1999 S10 4.3 4l60e trans. 76k on truck we've had it since 2018 when it had 52k. I believe this was the original ATF based on the lack of maintenance the truck had received when we initially got it. Filter/gasket were identical to the GM Genuine replacement I had to put back in it. It took 4.5 qts and I used Maxlife. No issues shifting before or after. Really impressed 25yo fluid looked this good even with the low miles. Picture is how the inside of the pan looked when I dropped it.
1999 S10 ATF fluid and filter change (original ATF)
- Thread starter nwjones18
- Start date
Looks good 
You should've gotten an aftermarket pan with a drain plug, so that future ATF changes are much easier
You should've gotten an aftermarket pan with a drain plug, so that future ATF changes are much easier
I actually played with my fluid extractor for the first time before I dropped the pan, so next time I'll just suck out a gallon and replace it. No mess! Wanted to see the pan and change filter this time though.Looks good
You should've gotten an aftermarket pan with a drain plug, so that future ATF changes are much easier
My personal views are drop the pan at least once, change out the filter using GM Genuine and from there use the fluid extractor going forward.
You really only need to drop the pan once because factory break in materials are caught in the filter, but after that it is not necessary every time, if the filter clogs up it is because your transmission is junk.
Service it every 35-45,000 miles.
It's only unserviced aged units I see the normal clutch/friction break-in debris clumped together like that, If the pan would've been dropped & cleaned 15 years ago that same material would be evenly spread out.
In that time frame much of the GM factory fill was sourced from Petro Canada. It was good stuff. Not sure what the base oil was.
Petro Dex 3 flowed better at 40 below than the original Dex VI which was "interesting".
I've got a 99 Sonoma. Thanks to Wool Wax it's gonna outlive me.
Petro Dex 3 flowed better at 40 below than the original Dex VI which was "interesting".
I've got a 99 Sonoma. Thanks to Wool Wax it's gonna outlive me.
Unless you're towing or doing truckpulls, anything like Valvoline Maxlife or even better TranSynd should easily be a lifetime fill after the first change.Looks good
You should've gotten an aftermarket pan with a drain plug, so that future ATF changes are much easier
At best Maxlife is a 100k fluid with a flush.
