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Old Sep 11, 2007 | 02:52 PM
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Trans fluid

I'm planning on changing out the trans fluid on my diesel in a couple of weeks.
Last change was when I bought the truck in 2005 in which I changed out the filter as well. I don't plan on changing the filter this time around. The truck has 184,216 miles. No trans work has ever been completed other than the fluid change at 160,000. Other than Mercon, any suggestions in fluid type?
Synthetic or conventional?
Jeff
 
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Old Sep 11, 2007 | 04:05 PM
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I was told by BTS not to use synth. in our trannys. He said its to slick. so i stick with mercon. change it at recommend times.
 
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Old Sep 11, 2007 | 09:17 PM
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Are you using the new Mercon V, or do you still have access to the Dexron III?
 
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Old Sep 11, 2007 | 09:26 PM
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I'm not sure what I'm currently using. I kept no records.
 
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Old Sep 11, 2007 | 09:50 PM
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You could always use the fluid that BTS uses in their transmissions, which is Schaeffer's All Trans Supreme. According to the Schaeffer's website, it's for use in transmissions speced for Dex III, Merc, and Merc V, so you wouldn't have to worry about the particular spec. It looks to fare pretty well in Ford's Aluminum Oxidation test as well. http://www.schaefferoil.com/204_transmission_fluid.html
 
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Old Sep 11, 2007 | 10:10 PM
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Why is synthetic too slick to use in a 4R100?
 
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Old Sep 11, 2007 | 10:13 PM
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Two reasons. One, some believe that the fluid is too slick, and will cause the clutch plates in the trans to slip. Two, the thought is the full synthetics don't do as good of a job of holding and utilizing critical additives put in the fluid.
 
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Old Sep 11, 2007 | 10:44 PM
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So. If the clutch plates are slipping, what would the symptoms be?
 
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Old Sep 12, 2007 | 07:46 AM
  #9  
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Thanks for the input JT....There is a dealer about 7 miles from my place. I'll check it out.
Jeff
 
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Old Sep 12, 2007 | 07:48 AM
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Originally Posted by Rick2001
Why is synthetic too slick to use in a 4R100?
It isn't. Anyone that says it is doesn't understand the MERCON rating system.

Ford licenses companys to make MERCON V (no more MERCON) fluids. To get that license the company has to submit samples to Ford for testing. One of the many tests determines how slippery the fluid is. If it is too slippery or not slippery enough Ford won't license that fluid as MERCON V.

So the old wive's tale that synthetic is too slippery is a myth. I'm surpised the Brian still believes it.
 
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Old Sep 12, 2007 | 07:49 AM
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Where can one get Schaeffers Tranny fluid ? Auto Zone, Wally World, or where ? Or do you have to order it ?
 
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Old Sep 12, 2007 | 07:49 AM
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Originally Posted by Rick2001
So. If the clutch plates are slipping, what would the symptoms be?
The fluid turns black in a mile or two, and in another mile or two you're walking.
 
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Old Sep 12, 2007 | 08:00 AM
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Well I have out about 30,000 miles on a replacement transmission. The truck us usually pulling something behind it from 6500 to 12,000 lbs. It is a ' built ' tranny from Power Deman. Has all the good parts like BTS etc.

I have been running Royal Purple since day one. NEVER SLIPPS..

I have changed the fluid once and it was just like new.
 
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Old Sep 12, 2007 | 08:06 AM
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If you read that Shaeffer's spec sheet, that All Trans Supreme is partially synthetic.
Part of it's base stocks are PAO based.

Also, for me, it's hard to find.
 
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Old Sep 12, 2007 | 08:13 AM
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If you go to the schaffer's website, they have a dealer locator, type in your zip and the closest dealer pops up, Kwikk there should be one in the Seattle area. There's one in Spokane Valley, Moses Lake and CDA, ID.
 
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