I'm putting big axles and tires on my rig and I was considering going to an american auto trans and Atlas. Do I have any options if I want to keep the 3f?
Auto trans options
- Thread starter SHO NUFF
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Check out marks4wd.com or advanceadapters.com
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- #3
Has anyone put a 700r or TH400 behind a 3fe?
Th400 would be overkill for a 3FE. It is a heavy duty application trans that sucks 15% of the horsepower just to make it go. It would not get you any better gearing than stock.
A 3FE would be better served by a TH700R4 or the at least equally capable, but not as well geared A440. With the 700 you'd get OD and a low first, but damn the 440 is a good trans. It's expensive to fix, but it'd be expensive to put in a lesser tranny as well.
Either the 400 or the 700 is going to give you driveshaft clearance issues because of the wide pans.
'course you could buy my TH350 and not have clearance issues.
A 3FE would be better served by a TH700R4 or the at least equally capable, but not as well geared A440. With the 700 you'd get OD and a low first, but damn the 440 is a good trans. It's expensive to fix, but it'd be expensive to put in a lesser tranny as well.
Either the 400 or the 700 is going to give you driveshaft clearance issues because of the wide pans.
'course you could buy my TH350 and not have clearance issues.
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- #5
What do I have to do to get a 700 to bolt up to my 3f?
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Anybody?SHO NUFF said:
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- #9
Thanks guys. I found one.
Gumby, the A440 isn't exactly an efficient auto trans either. 15% driveline loss would be considered efficient even for a manual. Those of us with auto's are probably loosing even more.
DBS311 said:
Dunno about the A440, but here is a study done by TCI I found comparing autos. THe TH400 isn' the worst, but ain't great.
Here are results of a test executed by TCI in July 1991 to find HP losses through a transmission:
Transmission - HP Loss
Powerglide - 18
TH350 - 36
TH400 - 44
Ford C6 - 55-60
Ford C4 - 28
Chrysler A904 - 25
Chrylser 727 - 45
The weight of the cast iron forward and direct drums and the power to get them turning is said to make a difference with the TH400
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- #13
3f to 700. up n over is going to make one for me. They haven't got back to me with the cost.azaussie said:
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- #16
They never got back to me and I haven't called. My project is on hold for now anyway. I'm in the process of buying a house.