hurt a thing.
I've put 5k miles on the VW since the fluid/filter change. Nothing but POSITIVE results. Improved shifting has been the most noticeable thing.
As long as there is nothing mechanically wrong with a transmission, a fluid/filter change at 100k+ miles won't hurt a thing.
How was it running before you did the service?
Originally Posted By: Alternator
How was it running before you did the service?
If you're asking me........It was OK, but the timing of some of the shifts was a little off. It would shift from 2nd to 3rd too soon, and on slight inclines, it would sometimes "hunt" for the right gear. FWIW, this happened when accellerating from a dead stop. I didn't notice any problems once at speed.
How was it running before you did the service?
If you're asking me........It was OK, but the timing of some of the shifts was a little off. It would shift from 2nd to 3rd too soon, and on slight inclines, it would sometimes "hunt" for the right gear. FWIW, this happened when accellerating from a dead stop. I didn't notice any problems once at speed.
There are alot of things that contribute to this myth.
1. 99% of drivers are not as "up" on this stuff as we are. Most have no clue of what maintainence needs done. Assumption is, "if its workin, I ain't messin(maintaining) with it.
2. Many mechanics WON'T touch a transmission. Those who will do anything, limit it to the flushes that don't change filters or take a look in the pan. Personally, even the great local shop I use will NOT drop the transmission pan....ever. Most they do is replace seals and remove and install units. They send all internal repairs out to a transmission shop.
3. Folks are more afraid of transmission shops than regular mechanics. Blame AAMCO(All Autos must come out) for this imo. Many fail to realize their issue might be something simple and cheap to fix(solenoid, harness connection, etc) and not a rebuild. I have talked to the guys down at the transmission shop I use and they tell me, "people wait till either the car ain't movin anymore or feels like it will blow apart".
As the guys at the shop say, people wait till its too late to fizx an issue and then say, "change the fluid, that will fix it right?....RIGHT?". Its like knowing you have a cavity in your tooth, waiting for a few months till its killing you, then complaining when you finally go to the dentist and he presents the expensive/ painful options.
1. 99% of drivers are not as "up" on this stuff as we are. Most have no clue of what maintainence needs done. Assumption is, "if its workin, I ain't messin(maintaining) with it.
2. Many mechanics WON'T touch a transmission. Those who will do anything, limit it to the flushes that don't change filters or take a look in the pan. Personally, even the great local shop I use will NOT drop the transmission pan....ever. Most they do is replace seals and remove and install units. They send all internal repairs out to a transmission shop.
3. Folks are more afraid of transmission shops than regular mechanics. Blame AAMCO(All Autos must come out) for this imo. Many fail to realize their issue might be something simple and cheap to fix(solenoid, harness connection, etc) and not a rebuild. I have talked to the guys down at the transmission shop I use and they tell me, "people wait till either the car ain't movin anymore or feels like it will blow apart".
As the guys at the shop say, people wait till its too late to fizx an issue and then say, "change the fluid, that will fix it right?....RIGHT?". Its like knowing you have a cavity in your tooth, waiting for a few months till its killing you, then complaining when you finally go to the dentist and he presents the expensive/ painful options.
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