synthetic ATF - any experience?
Thread Starter
Race Director
Joined: Aug 2000
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synthetic ATF - any experience?
anyone use these synthetic (automatic) transmission fluids - amsoil, royal purple, or redline? i'm guessing it probably doesn't make a lot of difference - i'm sure all three are quality products. looking for some comments on actual, real world, experience. TIA...
Team Owner
Joined: Sep 2001
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
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Tried Royal Purple, didn't find a noticeable difference in anything, and the previous fluid was still pretty good when it came out.
I'd think you'd need a temp gauge to see any difference, and/or dyno results showing less frictional losses.
I'd think you'd need a temp gauge to see any difference, and/or dyno results showing less frictional losses.
Le Mans Master
Joined: Apr 2000
Posts: 5,713
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From: Manassas VA
You didn't ask about Mobil, but that is what I use. My workvan is a better example then my vette, due to the vette gets driven very little.
My work van is a E350 diesel and weighs 9200 lbs all the time with what I carry. Well at 15,000 miles I had it flushed and mobil syn. installed. I change it regular and it now has 131,000 miles and runs great.
One other example I will give you is my wife's Honda pilot. Used Honda fluid for 100,000 and now that fluid is not available. It has been replaced with the Honda syn. fluid. Have 161,000 miles on it and it too, runs great.
My work van is a E350 diesel and weighs 9200 lbs all the time with what I carry. Well at 15,000 miles I had it flushed and mobil syn. installed. I change it regular and it now has 131,000 miles and runs great.
One other example I will give you is my wife's Honda pilot. Used Honda fluid for 100,000 and now that fluid is not available. It has been replaced with the Honda syn. fluid. Have 161,000 miles on it and it too, runs great.
Team Owner
Joined: Sep 2003
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Can't relate directly to your "first hand" BUT when I needed to do a service on a Dexron III car of my own and there's no DEXRON III any longer I looked at my choices and ruled out everything except this:
That is Dexron III spec done by Castrol for Allison and it's sold by two others also. The other choice would have been the Amsoil but I don't actually care for their "marketing" maneuvering. Most everything else is done to a Dexron VI spec and is it fine? Allison says not for a Dexron III spec usage. My car is Dexron III spec, I added a drain plug, did 8 quarts and a filter, 5K miles later drain and another fill with the same. I'd say it's likely quite close to a total TransSynd fill.
If you've a Dexron III spec transmission I believe there are choices. Are the synthetic the solution or a viable one. I'd think so but I chose the correct spec fluid.
One consideration and I believe a "must do" - DO NOT overfill or run an AT with any "over-fill" - it's a killer for sure, increased temps and on and on. If you've a reason to run an auxiliary cooler consider a thermostatic bypass for cooler temps. This isn't actually just a "truck thing"!
That is Dexron III spec done by Castrol for Allison and it's sold by two others also. The other choice would have been the Amsoil but I don't actually care for their "marketing" maneuvering. Most everything else is done to a Dexron VI spec and is it fine? Allison says not for a Dexron III spec usage. My car is Dexron III spec, I added a drain plug, did 8 quarts and a filter, 5K miles later drain and another fill with the same. I'd say it's likely quite close to a total TransSynd fill.
If you've a Dexron III spec transmission I believe there are choices. Are the synthetic the solution or a viable one. I'd think so but I chose the correct spec fluid.
One consideration and I believe a "must do" - DO NOT overfill or run an AT with any "over-fill" - it's a killer for sure, increased temps and on and on. If you've a reason to run an auxiliary cooler consider a thermostatic bypass for cooler temps. This isn't actually just a "truck thing"!
Last edited by WVZR-1; Nov 12, 2013 at 09:57 PM.
Team Owner
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The TranSynd is a deal at $10 per!
Race Director
Joined: Apr 2002
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From: Anaheim CA
I recall that leesvet posted about 6000 years ago on the C4 Corvettes Yahoo group that he read a test that was done on taxis in Atlanta. The transmissions went twice as long on synthetic fluid.
I was going to switch to synthetic but the shop that built my trans asked me to bring them 13 quarts of what I wanted in it. I decided at $10 a quart that I would go with regular ATF since my car is strictly a street car and only has 117,000 miles after 28 years so I don't drive it enough to need special ATF. I do drive this car every day, but everywhere I need to go is close by.
I was going to switch to synthetic but the shop that built my trans asked me to bring them 13 quarts of what I wanted in it. I decided at $10 a quart that I would go with regular ATF since my car is strictly a street car and only has 117,000 miles after 28 years so I don't drive it enough to need special ATF. I do drive this car every day, but everywhere I need to go is close by.
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Safety Car
Joined: Nov 2009
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From: Adelaide South Australia
I used Castrol Transmax Z at $14 a litre when I put the 3200 converter in (only using the radiator as a cooler), runs great and the internals of the trans have over 100,000 miles on it and i havent killed it yet !
Melting Slicks
Joined: Jul 2002
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From: Tallahassee fl
I have used Mobil 1 ATF in a couple cars and give it a thumbs up. I have even done half changes with it and experienced smoother shifting. I had one car, lincoln town car, that was shifting rough. I dropped the pan, changed the filter, and added in M1 ATF. never had a shifting problem again. Sold it at 175k miles with the original tranny in tact.
Race Director
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From: moraga ca
Your decision doesn't surprise me and I would have expected that. Rossler specs for fluid don't mention Amsoil by name but they do mention it's (synthetics) not a necessity. I've heard that some convertor manufacturers though don't recommend "synthetics" - just something I read on the "Internet"!
The TranSynd is a deal at $10 per!
The TranSynd is a deal at $10 per!
Instructor
Joined: Jul 2005
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I've read that newer conventional ATFs are actually worse than the old stuff. Newer ATFs don't need to stand up to as high a temperature with the advent of torque converter clutches which cut down on slippage and thus heat. With newer ATFs being less resilient to high temps, synthetic ATF is always a good idea.
Max G’s
Joined: Nov 2008
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From: Monroe OH
NCM Sinkhole Donor
I like the idea of synthetic fluid myself and would probably use it if I hadn't been told to run conventional in my Stage 4 4l60. Don't know why the builder did not want me to use synthetic, but I am going to use what he suggest. And I have recently experienced the same thing with the new engine I had built. The builder only wants 20/50 conventional racing oil ran in it. I didn't question it and since I change the oils frequently, I guess the conventional will do.
I will add that for my daily drivers I only use synthetic in the engines and the recommended trans fluid type.
I will add that for my daily drivers I only use synthetic in the engines and the recommended trans fluid type.
Safety Car
Joined: Nov 2009
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From: Adelaide South Australia
[QUOTE=l98tpi;1585424058]I like the idea of synthetic fluid myself and would probably use it if I hadn't been told to run conventional in my Stage 4 4l60. Don't know why the builder did not want me to use synthetic, but I am going to use what he suggest. And I have recently experienced the same thing with the new engine I had built. The builder only wants 20/50 conventional racing oil ran in it. I didn't question it and since I change the oils frequently, I guess the conventional will do.[QUOTE]
he probably doesnt want any of those darn new fangled fancy oils in there messing stuff up, its the work of the devil you know !
he probably doesnt want any of those darn new fangled fancy oils in there messing stuff up, its the work of the devil you know !