21’ Tahoe Tranny Fluid Flush vs Tranny fluid change and change filter

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ivin74

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Pricey. I just had my 10 speed in my 2021 Yukon serviced for $250. Just pan service and filter though. I think I'm going to do 30k intervals on my Yukon.
Thats cheap, around here it's $500.

You sure it wasn't just a flush? Oem oil and filter it self is $200 bucks.
 

jerry455

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I am putting a drain plug in mine. I tried to suck some out the other day and only got less than 2 quarts. I guess that side plug is not a straight shot into the pan. It is amazing that the directions tell you to shake up the new fluid before putting them in. I will probably wait until the spring to drop the pan. I have seen some videos on doing this. One of them used a pry bar on the exhaust crossover in stead of dropping it and sneaking the pan out.
 

fr8bil

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Picked up this one-owner 2018 Yukon Denali with the 6.2 and 10 spd. with 132k on it last Feb. but it was super clean and well cared for and very "tight". One thing I was unable to determine with CarFAX was to find any record of a tranny service so took it over to the nearby GMC dealer I've done business with for 14 years. Service advisor wildly under-quoted their tranny-flush price by $200 and told me the 10 spd. had an external filter. Once the service was complete and I got done bitching them out for the price mis-quote, they said this vehicle's tranny did NOT have the external, OEM filter on it. No idea if that was added later in the 2018 model year or if the guy had no idea what he was talking about.
 

jfoj

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The term "Flush" with regard to either hydralic power steering systems or automatic transmissions is typically a "Fluid Exchange". Usually there are no added chemicals or "flush" additives. A low pressure pump usually pushes new, fresh fluid though the sytem to "Exchange" the old, dirty fluid. With regard to automatic transmissions, there tends to be a lot of old dirty fluid stored in the torque converter, cooling lines and radiator/transmission cooler. You could expect a fluid "Flush/Fluid Exchange" on an automatic transmisson to require 2 times or even a greater amount of transmission fluid that just dropping the transmisson pan for a fluid service.

There are no negative effects of a properly performed automatic transmission "Flush/Fluid Exchange" assuming the proper transmission fluid is used and the level is properly set. Ideally a fluid exchange and a pan drop with a new filter is incorporated as well. Often the "Flush/Fluid Exchange" can be performed while the transmisson pan is off.

The majority of the stories on the Internet where people claim they had an automatic transmission "Flush/Fluid Exchange" then had a catastrophic transmission failure in short order is usually due to the vehicle owner not maintaining the transmission, realizing there may be a problem and then expecting a fluid service to correct hard part problems that were enevidible. New fluid that is of the correct type and set to a proper level will not cause premature failure of an automatic transmission. Usually the pin on the grenage has been pulled long before the fluid service is attempted in a last ditch effort to solve a much more major problem!
 

jerry455

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I wouldn't hesitate getting a fluid exchange at a GM dealer. When I had my 2018 Colorado with the 8 speed transmission, that was the fix for the shudder. Changing "black label" Mobil fluid for "blue label" Mobil fluid. What a difference. Since the forecast, tomorrow for the metro Detroit area is in the mid 50's and early rain, I will drop the pan and change filter and fluid on my 2021 Suburban 10 spd. I may even do plugs and wires.
 

jerry455

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Well, I did the fluid and filter today. It is really tight prying down the exhaust to get clearance for the pan. I also loosened the trans mount to get a little more clearance. The exhaust would bottom out on the trans crossmember. The fluid didn't look too bad, obviously longer than I would have done it, 79,000. Put filter and then pan on, filled it with 5 quarts, that's when it was coming back out and started it. Tried to shift and it would not, kept telling me, can't complete shift problem with trans. Set a check engine light. Stopped and started it 2 more times and then it started working. I had OnStar check the code for me, P0700 and P18AB. Not sure what they are exactly, will have to look in Service Information, but remote start works, which surprises me. One of these days I am going to find the engineer who did this trans and give them a piece of my mind. Stupid way to fill and check trans fluid.
 

RST Dana

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So, a local Caddy dealer in Cincinnati service writers tell everyone that asks, 10 speed Esky or Tahoe transmissions have “lifetime” fluid. I couldn’t believe it the first time I heard it. Called back a week later and a different person repeated the same crap. I wonder how GM would react to a warranty claim for failure with “no” trans fluid service history?
 

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