I had started a topic in a different sub-forum and got into the ATF stuff a little bit. However, it was off-topic so I decided to post something here instead. Here is my dilemma:
My parents just gave my daughter their 2002 Chevrolet Trailblazer with the i6. It has 152K miles. It has been well-maintained EXCEPT that my dad never does transmission fluid changes on his vehicles. Ever. The transmission shifts fine as far as I can tell. The fluid is dark, but doesn't smell burnt.
Basically, I've read lots of conflicting advice on the internet. Many people say that in a transmission that old/high mileage that it is safest to leave it alone. Others say the opposite. I just don't want to create a headache for myself a few months before my daughter goes to college. I don't want a big expense. Of course, I want to do what is best for the car too. I change my ATF in my other vehicles every 30K miles.
As I see it, I have 5 courses of action.
1) Do nothing and let it ride.
2) Do a flush. This seems like the most risky option.
3) Have my mechanic do a pan drop, replace the filter, and replace the 5 qts of fluid that are supposed to come out of the pan. I'm not particularly comfortable doing a pan drop myself.
4) Using my hand pump, get as much as I can out. Drive around. Do a fluid swap again. This way I'll get most of the fluid out quickly and won't have to drop the pan. I've read that these filters regularly clog and it is probably a waste of time to drop the pan and change them. I know my Toyota only has a screen, so filters must not be THAT necessary.
5) Use my pump and replace the fluid gradually (say 1 qt every 1000 or 3000 miles).
It specs DexIII and I'd bought several quarts of Mobil 1, which is what I have used for years on my Tacoma that specs DexIII. If I do end up replacing the fluid in some fashion, is there a better choice for a high mileage tranny?
In a nutshell, I'm confused and am having trouble telling fact from fiction. There *ARE* quite a few horror stories about people changing the fluid in their (supposedly) perfectly fine transmission only to have it fail shortly thereafter. There are lots of people that say this is a coincidence, but that seems a bit cavalier to me. There wouldn't be that many examples of failures if there weren't some truth to it.
Anyway.....HELP! Sorry for posting again. I'm just trying to make the best decision for this vehicle and it does not seem at all clear cut. I've searched and read everything I could find on the subject...and it hasn't really helped. Maybe there are those that have done this exact thing to this transmission and can comment.
My parents just gave my daughter their 2002 Chevrolet Trailblazer with the i6. It has 152K miles. It has been well-maintained EXCEPT that my dad never does transmission fluid changes on his vehicles. Ever. The transmission shifts fine as far as I can tell. The fluid is dark, but doesn't smell burnt.
Basically, I've read lots of conflicting advice on the internet. Many people say that in a transmission that old/high mileage that it is safest to leave it alone. Others say the opposite. I just don't want to create a headache for myself a few months before my daughter goes to college. I don't want a big expense. Of course, I want to do what is best for the car too. I change my ATF in my other vehicles every 30K miles.
As I see it, I have 5 courses of action.
1) Do nothing and let it ride.
2) Do a flush. This seems like the most risky option.
3) Have my mechanic do a pan drop, replace the filter, and replace the 5 qts of fluid that are supposed to come out of the pan. I'm not particularly comfortable doing a pan drop myself.
4) Using my hand pump, get as much as I can out. Drive around. Do a fluid swap again. This way I'll get most of the fluid out quickly and won't have to drop the pan. I've read that these filters regularly clog and it is probably a waste of time to drop the pan and change them. I know my Toyota only has a screen, so filters must not be THAT necessary.
5) Use my pump and replace the fluid gradually (say 1 qt every 1000 or 3000 miles).
It specs DexIII and I'd bought several quarts of Mobil 1, which is what I have used for years on my Tacoma that specs DexIII. If I do end up replacing the fluid in some fashion, is there a better choice for a high mileage tranny?
In a nutshell, I'm confused and am having trouble telling fact from fiction. There *ARE* quite a few horror stories about people changing the fluid in their (supposedly) perfectly fine transmission only to have it fail shortly thereafter. There are lots of people that say this is a coincidence, but that seems a bit cavalier to me. There wouldn't be that many examples of failures if there weren't some truth to it.
Anyway.....HELP! Sorry for posting again. I'm just trying to make the best decision for this vehicle and it does not seem at all clear cut. I've searched and read everything I could find on the subject...and it hasn't really helped. Maybe there are those that have done this exact thing to this transmission and can comment.
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