Difference between OEM and aftermarket ATF

[Kevin in Texas]

I am getting ready to have both of my cars ATF changed. 1993 Ford Explorer and 2001 Suburban. I have always taken my Ford to the same shop and they use Pennzoil. 1. Is there really any difference in ATF's that are made to each of the respective GM or Ford spec's? 2. Do any of the OEM's ATF have any extra ingredients in them that you don't find in aftermarket ATFs? I know that GM is supposed to have a special EP additive in their differential fluid that you don't find in Mobil 1 or other aftermarket diff fluids. 3. Is there any benefit to the new high milage ATF's like Maxlife, and others for my '93 Ford with 105K? So, Which ATF is better to use for my vehicles.

 

[Brad]

Make sure the fluid you are using meets the specs of the car maker. I don't know much about GM vehicles, but I know Ford requires ATF fluid to meet Mercon specs. There are different grades of fluid, Mercon, Mercon III, Mercon V. So, find out what grade your tranny uses and stick with it. Just make sure the fluid meets OEM specs and requirements and you should be O.K.

 

[VaderSS]

I don't think there is a big difference between OEM and other ATFs, but I go with the OEM.

 

[MolaKule]

Most fluids are to same specs. Unless you're towing, you can stick with the Dino fluids. "I know that GM is supposed to have a special EP additive in their differential fluid that you don't find in Mobil 1 or other aftermarket diff fluids." GM has a positraction additive for limited-slip differentials, but it's a friction modifier just for that purpose, comes in a 12 oz can I believe. On my '86 Burb, I use the a synthetic 75W140 in my diffy with NO GM posi additive. Why? My diffy contains an AUBURN unit that shears the heck out of the 75W90 fluid with the GM posi additive.

 

[OneQuartLow]

I really hope someone with broader experience on this topic chimes in. Synthetics ATF (M1, Amsoil, no doubt Schaeffers, et al) hold up better. If you tow this could be very beneficial. I recall a curve of fluid life of non-synth vs. synth ATF. The standard fluid went through the floor quickly as it heated which could lead to quick tranny failure & $ervice. The synthetic far outlasts the filter unless the vehicle catches on fire. Also, shift qualities improve, especially when cold. To me it makes at least as much sense to use synth ATF as it does synth motor oil. Beyond the disabling aspect and expensive service engines and transmissions share, transmissions see much longer service intervals, their condition is harder to monitor, failure goes from bad to stuck & without much warning. Contrast that with sludge buildup and reduced service life from using cheap dino motor oil. I have heard a couple reports of problems with the different friction characteristics of some synthetics in some transmissions. Choose on type compatibility, not just brand. YMMV. Any other positive experiences? David

 

[Johnny]

<b>Kevin:</b> The Pennzoil ATF that your shop uses is an exceptionally good ATF. It meets both GM DEXRON III and Mercon specs. It has one of the lowest pour points of any conventinal ATF and matches many synthetic ATF'S in pour point. As I have said on other post, Pennzoil ATF was the first ATF to stop the GM shudder problem, and GM is using this ATF as their benchmark for developing their next line of ATF. I guess they will call it DEXRON IV. There are other good ATF'S on the market but I really do not think you will go wrong by using the Pennzoil.

 

[Johnny]

Kevin: If you have a good sound transmission that you have taken care of, the answer would be no. It basically use the same pricipals as the HM oils. Maybe a litter higher VI to start with and some small amount of ester for seal conditioning.

 

[icruse]

[QUOTE]Originally posted by Johnny: [QB]Kevin: The Pennzoil ATF that your shop uses is an exceptionally good ATF. I can say by experience (just changed my ATF and put in the Pennzoil), wow, this is nice ATF. My 4 speed automatic 93 Grand Prix (3.1 v.6) with 226,000 miles is running nice and quiet and smooth with the most recent change in ATF. Pennzoil makes good products for a very good price and they are easy to locate and purchase (most everywhere you go you can find Pennzoil products). Good Day, Steven

 

[dickwells]

I bought an 88 GMC 305/.5ton/T400 that had 67K miles on it. I did a short change to Amsoil Trans fluid at that time. At about 110K miles I did a full flush with Amsoil. Truck now has 214 K on it with no problems and the tranny shifts much better than the 4L60E in my 02 Silverado. I was wanting to put Mobil 1 ATF in the Silvo but I see complaints of slippage from time to time so maybe I will grit my teeth and order some more Amsoil. Open to suggestions. RW

 

[widman]

I think Johnny basically covered most of it. A good Group II like Pennzoil or Chevron will be fine. Towing might push some to synthetic. Stay away from the cheapos, and don't think that you can modify the friction with additives to achieve what you should have. ATF+3 or +4 is very different from Dexron, and Mercon very different from Type F. From somewhere I pulled graph last week that showed the super high acid formation in Dexron II, much lower in Dexron III, Lower still in the "New Generation Dexron". As for high mileage, I have had very good results adding a seal conditioner to stop the leaks.

 

[Kevin in Texas]

quote:

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Originally posted by Johnny: Kevin: The Pennzoil ATF that your shop uses is an exceptionally good ATF. It meets both GM DEXRON III and Mercon specs. It has one of the lowest pour points of any conventinal ATF and matches many synthetic ATF'S in pour point. As I have said on other post, Pennzoil ATF was the first ATF to stop the GM shudder problem, and GM is using this ATF as their benchmark for developing their next line of ATF. I guess they will call it DEXRON IV. There are other good ATF'S on the market but I really do not think you will go wrong by using the Pennzoil.

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Thanks Johnny for the words of comfort about Pennzoil. As you well know, there is much debate over which engine oil to use and everybody knows that they need to change it regularily. However, not much is said about Tranny fluid and its need to be changed regularily. Until I started getting into oil, due to higher than normal oil consumption with my new '01 Burb, I thought all oil was the same. Now I know better! The difference in engine oils prompted to ask about the differences in ATF. Johnny, nobody answered this question. Is there any benefit to the new line of higher milage ATF's over standard ATF for a car with over 100K?