Complete transmission flush

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joezek

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I kind of messed up. My local commercial parts supplier told me to use Amalie synthetic universal transmission fluid after I specifically asked for Mercon SP. Allegedly all the mx shops use it... Well now I have a ten seconds delay into drive and reverse until its warmed up.

So I need to know how to completely flush out the fluid including the converter
 

07navi

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From what I read there is a valve that prevents a full flush unless it is extremely hot, also I doubt if that "universal" fluid is what is causing your forward and reverse delay......but I have been wrong before.
 

Shantheman73

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I kind of messed up. My local commercial parts supplier told me to use Amalie synthetic universal transmission fluid after I specifically asked for Mercon SP. Allegedly all the mx shops use it... Well now I have a ten seconds delay into drive and reverse until its warmed up.

So I need to know how to completely flush out the fluid including the converter

You might not want to do this...but given the delay in shifting...I’d take it to a dealer or a trans shop and have them do the full flush to ensure you’re getting all the wrong fluid out.


Sent from my iPhone using Tapatalk
 

llhoneymoons

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I kind of messed up. My local commercial parts supplier told me to use Amalie synthetic universal transmission fluid after I specifically asked for Mercon SP. Allegedly all the mx shops use it... Well now I have a ten seconds delay into drive and reverse until its warmed up.

So I need to know how to completely flush out the fluid including the converter


Why were you putting fluid in? You shouldn't need to add any unless you have a leak. If you have a leak and were running the unit low...
 

lbv150

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For trans oil, Valvoline Maxlife full synthetic is what I run in everything. As others have said, you can change the oil but the lag problem most likely will still be there. Something else going on, if not low oil level.
 

MrBlargMan

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Joezek, did you get your issue straightened out?
What did your fluid level turn out to be?

07Navi, there is a thermostat on modern transmissions. Just like on your engine, it is designed to keep the unit at its designated operating temperature. It is a simple procedure to raise the transmission fluid to a temperature high enough to open the thermostat and any competent service technician with the correct equipment should be able to perform a full flush on one of these units with zero issues.
 

Kevin08

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I just finished a trans swap on and 08. No it is not easy to get the thermal valve to open. Ford Tech Makuloco said one would have to sit and high rev the motor to the point of risking transmission damage to get the system to circulate. I have to agree now that I’ve spent a week getting mine to take small sips at a time until I finally got 11 quarts in it. It keeps showing full but I’m cautious because everything I’ve read states it should take 12-13 quarts. But no, the thermal valve does not open or not open enough just idling. After I finished my swap, I watched an Australian mechanic rebuild a 6R80 and he said since they don’t have cold weather in his area he always throws that thermal valve away. I’m thinking well sh*t, wish I’d known that was an option. I had the valve body out to replace the bridge seal.
 
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max78

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Joezek, did you get your issue straightened out?
What did your fluid level turn out to be?

07Navi, there is a thermostat on modern transmissions. Just like on your engine, it is designed to keep the unit at its designated operating temperature. It is a simple procedure to raise the transmission fluid to a temperature high enough to open the thermostat and any competent service technician with the correct equipment should be able to perform a full flush on one of these units with zero issues.


How do they raise the temp? That one Ford tech on YouTube says the exact opposite of what you are saying. My Ford tech also said it was pointless because of the thermostat. Their machine does not heat the fluid, and you can’t force the fluid. Just curious because there are a lot of techs that say otherwise. I would love to hear what they do to overcome the thermostat.
 

lbv150

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Thermal valve is there for a reason....the clearances in a modern servo transmission need the oil to be at a certain temp for viscosity and circulation.
 

07navi

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They need to quit playing games and put the plugs back in the converter and pan. Next there won't be a pan and they will call it a lifetime or throw away trans (Biden will like that).
 

max78

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They need to quit playing games and put the plugs back in the converter and pan. Next there won't be a pan and they will call it a lifetime or throw away trans (Biden will like that).

1999 Honda CRV is exactly that. There is a drain plug for the trans fluid.

But there is no serviceable filter or anything like that. We have put just over 210k on it so far.
 

07navi

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My 2000 Excursion had converter and pan plug plus a lifetime oil filter. Ford is going backwards...ridiculous.
 

MrBlargMan

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How do they raise the temp? That one Ford tech on YouTube says the exact opposite of what you are saying. My Ford tech also said it was pointless because of the thermostat. Their machine does not heat the fluid, and you can’t force the fluid. Just curious because there are a lot of techs that say otherwise. I would love to hear what they do to overcome the thermostat.

A simple and light "brake torque", or throttle application of around 1200RPM with the vehicle in gear while holding the brakes, will safely heat the fluid in the torque converter as the engine driven impeller is spinning, but not transferring any motion to the turbine. Once the fluid has reached operating temperature, the thermostat will open, and it will be free to flow into your fluid transfer apparatus. A lot of newer flush apparatus even include hardware for transmission thermostat bypass on applicable applications.
 
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