turbo 400
11-05-2006, 04:13 PM
#1
turbo 400
well my tranny is makin some noises and clunks again, skippin from 4th and 3rd sometimes. my locker is in and Im pissed cuz I cant drive it 
so im lookim at new options, if I were to dd something else is the 400 worth it? if so where to look for one, what parts? and how streetable are they really? basically like just drivin my truck in 3 all the time?
so im lookim at new options, if I were to dd something else is the 400 worth it? if so where to look for one, what parts? and how streetable are they really? basically like just drivin my truck in 3 all the time?
11-05-2006, 08:49 PM
#5
TH400 is a very strong transmission but you cannot control it electronicly. Shift points have to be determined by how you weight the governor, and line pressure is mechanical too. If you don't like how the shift firmnesses comes out you'll have to drop the valve body and mod the separator plate. It's also difficult to get them to be very soft and mild at low TPS but firm and quick WOT at the same time.
The 4L80-E uses some of the exact same geartrain at the TH400 - even the clutches are interchangable. With the 4L80-E you get Overdrive through a third planetary for FOUR TRUE speeds instead of the 2-planetary POS 4L60-E. It's fully electronic, has input and output RPM sensors for adaptive shift control, it has a lock-up converter, and several vendors provide everything you need to do the swap. The 4L80-E makes every forward shift by engaging a real clutch pack, no bands are used to shift like in the 4L60-E. (disc-clutch packs versus bands in an automatic transmission are as different and superior as disc versus drum brakes.)
Some people complain about the gear ratio range in the 4L80-E. Just imagine how much worse it would be without overdrive. Go for the 4L80-E.
The 4L80-E uses some of the exact same geartrain at the TH400 - even the clutches are interchangable. With the 4L80-E you get Overdrive through a third planetary for FOUR TRUE speeds instead of the 2-planetary POS 4L60-E. It's fully electronic, has input and output RPM sensors for adaptive shift control, it has a lock-up converter, and several vendors provide everything you need to do the swap. The 4L80-E makes every forward shift by engaging a real clutch pack, no bands are used to shift like in the 4L60-E. (disc-clutch packs versus bands in an automatic transmission are as different and superior as disc versus drum brakes.)
Some people complain about the gear ratio range in the 4L80-E. Just imagine how much worse it would be without overdrive. Go for the 4L80-E.
11-06-2006, 06:16 AM
#6
TECH Fanatic
iTrader: (65)
Join Date: Jun 2006
Location: Tyndall AFB / Panama City, FL
Posts: 1,187
Likes: 0
Received 0 Likes
on
0 Posts
yeah i had thought about doing this also mostly to be more cost effective. But i decided in the long run it would be much better to keep overdrive and electronic control with the 4l80e instead.
I actually drove around for a while in 3rd to see what it was like and i could'nt stand it, but then again i've got a 4.59 final gear ratio.
I actually drove around for a while in 3rd to see what it was like and i could'nt stand it, but then again i've got a 4.59 final gear ratio.
