If I never replaced the transmission Thermal Bypass Valve, should I be running to the dealer ASAP?

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TahoeFL2017

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2017 Tahoe LT, 6 speed, never replaced this as far as I know - should I be concerned?

I don't tow, and Florida is pretty flat, so not a whole lot of stress ln my trans.
 

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2017 Tahoe LT, 6 speed, never replaced this as far as I know - should I be concerned?

I don't tow, and Florida is pretty flat, so not a whole lot of stress ln my trans.
if there are no issue's then no but it's something that could be done to perhaps help in the long run.
good maintenance is helpful, don't take it for granted that the transmission fluid will be good for 100k per the owners manual. that's a farce.
 
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TahoeFL2017

TahoeFL2017

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I had all fluids changed at around 50k miles, so 30k on what's in there now.

Appreciate the reply though, i want to keep this truck long term so do whatever i can.
 

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Wes
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I had all fluids changed at around 50k miles, so 30k on what's in there now.

Appreciate the reply though, i want to keep this truck long term so do whatever i can.
With the exception of the front & rear differentials I do all fluids annually and the diff's every other year. so coolant, brake, trans. the k2's are electric steering so nothing to do there. I also throw in some injector cleaner at least every 3 months and keep the throttle body and maf clean about the same although those can probably go a bit longer maybe 6 months to a year it can depend on how dirty the environment is that you frequent. for instance dirt roads are terrible for the intake and so more frequent cleaning should be done.
 

NickTransmissions

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What rational would anyone have for doing this? Why would anyone waste the dollars or the time?
Major heavy duty use (lots of towing/hauling). I recommend annual trans fluid changes for older units running Dex3 in HD applications but for daily driving/stock level usage I recommend once every 30-34k for transmission fluid and perhaps every 50-70k or so for the diff(s), regardless of fluid type used (you have a little more leeway with synthetic) but intervals should never be like 100k or more between changes, IMO.
 

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Wes
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What rational would anyone have for doing this? Why would anyone waste the dollars or the time?
lol, because I follow a severe duty cycle and I tend to keep my vehicles for a long time, I don't drive it until breaks and never maintain it then and then dump it on some poor soul that now has to go spend a ton of money fixing stuff that should have been done already.
also i drive like the wife's water just broke and it's time
 

steiny93

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lol, because I follow a severe duty cycle and I tend to keep my vehicles for a long time, I don't drive it until breaks and never maintain it then and then dump it on some poor soul that now has to go spend a ton of money fixing stuff that should have been done already.
also i drive like the wife's water just broke and it's time
my rational:
1) you aren't doing anything 'severe' with your 1500; no plow, no commercial work, it isn't severe
Here is how GM describes severe: Extreme service. For vehicles mainly driven off road in four wheel drive or used in farming, mining, forestry, Department of Natural Resources (DNR), or snow plowing.
2) high frequency fluid change doesn't equate to long life; driving style matters, dumping still in spec fluid doesn't do anything magical
3) unless you are piling a ton of miles, annual is beyond even the severe schedule, per GMC's: oil @ 7500, trans & transfer @ 45k, cooling @ 150k, the severe schedule doesn't even list brake fluid

If it makes folks feel better, by all means dump the fluids every week.
But the reality is that changing fluids matters near zero if you are close to manufacturer recommended. If you disagree go dig around fleet maintenance schedules for light duty vehicles within fleets that run out to say 250k (don't look at 100k fleets, to short of a duty cycle, anything will get to 100k). Those fleets are incented to minimize major break issues within the service cycle of the vehicles, they are zeroed in on maintenance to get there and they have the data to back it up.
 

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my rational:
1) you aren't doing anything 'severe' with your 1500; no plow, no commercial work, it isn't severe
Here is how GM describes severe: Extreme service. For vehicles mainly driven off road in four wheel drive or used in farming, mining, forestry, Department of Natural Resources (DNR), or snow plowing.
2) high frequency fluid change doesn't equate to long life; driving style matters, dumping still in spec fluid doesn't do anything magical
3) unless you are piling a ton of miles, annual is beyond even the severe schedule, per GMC's: oil @ 7500, trans & transfer @ 45k, cooling @ 150k, the severe schedule doesn't even list brake fluid

If it makes folks feel better, by all means dump the fluids every week.
But the reality is that changing fluids matters near zero if you are close to manufacturer recommended. If you disagree go dig around fleet maintenance schedules for light duty vehicles within fleets that run out to say 250k (don't look at 100k fleets, to short of a duty cycle, anything will get to 100k). Those fleets are incented to minimize major break issues within the service cycle of the vehicles, they are zeroed in on maintenance to get there and they have the data to back it up.
driving it like a race car is not mentioned anywhere?
at what temp does the brake fluid begin to break down?
I will tell you 400-600 deg. If you think I don't get my brakes that hot just driving somewhat adventurously then you are mistaken
I can get them heated up pretty good just going a mile or 2 down the road.
you have to keep in mind GM wants to you to break down (eventually) that's how they stay in business, which is why parts have a rated life expectancy.
if you don't think that driving a vehicle vigorously is considered severe then you are sadly mistaken
even the transmission shop that built my transmission requires me to have the fluid changed annually to maintain my warranty, because they know better.
and I change my oil every 3k lol (god forbid)
in all reality I drive my vehicle harder than any of those industries you mentioned.
severe duty does not have to be "by the book" definition
 

steiny93

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driving it like a race car is not mentioned anywhere?
at what temp does the brake fluid begin to break down?
I will tell you 400-600 deg. If you think I don't get my brakes that hot just driving somewhat adventurously then you are mistaken
I can get them heated up pretty good just going a mile or 2 down the road.
you have to keep in mind GM wants to you to break down (eventually) that's how they stay in business, which is why parts have a rated life expectancy.
if you don't think that driving a vehicle vigorously is considered severe then you are sadly mistaken
even the transmission shop that built my transmission requires me to have the fluid changed annually to maintain my warranty, because they know better.
and I change my oil every 3k lol (god forbid)
in all reality I drive my vehicle harder than any of those industries you mentioned.
severe duty does not have to be "by the book" definition
driving like a race car in a 1500
gotcha, suddenly all makes sense, carry on
 

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