Hey Nick, the diffs are stock as far as I know. I have a 14 bolt in the rear, which is kinda rare for a 1500. Can the 1st year in the tranny be made shorter instead?
I wanted to get the 60 rebuilt with heavy duty internals and was thinking of a small stall (1800-2300), but haven't found anything affordable.
Interestingly enough, all the local shops wanted an arm and a leg even when compared to Monster Transmission.
If the stock gearing is like 3:23 or 3:42, 3.73, you'll need to upgrade....Someone may have swapped it in prior to you owning or perhaps it was an option for that year/model...
For the 4L60E, I'd do the following (either you or your builder):
Converter Stall - Keep factory or at most 2200 - any more, you'll likely build too much heat to manage given the heavy vehicle plus once you go above 2200 RPMs you'll need to drop down to an 11" diameter which will triple/quadruple the cost of the converter.
Valve Body (cost ~30)
- Drop-in AFL Valve from Central Valve Bodies - replaces worn factory valve for improved line pressure management for all clutch packs and band/servo
- Dual spring in the AFL valve - increases AFL pressure to your solenoids for more consistent application circuit function (i.e. more clamping force to your clutch packs and band/servo)
- Block the TCC Regulator valve inboard to convert your PWM TCC apply to on-off - reduces heat and increases convert clutch life
- Block the 3-2 downshift valve inboard with a slug - take the spring and insert it inside the main AFL valve spring - crispens up 3-2 downshift at high RPMs
- Sonnax pinless forward accumulator
Accumulators (cost ~$35)
1-2 Accumulator - Install Sonnax pin-less accumulator
3-4 Accumulator - take your existing piston, grind off 1/3 of the legs then insert it upside down in the bore (leave perimeter seal off) then install new piston right side up, mesh the legs (install new seal) - that will block that accumulator 90% and give you a crisp, positive 3-4 shift
Spacer Plate / Check Balls (cost ~$10 if plate repair kit is needed)
-Drill out the 2-3 and 3-4 shift feeds to .093-.100; drill the 1-2 to .076-.080; drill the 2-3 exhaust to .093
- Repair the 1-2 check ball location using the Fitzall repair sleeve kit - install torlon check balls
Servo (cost ~$250 if both 2nd and 4th gear servo kits are purchased)
- 2nd Gear: Install a billet Sonnax Super Hold Servo kit (includes billet steel apply pin) or Superior Technologies billet servo
- 4th Gear: Sonnax super hold 4th gear apply servo kit
Pump (~$150)
- Remachine pump - install new pump internals, including rotor, slide, rotor guide, vanes
- Install Transgo's unbreakable pump ring kit for vehicles revving under 5000 RPMs - comes with ductile iron rings and improved priming spring for the slide
- Drill the drain back port in the pump body to 5/16" and install a Sonnax teflon coated bushing
- Install a teflon coated rear stator bushing as well
Band (~$60)
-Install an Alto wide red band for more clamping surface coverage on your reverse input drum - turn the drum to remove any warpage before installing the band
Forward Drum (
~$100)
- Install 97+ bonded steel/rubber pistons w/updated return spring assembly for the forward clutch
- Do an Alto, Raybestos or Borg Warner max pack for the 3-4 clutch - set clearance at .030-.045 - leave load release springs in if clearance is below .040
- Install Transgo's high rate return spring kit for crispter downshifts as well as to mitigate the likelihood of centrifugal apply at very high RPMs
Sun Shell ($125)
- Install Sonnax Smart Shell
Sun Gears
- Cut small grooves on the top and bottom of rear sun gear and planet-facing side of forward sun gear to allow more lube oil to flow to captured bearings and pinion gears in the planetary carriers
GM OEM Five-Pinion Planetary carriers (front and rear) - Optional (~$400-500)