SM465 to 4l80e or 700r4 Swap

[jgates122]

I have a 1982 c20, 350 with an sm465. I want to put an overdrive transmission in it and eventually do a mild build with the 350. I would've opted for the nv4500 but due to health reasons need an auto now. I am now trying to decide on a 4l80e vs a 700r4. I would probably rather a 4l80e because it is stronger, but I don't know how hard the electronics part is. But if I use a 700r4, will it hold up to the 350 with more power? I do not have any experience with transmissions, does anyone have advice on what would be best?

 

[CalSgt]

700R4 should hold up just fine to a lightly modified 350, my dad had a 700 in his K-20 with a 454 forever. That truck got swapped back to a small block and sold off, it was still rolling around on the same 700 for many years after.

Make sure the TV cable is adjusted and drive it like an adult…

 

[Catbox]

You can purchase a stand alone transmission controller to operate the 4L80.
Or if you are savvy, you can repurpose one of the GM computers to do the same work for much less.
For real cheap, you can run the transmission full pressure with some simple switches.

 

[Strick]

I regret to hear about your health issues and I hope that they will improve. The 700 should be fine if you will follow @CalSgt advice.

HS

 

[dragstews]

If you're pulling, might be better off with a 4L80/85 ...

 

[chris3353]

If you go 4L80, you may run into convertor dust cover issues. 99.5% of 4l80 came behind BBC. the oil pan arc area of the cover is much larger.

 

[adumars]

I swapped in a 4L80E in place of my TH400 (C20 Suburban). I used a US Shift Quick 2 controller- easy set up and works like a charm. I modified my TH400 dust cover to fit the 4L80E by drilling new holes. Best upgrade I've done. Night and day.