4L80e aluminum direct piston
Thread Starter
Joined: Nov 2013
Posts: 6,389
Likes: 558
From: Portlandia
4L80e aluminum direct piston is there a general consensus of when a th400 cast aluminum direct piston is a must have?
I recently tore down the transmission from my turbo work truck and it ended up being in great shape other than extremely worn turbine splines on the input shaft.
it was built pretty mildly. dual feed, 3-4 accumulator delete, sonnax LB1 pressure regulator kit, green borgs. clutches set up on the tight side ~.007 per friction or so. stock separator plate orifice sizes. molded type pistons seemed to do quite well.
fuel consumption on e85 would put it in the 600 wheel hp range, 4000lb truck.
it's religiously overloaded with firewood, lathes mills etc
just curious if I'm putting aluminum direct pistons in for extra cost to the customer with no gains.
I recently tore down the transmission from my turbo work truck and it ended up being in great shape other than extremely worn turbine splines on the input shaft.
it was built pretty mildly. dual feed, 3-4 accumulator delete, sonnax LB1 pressure regulator kit, green borgs. clutches set up on the tight side ~.007 per friction or so. stock separator plate orifice sizes. molded type pistons seemed to do quite well.
fuel consumption on e85 would put it in the 600 wheel hp range, 4000lb truck.
it's religiously overloaded with firewood, lathes mills etc
just curious if I'm putting aluminum direct pistons in for extra cost to the customer with no gains.
TECH Junkie
Joined: Jun 2008
Posts: 3,202
Likes: 1,390
From: Nitro Alley
There is absolutely nothing wrong with the 1997+ OEM "Bonded Steel" Direct Piston.
The only reason to really use a THM400 "Wide Work-Surface Area" Aluminum Direct Piston...
Is to increase the Clutch Pack clearance for thicker steel plates/ additional friction plates.
The only reason to really use a THM400 "Wide Work-Surface Area" Aluminum Direct Piston...
Is to increase the Clutch Pack clearance for thicker steel plates/ additional friction plates.
