So then which fluid is the best? dexron 6, redline or Amsoil?
Transmission life. How to get the best?
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You've asked this question a gizillion times.quote:
Originally posted by stingray427:
So then which fluid is the best? dexron 6, redline or Amsoil?
Use Dexron-VI when you have the flush done at the dealership. It may not be as good as RL or Amsoil on paper, but it will perform just as well if not better when it comes to low-temp/fuel economy. Thought it isn't that big of an issue, using Dexron-VI will eliminate any warranty concerns that you may have with unlicensed fluids, which may be a concern with you.
Oh, and here's a little info for you on the improvements of Dexron-VI over Dexron-III(H):
Anyone have a non-GM product to try the Dexron VI in????
I already have a case of ATF+4 fluid for a Ford. Just waiting for the filter & cooler before doing the flush.
Bulwnkl, if you read the GM Dexron-6 info above, you'll see that a simple fluid SPEC can greatly improve the life of the transmission or at least the clutch wear by 120%.
Glad that I've been using Mobil1/Amsoil/Redline ATF's for 20 years. Can't wait until these boutique companies come out with group 4&5 light ATFs.
And concerning cold weather, the Amsoil, Mobil1, Redline..and some of the synth blends, even though they are thicker(7.2 vs 6.0) at 212F,they actually have better cP-40 numbers. To me, this means that Dexron-VI might not be all that they hype it up as. Sorry, but the cold specs are similar to MerconV. Nothing there to brag about. Seems that Dexron-VI, even though thin at 212F, thickens quicker as the temperature drops(maybe not as much group III as we hope).
If you really want improved MPG, then the ATF needs to be easiest flowing at all temps and not just 100c.
I already have a case of ATF+4 fluid for a Ford. Just waiting for the filter & cooler before doing the flush.
Bulwnkl, if you read the GM Dexron-6 info above, you'll see that a simple fluid SPEC can greatly improve the life of the transmission or at least the clutch wear by 120%.
Glad that I've been using Mobil1/Amsoil/Redline ATF's for 20 years. Can't wait until these boutique companies come out with group 4&5 light ATFs.
And concerning cold weather, the Amsoil, Mobil1, Redline..and some of the synth blends, even though they are thicker(7.2 vs 6.0) at 212F,they actually have better cP-40 numbers. To me, this means that Dexron-VI might not be all that they hype it up as. Sorry, but the cold specs are similar to MerconV. Nothing there to brag about. Seems that Dexron-VI, even though thin at 212F, thickens quicker as the temperature drops(maybe not as much group III as we hope).
If you really want improved MPG, then the ATF needs to be easiest flowing at all temps and not just 100c.
Kestas
Staff member
It takes more than viscosity numbers to match up two transmission fluids. There's also friction characteristics to consider.
I've been tempted to use Dexron-VI in my Ford vehicles because we got a pail of it for free at work, and because of the Dexron/Mercon overlap with most products on the shelf. But I don't have any assurance that Dexron-VI is appropriate for Mercon applications, so I left it alone. I think my colleague put it in his 90 Bronco.
I've been tempted to use Dexron-VI in my Ford vehicles because we got a pail of it for free at work, and because of the Dexron/Mercon overlap with most products on the shelf. But I don't have any assurance that Dexron-VI is appropriate for Mercon applications, so I left it alone. I think my colleague put it in his 90 Bronco.
I believe that Molakule has said this before, but the main difference between Pennzoil Mineral and Mobil 1 synthetic automatic transmission fluid will be the basestock, and not the additive package. The two fluids will still use similar additive packages but the quality of the base oil will be much better with the M1 product, evidently. This is one reason why using a synthetic fluid does not automatically guarantee the ability to extend fluid changes beyond the recommended interval; the base oil may be able to handle it, but the additive package may not.
You've yet to show me evidence that synthetic ATFs don't shear. I recall a transmission UOA from Al w/M1 ATF and sheared just as much as a conventional fluid of the same type. The newer Dexron-VI/Mercon SP fluids will retain their viscosity very well and shear no where as much as their Dexron-III(H) counterparts, synthetic or dino, which is why Dexron-VI's shear stability has improved by a huge amount.
PS- No offense meant, but I really do not think you (or I, or most on this board) understand the chemical differences between these various ATF specifications, especially the make-up of the friction modifiers. For that reason alone, you should not use ATF+4 in a Ford as there may be long-term durability issues with clutch wear due to additive incompatibility.
I haven't seen any UOAs that show that SP or DexVI don't shear. All I see is GM technobabble.
All ATFs shear, some more than others.
Visit the UOA section. There are several where the synthetics didn't shear. Sure, there might be some that sheared, but besides fluid quality, driving style and transmission type make a huge difference in whether a fluid will shear or not. There are no sample sizes of M1 shearing consistently.
All ATFs shear, some more than others.
Visit the UOA section. There are several where the synthetics didn't shear. Sure, there might be some that sheared, but besides fluid quality, driving style and transmission type make a huge difference in whether a fluid will shear or not. There are no sample sizes of M1 shearing consistently.
