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Transmission Cooler Return Line

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Old Nov 1, 2005 | 10:38 AM
  #1  
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Transmission Cooler Return Line

Quick question for ya.

I'm about to do my 30000 mile maintenance and will flush my tranny utilizing the Transmission Fluid Return line. I noticed there was nothing related to this in the tech folder. I did however find a step by step procedure online.

My questions are as follows:

1. Do you disconnect the Return line at the rear of the tranny (hard line) or at the cooler?
2. Does anyone have a pic of the return line on a 6.0 PSD ( I just want to make absolutely sure I have the right one ).
3. I have heard two schools of thought when using this method:

a. After draining and filling the pan (7qts)...disconnect the return line and start the engine, shift through the gears and ..watch for air. Once air is spotted, shut the engine off and add 7 qts. Repeat this process until you have the system flushed.

b. After draining the pan add 10qts instead of the 7qts....disconnect the return line and start the engine, allow the old fluid to drain continuously into a measured container (shoot for 16qts)...without having to worry about the air.

If someone can answer these questions I would greatly appreciate it.

Thanks
 

Last edited by Bear Hunter; Nov 1, 2005 at 10:45 AM.
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Old Nov 1, 2005 | 10:43 AM
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"Transmission Fluid Return Line" Sorry about the typo in the subject line
 
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Old Nov 1, 2005 | 01:16 PM
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Nobody has flushed their tranny?
 
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Old Nov 1, 2005 | 04:12 PM
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Not yet, I was interested in what people said about this though.
 
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Old Nov 1, 2005 | 05:31 PM
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I can't believe no-one on the four boards I posted this on knows the answer!
 
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Old Nov 1, 2005 | 06:37 PM
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Take it to a dealer because it is easier to ahve them do it and it only takes about 30 min. They have a machine that hooks up to the lines so there is no mess and any tranny shop will probally have the same machine.
 
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Old Nov 1, 2005 | 06:51 PM
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Yeah...I priced everything out

Dealer wants $240 to do it and they only change the external filter.

I can save $100 doing it myself in addition to changing the internal filter.
 
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Old Nov 1, 2005 | 06:52 PM
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Ok here are some pics...maybe this will help:

Someone confirm which one is the Fluid Return Line. I think it is #1, but want to make sure:

http://www.truckblog.com/gallery/BearHunter/10414.jpg
http://www.truckblog.com/gallery/BearHunter/10415.jpg
http://www.truckblog.com/gallery/BearHunter/10416.jpg
http://www.truckblog.com/gallery/BearHunter/10417.jpg
 
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Old Nov 1, 2005 | 07:33 PM
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Alright,

Just FYI...found out the return line is #1

Still trying to get answers on the other questions.

Once I do You'all need to add this to the Tech Section...Tranny maintenance is just as important as changing your oil and fuel filters.
 
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Old Nov 1, 2005 | 08:07 PM
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Hey Bear i talked with a reputable tuning shop where i live and they said due to the check valve in the oil cooler line its not effective to flush the torqueshift tranny.
This is also why Ford changes the cooler when during tranny warranty work.

I too am torn about the best tranny service procedure .
 
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Old Nov 1, 2005 | 08:50 PM
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Originally Posted by LOOnatic
Hey Bear i talked with a reputable tuning shop where i live and they said due to the check valve in the oil cooler line its not effective to flush the torqueshift tranny.
This is also why Ford changes the cooler when during tranny warranty work.

I too am torn about the best tranny service procedure .
Thanks for the reply,

Hmmm...is that related to the internal thermostat where anything below 165 deg or so will not cycle the fluid? I have heard if you get the tranny hot enough you can do it. I called my dealership yesterday and asked them what they do and he didn't mention replacing the cooler...I think what they must have meant was changing the hose and clamp that connects to the cooler? Can anyone add to this?
 

Last edited by Bear Hunter; Nov 1, 2005 at 08:56 PM.
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Old Nov 2, 2005 | 10:08 AM
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Okay, after much research this is what I think I'll do:

Heat the tranny until I get above 165, drain the pan...add 10qts to get ahead of the pump, then disconnect the return line at the cooler so I can see how much is coming out into a measured container (shooting for 6-7 quarts..since I already added 10)... while I simultaneously add more SP.

I'll let you know how I do.
 
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Old Nov 2, 2005 | 04:31 PM
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Sounds like a pretty good plan.

I haven't flushed a 5R110 - but the 4R100 did require a change of the cooler, am pretty certain the 5R110 runs a similar system.

Keep us updated!
 
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Old Nov 2, 2005 | 04:41 PM
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Originally Posted by Bear Hunter
Okay, after much research this is what I think I'll do:

Heat the tranny until I get above 165, drain the pan...add 10qts to get ahead of the pump, then disconnect the return line at the cooler so I can see how much is coming out into a measured container (shooting for 6-7 quarts..since I already added 10)... while I simultaneously add more SP.

I'll let you know how I do.


WEll sounds good but how are you going to get the tranny to 165 degrees and then drain before it goes down?
I use an X-monitor which has a digital trans temp. Even when towing a 14,000 lbs. 5th wheel i rarely get over 160.
Are you going to do a massive burn out in your driveway to get that much heat in the tranny and then have yours tools and drain pans ready?

The only way i could replicate that is to tow through a steep pass and then drain at a rest stop at the top before the tranny can cool back down. Is this what your planning on doing?

I'm about to do mine again so i'm curious about the most effective method.
 
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Old Nov 2, 2005 | 06:16 PM
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Loonatic,

I hit 165-170 just normal driving turning my 40" tires...I paid close attention on the way home from work today...and it was pretty cool out. This was taking it easy like I always do. I figure, if I get up to operating temp (165-170) then drive it really hard for a while I can hit 180 easy.

We'll see how it works....the pan should drain pretty quickly (about 7qts)...then I will refill with 10. I'll be shooting to get 6qts out of the return by the cooler for a total of 16.
 

Last edited by Bear Hunter; Nov 2, 2005 at 06:34 PM.
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