@NickTransmissions I think my best bet is to rebuild it with some better parts. I know I’m mechanically inclined enough to do it, I mean I’ve done engine swaps and rebuilt engines with my dad. ( I know a transmission is a totally different ball game though) I looked at one of your other threads and it lead me to believe that it’s the forward input sprag that took a crap. For a proper rebuild what parts will I need in a kit? Because some kits have more parts than others, and some have different parts than others, also what parts should I upgrade for daily driving and off-road use? The truck is completely stock besides for the lift and 35’s, and I plan to keep it that way I just want to be able to beat on the trans (such as burnouts, putting to the floor all the time and some light rock crawling/ trails, and some towing) and not have to worry about it taking a dump on me. I hear a better drive shell and 5 pin front and rear planetary sets. Another question I have is should I use the torque converter that was previously on it. The transmission was rebuilt in 2018, the torque converter is brand new and there is no “glitter” in the trans fluid.
Did you upgrade your final drive ratio or do you still have the factory ring and pinion gear set installed?
If you still have the OE final drive ratio, you're going to be going through transmissions like other folks go through oil filters. Your 3-4 clutch pack will continuously burn up due to lack of mechanical leverage when in OD and attempting to accelerate.
Upgrade your ring and pinion in the diff(s) before doing anything with the transmission!!!
4.56 to 4.88 gears is what I recommend.
That said, I'll be putting out a video on a typical 4L60E build profile in a week or so but for your intended usage, you want the following:
- Cal Kit (filter, paper/rubber, gaskets, seals, o-rings, etc)
- steel module (Kolene coated steels in the LR/Rev Input and 3-4 packs)
- Alto Power Pack for your 3-4 clutch (9 frictions and 8 steels vs the factory stack which is 6/5)
- Run either Alto Reds or High Energy
- Kevlar or Red wide 2-4 band
- Complete bushing kit
- Complete bearing kit if major damage or overheating occurred, otherwise existing bearings are usually fine to reuse but check them to be sure
- Heat treated sun shell (Sonnax Smart Shell is the best on the market and def worth the extra $100 or so over the factory replacement heat treated shell)
- Pair the Smart Shell with a 2003+ reaction shaft and bearing and you've rollerized the entire middle of the case)
- Input sprag assembly (if your sprag rolled/broke apart, you'll need a new sprag gear assembly, not just the one-way clutch element itself)
- Low roller clutch
- Pump rotor guide, vanes
- Pump resurfacing (body and cover)
- Transgo Unbreakable pump ring kit is a great little upgrade for a few bucks, comes with a better slide priming spring
- Sonnax HP1 Performance Pack
- Corvette 2nd gear servo
- Sonnax wide rear sun gear bushing
- All electronics/electrical components like harness, solenoids, pressure switch manifold, MLPS and VSS
- OEM GM 5 pinion rear planetary carrier (if you can afford it, install the 5-pinion front planet as well)
Assuming you're going to keep a stock stall speed for your TC, drill your clutch feed orifices as follows:
- 1-2 shift: .080-.086
- 2-3 shift: .093
- Band release: .093-.100
- 3-4 shift: .093
- Low Reverse feed: .080-.086
You'll need to research prices, etc for all of the above but that should get you started on a build that can take a bit of a beating off-road yet still function as a daily driver. Add the 4L60E ATSG manual to your shopping list if you haven't already...