Here's one for Mercon-SP, note the minimal viscosity change:
http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=3;t=001053
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=50;t=000049
http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=3;t=001053
Yeah it sheared. 10% is a lot. And, that SP was only used for 20k(and was it even worked hard) miles and not 50k or 100k or a lifetime. The thought of that SP fluid hitting 4.0cst by 100k is pretty scary. And, if the new ATF spec for Mercon SP is 5.5-6.0, then that UOA showed it sheared OUT OF SPEC at 5.4! I expect DexronVI to be just as pathetic! Nothing but mild updates to previous specs, no leaps and bounds there!
The Sentra isn't a viable comparison. Full flushes weren't performed. Jatco boxes will roast ANY fluid. Comparing two different vehicles doesn't count. A Jatco can make an Allison look underworked! Plus, there isn't a large enough sample. Flush that Sentra with Dexron VI and then see how poorly it performs.
Lets see the Dexron VI UOAs proving that it is a viable 30k, 60k, or 100k and not silly bench testing?
Or, should we just wait 3 years when Aamco/Cottman stock prices go up because of the unlimited supply of failed transmissions needing out of warranty rebuilds, because their owners read the owners' manual and didn't bother with simple ATF maintenance.
Blind faith with OEM specs and recommendations seems to cause every failure whether cooling, oil or ATF related!
Used Amsoil still at 7.0:
only 8.8k on this Nissan:
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=50;t=000069
51k on the Amsoil here:
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=50;t=000055
Lifetime fill garbage(VW uses pretty decent fluids):
http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=50;t=000045
Sheared typical factory fill:
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=50;t=000056
Even MerconV(one the earlier high end OEM ATFs) doesn't hold up too well:
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=50;t=000022
Notice that the lifetime VW fill has issues.
Notice that the best UOA is with Amsoil ATF AND a 6ish micron filter.
Does GM include micron filtration in their transmission??
This is a thread on 'best transmission life' and not about fluids, their shearing ability, or other taurian emissions.
Aftermarket cooling should be considered mandatory. An ATF temp gauge will allow you to pick the correct size(or just use a thermostat).
Aftermarket filtering should be a must. ALL ATF UOAs show excessive wear to the point that some seem to think that it is acceptable.
Upgraded fluids should be considered, especially if the OEM stuff is overly priced or a poor performer.
Regular ATF change intervals need to be performed to refresh the fluids viscosity, to remove any wear(abrasives) in the fluid, and to refresh the additive package.....
And, besides the above, a UOA will give you an idea how well YOUR driving style and how well YOUR transmission is holding up to the fluid you use, regardless of brand chosen!
The Sentra isn't a viable comparison. Full flushes weren't performed. Jatco boxes will roast ANY fluid. Comparing two different vehicles doesn't count. A Jatco can make an Allison look underworked! Plus, there isn't a large enough sample. Flush that Sentra with Dexron VI and then see how poorly it performs.
Lets see the Dexron VI UOAs proving that it is a viable 30k, 60k, or 100k and not silly bench testing?
Or, should we just wait 3 years when Aamco/Cottman stock prices go up because of the unlimited supply of failed transmissions needing out of warranty rebuilds, because their owners read the owners' manual and didn't bother with simple ATF maintenance.
Blind faith with OEM specs and recommendations seems to cause every failure whether cooling, oil or ATF related!
Used Amsoil still at 7.0:
only 8.8k on this Nissan:
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=50;t=000069
51k on the Amsoil here:
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=50;t=000055
Lifetime fill garbage(VW uses pretty decent fluids):
http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=50;t=000045
Sheared typical factory fill:
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=50;t=000056
Even MerconV(one the earlier high end OEM ATFs) doesn't hold up too well:
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=50;t=000022
Notice that the lifetime VW fill has issues.
Notice that the best UOA is with Amsoil ATF AND a 6ish micron filter.
Does GM include micron filtration in their transmission??
This is a thread on 'best transmission life' and not about fluids, their shearing ability, or other taurian emissions.
Aftermarket cooling should be considered mandatory. An ATF temp gauge will allow you to pick the correct size(or just use a thermostat).
Aftermarket filtering should be a must. ALL ATF UOAs show excessive wear to the point that some seem to think that it is acceptable.
Upgraded fluids should be considered, especially if the OEM stuff is overly priced or a poor performer.
Regular ATF change intervals need to be performed to refresh the fluids viscosity, to remove any wear(abrasives) in the fluid, and to refresh the additive package.....
And, besides the above, a UOA will give you an idea how well YOUR driving style and how well YOUR transmission is holding up to the fluid you use, regardless of brand chosen!
