What would be the most important limit in changeing out a ATF like the new Dex 6? Vis, TAN, solids or wear metals or something else?
bruce
bruce
What is the fluid condeming loimts for Dex 6
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I would say wear metals and acids but that has no basis on anything.
Originally Posted By: bruce381
What would be the most important limit in changeing out a ATF like the new Dex 6? Vis, TAN, solids or wear metals or something else?
bruce
The most important limit? You're a few gross profit dollars short for the day, and someone comes in with dark Dex 6 in their trans... one flush later, problem solved!
What would be the most important limit in changeing out a ATF like the new Dex 6? Vis, TAN, solids or wear metals or something else?
bruce
The most important limit? You're a few gross profit dollars short for the day, and someone comes in with dark Dex 6 in their trans... one flush later, problem solved!
Originally Posted By: Big O Dave
Originally Posted By: bruce381
What would be the most important limit in changeing out a ATF like the new Dex 6? Vis, TAN, solids or wear metals or something else?
bruce
The most important limit? You're a few gross profit dollars short for the day, and someone comes in with dark Dex 6 in their trans... one flush later, problem solved!
Originally Posted By: bruce381
What would be the most important limit in changeing out a ATF like the new Dex 6? Vis, TAN, solids or wear metals or something else?
bruce
The most important limit? You're a few gross profit dollars short for the day, and someone comes in with dark Dex 6 in their trans... one flush later, problem solved!
The truth is always the best laughter.
Originally Posted By: Big O Dave
Originally Posted By: bruce381
What would be the most important limit in changeing out a ATF like the new Dex 6? Vis, TAN, solids or wear metals or something else?
bruce
The most important limit? You're a few gross profit dollars short for the day, and someone comes in with dark Dex 6 in their trans... one flush later, problem solved!
LOL
Originally Posted By: bruce381
What would be the most important limit in changeing out a ATF like the new Dex 6? Vis, TAN, solids or wear metals or something else?
bruce
The most important limit? You're a few gross profit dollars short for the day, and someone comes in with dark Dex 6 in their trans... one flush later, problem solved!
LOL
Depends on transmission. Combination of all is something to look at.
I know that certain transmission manufacturers use time, mileage, TAN, total wear PPM, viscosity lost,..... if any "one" exceeds a given spec, flush away.
Automakers tend to be pretty weak since mileage and visual condition are their typical parameters. Mileage is meaningless and the 'visual' debate goes on forever.
Industrial and higher end units will have requirements concerning 'all of the above' specs.
I know that certain transmission manufacturers use time, mileage, TAN, total wear PPM, viscosity lost,..... if any "one" exceeds a given spec, flush away.
Automakers tend to be pretty weak since mileage and visual condition are their typical parameters. Mileage is meaningless and the 'visual' debate goes on forever.
Industrial and higher end units will have requirements concerning 'all of the above' specs.
Originally Posted By: Whitewolf
TAN, metals and shear. Having said that the DEXRON-VI fluids are very shear stable so if you see a used oil analysis showing less than KV 100C of about 5.3cSt then you need to look for some kind of contamination.
A little more needed whitwolf how high a TAN and metals till damage or change in "feel". Sorry had to ask.
bruce
TAN, metals and shear. Having said that the DEXRON-VI fluids are very shear stable so if you see a used oil analysis showing less than KV 100C of about 5.3cSt then you need to look for some kind of contamination.
A little more needed whitwolf how high a TAN and metals till damage or change in "feel". Sorry had to ask.
bruce
""Change in 'feel' is a tough""
Ok shudder then, does TAN increase or vis drop or wear metals
indicate increased likleyhood of shudder? or a change in "feel"
bruce
Ok shudder then, does TAN increase or vis drop or wear metals
indicate increased likleyhood of shudder? or a change in "feel"
bruce
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Not really. Those changes are more like the things that we used to see when base oils were not as good as they are now. That is why it's best to stick to the owners manual because the OEMs have tested the fluids both to and beyond the limit. You can't easily see that by chemical analysis.
Whitewolf, I guess now days with the new, improved base stocks we can follow the OEM guidelines, but in the "bad" old days, that wasn't always the case.
As an owner of a shop, should we strictly adhere to the OEM guidelines in every case, or is there some reliable way we can tell when the ATF should be changed in severe service conditions?
Today, one of my fleet accounts brought in two cars that they are getting ready to retire from the fleet and sell. Their philosophy is to get the car in as good a condition as is possible before selling it, and they asked us to inspect both vehicles, and as a matter of course, change the ATF. One was an '03 Sentra with 50K miles on it, and the other was an '04 Corolla, also with 50K miles. The Sentra uses Nissan-Matic D fluid and the Corolla uses T-IV.
Both had dark ATF, and one (I can't remember which now) had a notice on the ATF dipstick that indicated that the ATF should never need changing under "normal" circumstances. We told the fleet administrator that the color of the fluid is not a reliable indicator of the need for a fluid change, but he insisted on changing the fluid in both vehicles.
