I am considering going through this transmission when I pull it. Any thoughts? My plan is a Sonnax HP kit in the valve body and internally dual feeding it. If I go with the Sonnax kit does the added line to lube hole still need to be drilled? I feel it is good insurance to do the lube system modifications for the roller, sprag clutches. Maybe use the earlier style overdrive roller clutch if it drops in without machine work. I will rollerize the output since I can easily obtain those parts. I do not see a reason to go with anything special on the clutches or steels. I also feel like the stock geartrain parts are more than adequate for the torque I am making. No need for strongers shafts or the extreme hubs or anything crazy like that. I would love a 2.96 or 2.75 1st gear, but I see no reason to spend that kind of $$$ given I will be going to a 6L90E in a year or two anyway. I want to keep the unit as a spare for the Tahoe or put it in the G20 van later, so it makes sense to me to make it solid for the future. Neither the Tahoe or the G20 weigh what the Express van weighs, so 2.48 1st is perfectly adequate for them.
- Sonnax PR valve: no line to lube hole (do all the other lube mods)
- Sonnax LB1-4L80E
- Earlier roller clutch usable if you swap in an earlier OD planet (only the outer race changed)
- Rollerize the rear of the case
- replace all bushings
- replace all bonded pistons
- BW or Raybestos stock frictions are fine - replace steels as needed otherwise just prep your existing ones
- replace all one way clutches (prep the int outer race w/400 grit sand paper)
- replace all electronics
- Install a wide forward drum bushing (make sure your drum's inner dia has no sealing ring grooves cut in or bore/ream and sleeve it if so)
- Sonnax 1-2 and 2-3 shift valve springs, AFL and TCC valves
- check pump gear face to body working surface - machine if needed / replace gear set if necessary
- use an A518 direct clutch snap ring in place of the stock intermediate clutch snap ring (they are selective and come in thicknesses ranging from .068-.120 or so)
- Internally Dual feeding the direct clutch is up to you but if HP/TQ is under 450 its not necesssary.
- Optional unless hp=> 500-550 and street strip/high rpm: Billet rollerized forward hub
- DO NOT INSTALL A TRANSGO HD2 kit
- DO NOT INSTALL ANY "PRESSURE RELIEF mechanism made by Transgo or anyone else
Ill edit to add if i think of anything else.
Reply back with any ?s