What it says on the tin really, How reliable long term are the 4L60E's Mounted in 1999-2001 S10s, And are there more reliable ones that can be swapped in without too much difficulty to the 4.3L. Mine is a rebuilt unit that has about 50k or less Miles on it and i plan on Making this vehicle my Daily driver so i'd like to know what im in for long term.

 

If it was rebuilt by a good shop and well maintained, I would think you should be able to get at least 150,000 miles out of it. If you tow, you should add a transmission cooler and remember never to tow in over-drive.

There is the 4L65E that was designed for use with the 6.0L and perhaps the 4L70E could be installed but there could be issues with input shafts and the bell-housings. But the bell housings are removable.

 

Sounds about right, looks like im adding a transmission cooler somewhere along the line then as i do plan on using it as a Utility vehicle, and for general longevity of the transmission its probably a good idea anyways.

 

Heat is the number one killer of ANY trans. Factory setup has the trans fluid going to the radiator, basically passing through a tube that runs through the antifreeze in the side tank, but it's not much of a cooler per say... Putting on a beefy cooler is a great upgrade to any vehicle, and the 4L60E will thank you in the long run

 

Any Recommendations and / or guides? Im fairly new to "fullsize" automotive work so im not sure where i'd start.

 

I would think that most any transmission shop could install one for you. They are a common add-on. This webpage has some useful information geared toward those who two trailers and as such put more strain on their components. https://www.etrailer.com/faq-about-e...n-coolers.aspx

Something else you can do is monitor the temperature of the transmission fluid. I do this because I tow a boat with my Blazer. Our transmissions have a fluid temperature sensor in them but they are not hooked up to our dash like they were in the full-sized trucks that used the same transmission. The goal is to keep the tranmission fluid temperature below about 200'F - 210' F. My solution was to use a real-time OBD (on-board diagnostics) reader to monitor the transmission temperature. There are several of these but I chose this one (Ultra-Gauge) and it has been easy to use and can also check the simple "check engine" codes. UltraGauge OBDII Scan tool & Information Center

FYI: I also installed an oversized radiator but that is probably overkill for most. You can find the link to my write-up on it in my build-thread (linked below).

 

I wonder if its possible to find an actual Gauge for the Transmission temp and somehow add it in somewhere either as its own independent gauge or somehow integrate that led panel under the Tach.

 

That would be a cool mod.

I'm guessing that it is something normally done through the body control module. There might be a way to tap into the wiring that goes directly to the temp sensor and then connect it to a OEM style gauge. I'd love to do that for mine.

 

Trans fluid starts to break down and may foam at 200 degrees
At 210 degrees clutch pack damage and seals harden and their break down starts to occur.
Ideal transmission run temps are 140 to 170
standard engine temps usually run at 190 to 195 so just the radiator cooler gives 5 to 10 degrees before damage may start.
When adding a remote cooler either add a stand alone or in the fluid return line after the radiator cooler.
I haven't seen or a way to add a led in the inst. panel but there is stand alone gauges that use their own sending unit that mounts in the transmission.

 

Plan was to mount it on the Return line, so the fluid runs the length of the radiator first, then gets a good few hairs colder before being sent back, and probably an electric fan driven off an always on accessory power rail, i dont much like transmission work so whatever i can do to keep it cold im doing it.