These cars are driven pretty hard by youngsters (LDS missionaries) so I don't think that their circumstances were "normal."
Please enlighten me!
As an owner of a shop, should we strictly adhere to the OEM guidelines in every case, or is there some reliable way we can tell when the ATF should be changed in severe service conditions?
Today, one of my fleet accounts brought in two cars that they are getting ready to retire from the fleet and sell. Their philosophy is to get the car in as good a condition as is possible before selling it, and they asked us to inspect both vehicles, and as a matter of course, change the ATF. One was an '03 Sentra with 50K miles on it, and the other was an '04 Corolla, also with 50K miles. The Sentra uses Nissan-Matic D fluid and the Corolla uses T-IV.
Both had dark ATF, and one (I can't remember which now) had a notice on the ATF dipstick that indicated that the ATF should never need changing under "normal" circumstances. We told the fleet administrator that the color of the fluid is not a reliable indicator of the need for a fluid change, but he insisted on changing the fluid in both vehicles.
These cars are driven pretty hard by youngsters (LDS missionaries) so I don't think that their circumstances were "normal."
Please enlighten me!
the dark colored friction material in import auto transmissions has bought many an Iffy Lube owner a new Monarch lux. bux. motor home
Originally Posted By: Whitewolf
The imports are not alone. Some OEMs use carbon fiber and that can discolor the fluid quite quickly.
Good info.
The imports are not alone. Some OEMs use carbon fiber and that can discolor the fluid quite quickly.
Good info.
So, is there some reliable way we can tell when the ATF should be changed in severe service conditions?
Originally Posted By: Big O Dave
So, is there some reliable way we can tell when the ATF should be changed in severe service conditions?
OEMs usually give a recommendation for severe service and normal service.
Toyota for example, states that the fluid should not need to be replaced for the life of the unit under most operating conditions. However, under the scheduled maintenance guide, it does state that if the vehicle is used for towing, a change every 60k miles is required.
In addition, OEMs usually have published instructions when it comes to fluid inspection. When Toyota had a Scion FAQ up on their site a few years ago, the site stated that if the transmission fluid became discolored, showed any sediment, or had a burned odor, it should be replaced immediately. It also stated that under many service conditions, the fluid could last at least 60,000 miles.
Hyundai, Chrysler and Honda have also released info regarding fluid condition. Honda said in a TSB for transmission repair that even if the fluid smells awful or is very dark, it is normal. Chrysler and Hyundai both state (actually Chrysler says this right in the owners manual) that the fluid will discolor and it does not mean that a fluid change is required.
My best advice is to just follow the OEM service recommendations. Sometimes, some units simply do not require a fluid change even under severe service, so keep that in mind as well.
So, is there some reliable way we can tell when the ATF should be changed in severe service conditions?
OEMs usually give a recommendation for severe service and normal service.
Toyota for example, states that the fluid should not need to be replaced for the life of the unit under most operating conditions. However, under the scheduled maintenance guide, it does state that if the vehicle is used for towing, a change every 60k miles is required.
In addition, OEMs usually have published instructions when it comes to fluid inspection. When Toyota had a Scion FAQ up on their site a few years ago, the site stated that if the transmission fluid became discolored, showed any sediment, or had a burned odor, it should be replaced immediately. It also stated that under many service conditions, the fluid could last at least 60,000 miles.
Hyundai, Chrysler and Honda have also released info regarding fluid condition. Honda said in a TSB for transmission repair that even if the fluid smells awful or is very dark, it is normal. Chrysler and Hyundai both state (actually Chrysler says this right in the owners manual) that the fluid will discolor and it does not mean that a fluid change is required.
My best advice is to just follow the OEM service recommendations. Sometimes, some units simply do not require a fluid change even under severe service, so keep that in mind as well.
Originally Posted By: The Critic
Originally Posted By: Big O Dave
Originally Posted By: bruce381
What would be the most important limit in changeing out a ATF like the new Dex 6? Vis, TAN, solids or wear metals or something else?
bruce
The most important limit? You're a few gross profit dollars short for the day, and someone comes in with dark Dex 6 in their trans... one flush later, problem solved!
You guys are brutal.....funny but brutal
Originally Posted By: Big O Dave
Originally Posted By: bruce381
What would be the most important limit in changeing out a ATF like the new Dex 6? Vis, TAN, solids or wear metals or something else?
bruce
The most important limit? You're a few gross profit dollars short for the day, and someone comes in with dark Dex 6 in their trans... one flush later, problem solved!
You guys are brutal.....funny but brutal
My rule of thumb for the GM4l60 & 80 series is 30,000 miles. Lots of people argue with me that 30k is way too often but every one I have done that with has gone well over 200k with no rebuild under lots of city driving which I consider severe. The owners manual in my 06 GMC says 50k severe & 100k normal use. However, I'm sticking with my 30k because the cost is minimal if I do it myself. Note, I only drop the pan & replace the filter every other change and may go to every 3rd change because the only real "dirty" filter is always the first one.
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