I think getting the correct/best ATF for your particular trans, and keeping up with flushes/pan drops is the key.
in my specfic case:
got car with 4R70w with 72k mies. Had the typical shudder during 3-4(od) shift. got flushed with Merc-V, 99% of the shudder went away at once after the flush.
kept up with Merc-V flushes every 25k miles or so, and a pan drop (so the filter also gets changed) every 3rd flush. shudder has never returned, and shifts are smooth. VERY seldom, when it's very cold outside I notice a "hesitant" 3-4 shift, but after the ATF warms up, it goes away, always.
Also, because I know that the sensitive spot is the 3-OD shift, whenever I know I'm not going to drive above 40 mph or so, or when I think short, slow trip can cause a lot of 3-OD, and OD-3 shifts (back and forth), I turn off the OD and "save" or avoid unnecessary 3-OD shifts as much as I can.
This caution coupled with above mentioned flushes has kept the 4R70w in my Tbird in almost flawless condition: right now at 113k miles. I know that's not a lot miles, but for a trans that has a bad reputation, I think it's pretty ok. several people I know have had repairs/rebuilds at this mileage...I hope I can keep it up.
I don't have any coolers addaed or temp gauges, not because I think they're not needed, but I can't afford it. my ATF looks red/pink always.
the only additive I used (once) was Lubeguard Red with my 2nd Merc-V flush...difficult to evaluate if it did anything. I never used it again (for no particular reason)
[ July 21, 2006, 11:00 AM: Message edited by: 97tbird ]
in my specfic case:
got car with 4R70w with 72k mies. Had the typical shudder during 3-4(od) shift. got flushed with Merc-V, 99% of the shudder went away at once after the flush.
kept up with Merc-V flushes every 25k miles or so, and a pan drop (so the filter also gets changed) every 3rd flush. shudder has never returned, and shifts are smooth. VERY seldom, when it's very cold outside I notice a "hesitant" 3-4 shift, but after the ATF warms up, it goes away, always.
Also, because I know that the sensitive spot is the 3-OD shift, whenever I know I'm not going to drive above 40 mph or so, or when I think short, slow trip can cause a lot of 3-OD, and OD-3 shifts (back and forth), I turn off the OD and "save" or avoid unnecessary 3-OD shifts as much as I can.
This caution coupled with above mentioned flushes has kept the 4R70w in my Tbird in almost flawless condition: right now at 113k miles. I know that's not a lot miles, but for a trans that has a bad reputation, I think it's pretty ok. several people I know have had repairs/rebuilds at this mileage...I hope I can keep it up.
I don't have any coolers addaed or temp gauges, not because I think they're not needed, but I can't afford it. my ATF looks red/pink always.
the only additive I used (once) was Lubeguard Red with my 2nd Merc-V flush...difficult to evaluate if it did anything. I never used it again (for no particular reason)
[ July 21, 2006, 11:00 AM: Message edited by: 97tbird ]
Why not just get it powerflushed and remove all fluid at one time and put in new trans fluid, Amsoil or Dexron 6?quote:
Originally posted by The Critic:
unDummy,
Since when did fluids shear continuously without stopping ?? Fluids will shear THEN thicken up due to oxidation, so it won't shear non stop and lose 4.0cst by 100K.
There was a recent sample of Dexron-III (G or H revision) posted on a Jeep AW box. Fluid sheared more on a percentage basis compared to Mercon SP.
And if you had taken a sample of the Amsoil ATF on the Tundra at 20K, would it still be at 6.3+ cst??? Could it have been at 5.5 cst??? You can't answer that question.
As for Al's transmission, he had drained and refilled the unit five times with Mobil 1 ATF. Go back and reread the thread. If draining and refilling the unit five times with Mobil 1 ATF isn't equivalent to a full flush, I do not know what is.
unDummy,
Since when did fluids shear continuously without stopping ?? Fluids will shear THEN thicken up due to oxidation, so it won't shear non stop and lose 4.0cst by 100K.
There was a recent sample of Dexron-III (G or H revision) posted on a Jeep AW box. Fluid sheared more on a percentage basis compared to Mercon SP.
And if you had taken a sample of the Amsoil ATF on the Tundra at 20K, would it still be at 6.3+ cst??? Could it have been at 5.5 cst??? You can't answer that question.
As for Al's transmission, he had drained and refilled the unit five times with Mobil 1 ATF. Go back and reread the thread. If draining and refilling the unit five times with Mobil 1 ATF isn't equivalent to a full flush, I do not know what is.
Since when did fluids shear continuously without stopping ?? Fluids will shear THEN thicken up due to oxidation, so it won't shear non stop and lose 4.0cst by 100K.
There was a recent sample of Dexron-III (G or H revision) posted on a Jeep AW box. Fluid sheared more on a percentage basis compared to Mercon SP.
And if you had taken a sample of the Amsoil ATF on the Tundra at 20K, would it still be at 6.3+ cst??? Could it have been at 5.5 cst??? You can't answer that question.
As for Al's transmission, he had drained and refilled the unit five times with Mobil 1 ATF. Go back and reread the thread. If draining and refilling the unit five times with Mobil 1 ATF isn't equivalent to a full flush, I do not know what is.
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