Transmission?

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Sparky75013

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I have a couple of questions that I'm hoping someone can help me with.
First, how can I determine exactly which transmission is in my vehicle? Is there a way to identify it by the VIN, transmission tag, RPO code, or another method?
Second, if I replace the transmission with a factory OEM unit that has the same part number, is there any programming or relearn procedure required for the ECU/TCM? Or is it essentially a remove-and-replace installation?
If programming is required, what all needs to be done, and is it something that can only be performed by the dealer, or can it be done with a capable scan tool?
The vehicle is:
2018 GMC Yukon XL SLT
5.3L
2WD
The 7th digit in the VIN is a K if this helps

Lastly, What is your opinions of add-on accessories like this additional filter system like this one - https://www.summitracing.com/parts/...yKG1Zi1PIauA-NBeebDQ3fSxCEpJinhQaAoRDEALw_wcB
Are they a bad idea?
Thanks in advance for any advice.
 
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Joseph Garcia

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RPO codes will tell you what was originally installed in the truck. MYC is the 6 speed transmission, and M5U is the 8 speed transmission.

Whoever replaces your transmission (assuming that it is a professional who's business involves replacing transmissions) will program the transmission upon installation.
 
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Sparky75013

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Rygrego

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Thanks, No one is commenting on the add-on filter. Should I take that as a sign of disapproval?
To be honest I didn't even notice that comment until I looked back. I don't see where you can go wrong with more filtering. The main thing I would recommend is improving the trans cooling system. #1 either eliminate or ungrade the transmission fluid thermostat and #2 add an additional cooler. I did the Mishimoto transmission cooler and could not be happier. Towing a 6000 lb boat around Arizona in 110 degree heat and my trans temp never exceeds 170 degrees when prior to the upgrades it was 205 degrees just driving under light load.
 
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Thanks, No one is commenting on the add-on filter. Should I take that as a sign of disapproval?
I installed this very unit on mine. Important to note that unless you bypass the thermostat (I did) it will only filter when hot. I did this while replacing the pan / internal filter. My hope is that as long as I keep my 10 micron spin on filter changed, I shouldn’t really need to drop that pan again. I also hope that if the TCC bites the dust, the spin on can keep the rest of the tranny clean enough that I don’t need a complete rebuild. Every time I do a drain and refill now the fluid is clean as it went in. Wish I would have done it brand new.
 
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Sparky75013

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I installed this very unit on mine. Important to note that unless you bypass the thermostat (I did) it will only filter when hot. I did this while replacing the pan / internal filter. My hope is that as long as I keep my 10 micron spin on filter changed, I shouldn’t really need to drop that pan again. I also hope that if the TCC bites the dust, the spin on can keep the rest of the tranny clean enough that I don’t need a complete rebuild. Every time I do a drain and refill now the fluid is clean as it went in. Wish I would have done it brand new.
Do you have the link for the one that you installed? How does/did it connect before the T-stat?
 
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Sparky75013

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Thanks for all the replies, I will follow the recommended "drop the pan" and replace the filer and replace the pan with one that has a drain plug. I have 132K miles on this and want to know one more thing - do I switch to Mobil blue label LV fluid since I have the pan off or stay with the standard ATF? IF I switch, I would assume this would be a two change process, change the fluid, drive for 200 miles, and then change again to get as much fluid swapped from the torque converter.
 
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Do you have the link for the one that you installed? How does/did it connect before the T-stat?
I think I used the same one you linked, or very similar (looks the same). It doesn’t connect before the thermostat, that’s why you have to bypass it with something like the sure cool. It connects via the cooler lines. The kit is made for you to cut the “out” line to the cooler and splice it in there. Each line has a rubber section you can slice into. I bought a series of adapters to connect mine via the quick connects at the cooler, but it cost a bit more and does add complexity.
 

Rygrego

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Quick question on the trans cooler, did you notice any increase in engine operating temps due to the trans cooler sitting in from of the radiator?
None whatsoever. The cooler is mounted on the struts just forward of the condenser and not touching it. So plenty of air movement around the cooler without affecting the air flow to the condenser or radiator. My engine temp reads 210 no matter the outside temperature and my trans temp never exceeds 170 degrees. Not the cheapest but by far the best I've ever encountered. The package contained everything needed for the specific application.
 

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