Transmission question

[15 Z71]

I know this has been talked about before. But my question is I have 67,000 on my truck and never transmission service done. It shifts smooth and great now. What I have read on hear is just to have trans fluid and filter changed NOT to do the trans flush. Has any one had problems after having fluid and filter changed? Thank.

[rav3]

1 minute ago, 15 Z71 said:

I know this has been talked about before. But my question is I have 67,000 on my truck and never transmission service done. It shifts smooth and great now. What I have read on hear is just to have trans fluid and filter changed NOT to do the trans flush. Has any one had problems after having fluid and filter changed? Thank.

Lots will have different opinions on this, so here goes mine. I usually just doe a "drain & fill" so to speak. On the my Silverado(s), I suck out about 5 qts from fill tube & refill with AC Delco Dexron VI. This newer Dexron VI lasts much longer than the old stuff (DexIII). The filler just filters out the big stuff & won't need changing for a while, IMO. Changing the fluid replenishes some of the additives that have degraded from heat. I always add LubeGard Platinum that helps the friction modifiers. I do this drain & Fill about every 30k or so. Some do it every oil change. That way it keeps the transoil fresh. Good luck with your decision. FYI, this only takes me about 20-30 mins & I don't have to get under the truck. Also look at drain & fill transfer case, front & rear differentials. Don't forget to flush you brake fluid cause it attracts moisture.  At least suck out old from the brake reservoir & replace with DOT4. Simple maintenance that your truck will like. 

[servons09]

I'm in a similar situation as OP. Bought my 2015 5.3L certified used at just over 63,000 miles. I'm now at 73 and change. Since it was certified used (only one owner before me) the mechanics inspecting fluids for Chevy's certified used 150 point inspection, marked the transmission fluid at decent health. Trans fluid has never been flushed or changed. Having checked all the fluids right after purchase I was able to confirm their grading. That said, I'm wondering what route OP went with. Personally on my own rig I'm leaning towards a flush since the transmission fluid (I feel) is still in that threshold of a flush, but wondering what route OP went with.

Edited March 28, 2021 by servons09
Grammar

[silveradosid]

i had gm do the fluid replacement or flush what ever you want to call it at 76k miles and i am now at 130k. going to do it again this week

[DeePa]

I did a dealer flush and fill at 50k and dropped the pan, changed the filter, and refilled what was lost. I will just run it until it lets go at this point. 

[Grumpy Bear]

Did my first service at 50K and by 125K have done several more. Details of the service records recently posted in my build thread. Won't duplicate it here. Drop and fill until I installed PML pan with drain. That got old quick.  

[servons09]

Thanks for the input everyone. Updating this incase anyone out there might be in a similar situation. I took my 5.3 to a mechanic I've had success with (I don't trust the dealership like I do this local mom and pop shop) and ended up doing a complete fluid flush including pan drop and clean, new gasket, new filter etc. After driving my rig highway, up hill down hill and side street, I can confidently say she shifts just as good if not better than she did when I first got her. My initial concern was that the truck's transmission was at the point where flushing might do more harm than good. That said, her past owner seemed to have taken good care of her, and I think its worth mentioning to anyone in a similar situation that I asked my mechanic to flush the  transmission via hand/ transmission pump, and not anything high pressure. Fluid-wise I went with standard ac ACDelco Dexron VI stuff. Very pleased with the outcome despite her mileage teetering in that gray area of flushing vs. pan drop.