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

I need advice on my 2021 Tahoe LT with the 10speed tranny, Tranny Fluid Flush or Tranny Fluid Change and changing the filter? Currently it has 83,000 miles on it. The maintenance schedule under "Severe" conditions suggests changing both the transmission fluid and the filter, but for "Normal" driving conditions, it doesn't mention anything about changing or flushing the transmission fluid. I don’t tow and mostly do city/highway driving.

I’ve been quoted $300 for a simple transmission fluid flush, but if I opt for a full fluid change with a new gasket and filter, it’ll cost me double that. What is recommend? Is it overkill to go for the full service, or should I stick with just the simple flush? I want to make sure my transmission stays in good shape. I bought my Tahoe with 50,000 miles on it, so I’m not sure if the fluid was ever changed before.

Thank you everyone in advance

I would do it at 2x the "Severe" interval or less. I believe you need to do the filter too...so at that point, since the pan has to come off, not sure the benefit of the flush in addition, other than burning some additional transmission fluid.

Note, if you have 4WD, I highly recommend doing the transfer case as well, and the front and rear diff. All that stuff is cheap compared to buying new driveline components.

WalleyeMikeIII said:

I would do it at 2x the "Severe" interval or less. I believe you need to do the filter too...so at that point, since the pan has to come off, not sure the benefit of the flush in addition, other than burning some additional transmission fluid.

Note, if you have 4WD, I highly recommend doing the transfer case as well, and the front and rear diff. All that stuff is cheap compared to buying new driveline components.

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This. It’s hard for some folks to wrap their heads around, but unless you’re doing severe workloads your chances of causing a problem are generally higher than solving a problem that is yet to exist messing with it.

Curious was a dealer that quoted that? Some I know of will even avoid doing it at all unless you’re exhibiting problems.

iamlegion said:

This. It’s hard for some folks to wrap their heads around, but unless you’re doing severe workloads your chances of causing a problem are generally higher than solving a problem that is yet to exist messing with it.

Curious was a dealer that quoted that? Some I know of will even avoid doing it at all unless you’re exhibiting

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iamlegion said:

The dealership said their standard procedure is to do a flush, but my mechanic could do both a flush or a full fluid change with filter. I wanted to find out which option is more beneficial since I'm not sure if the transmission fluid was flushed at 50,000 miles.

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I have never had a transmission flushed. Have dropped pan and changed filter then refilled with about 7 qts. of oil. done.

Jm08 said:

I need advice on my 2021 Tahoe LT with the 10speed tranny, Tranny Fluid Flush or Tranny Fluid Change and changing the filter? Currently it has 83,000 miles on it. The maintenance schedule under "Severe" conditions suggests changing both the transmission fluid and the filter, but for "Normal" driving conditions, it doesn't mention anything about changing or flushing the transmission fluid. I don’t tow and mostly do city/highway driving.

I’ve been quoted $300 for a simple transmission fluid flush, but if I opt for a full fluid change with a new gasket and filter, it’ll cost me double that. What is recommend? Is it overkill to go for the full service, or should I stick with just the simple flush? I want to make sure my transmission stays in good shape. I bought my Tahoe with 50,000 miles on it, so I’m not sure if the fluid was ever changed before.

Thank you everyone in advance

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"Flush" is a bit of a misnomer. It's the same process for all modern transmissions at most quicklube shops and dealers. They disconnect the cooler lines, connect them to a fluid exchange machine, start the engine and let the transmission's pump circulate the fluid through the machine. Sometimes at this point, they will add a detergent and let the fluid circulate through the machine's contaminant filter loop for 3-5 minutes. When the tech is ready, they change the machine mode to capture the old fluid while drawing the new fluid in, replacing it with the correct quantity of new fluid. Then they do a level check, reconnect the cooler lines, and you're on your way. I've always had my transmissions done this way every 20-30K (depending on towing duty) and never had a problem. Every 40-60K, I drop the pan and replace the filter instead of having the fluid fully exchanged.

Knock on wood, I haven't had a transmission fail that's been maintained this way. I did have a valve body fail, but it was a common issue with that transmission, and an updated valve body fixed the issue. I credit this process for keeping a 4L30E (usually good for no more than 150K) going for 300K with no issues.

blondie70 said:

I have never had a transmission flushed. Have dropped pan and changed filter then refilled with about 7 qts. of oil. done.

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This is the way. You won’t get 100% of the fluid out but it will be the majority. I’ve actually heard that flushing a transmission is not a good thing.

I have never done a tranny flush, I always go with the total change out including the filter and have been never experienced transmission failures on any of my vehicles. In my fleet I have 2 high mileage vehicles one is a Honda with 155k miles the other is a yukon with 197k. I can take either one across the US and don't have to worry about getting stranded.