All I see is auto to manual swaps, I would rather have an auto in my rig. How direct is the swap? Its a 87 d150 with the slant 6 and 4 speed. I have an old junk slant 6 and 904 I pulled out of my dart sport the trans had reverse out but I have some good donor parts there and will use that as a core or find another. Will I need a different length driveshaft?
87 d150 4 speed to 904 trans swap
- Thread starter Dill
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Ironracer
Gearhead
If I recall correctly, the 727 and a-833 share a common length. It's almost 4" between a 904 and 727 DS length in a passenger car
Badvert65
Long Time Mopar Nut
One other thing, the output shaft on a 904 is different (smaller) than a 727.
jus sayin....
jus sayin....
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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As far as swaps go this is an easy one.
But, IMO; this will not end well.
If you currently have a NP435, the gears in that unit, together with the right rear gear, provide pretty good slanty "performance".
But with the switch to an automatic, you will lose that 4-gear spread, and are limited by the stall at zero mph. So unless you carefully co-ordinate the stall-rpm and gears, you may end up with a turd combo, that will require more money to rectify.
The only transmissions that might be able to share the same driveshafts, are
Combo#1; the short-tail A833 from behind a Slanty, and any A904. or
Combo#2, the long tail A833 and any A727.
The NP435 is a unit unto itself. It usually has a deep low gear that is un-synchronized, and a top-mounted shifter that is pretty long. The rear often has a parking brake on it and it usually has a 2-piece driveshaft with a center hanger-bearing.
IMO,
for a city-truck; swapping from a Slanty/manual to a slanty/904 is probably gonna work reasonably well. But
For a slanty that has to haul on the hiway @ 65=2400rpm or less, no; you will be better off with a 318.
Hilly terrain will only make it worse.
And towing will probably require a bigger rear gear than you currently have.
The slanty/904 will likely/surely, suck more gas.
Tall tires, with hiway gears, will kill performance.
But, IMO; this will not end well.
If you currently have a NP435, the gears in that unit, together with the right rear gear, provide pretty good slanty "performance".
But with the switch to an automatic, you will lose that 4-gear spread, and are limited by the stall at zero mph. So unless you carefully co-ordinate the stall-rpm and gears, you may end up with a turd combo, that will require more money to rectify.
The only transmissions that might be able to share the same driveshafts, are
Combo#1; the short-tail A833 from behind a Slanty, and any A904. or
Combo#2, the long tail A833 and any A727.
The NP435 is a unit unto itself. It usually has a deep low gear that is un-synchronized, and a top-mounted shifter that is pretty long. The rear often has a parking brake on it and it usually has a 2-piece driveshaft with a center hanger-bearing.
IMO,
for a city-truck; swapping from a Slanty/manual to a slanty/904 is probably gonna work reasonably well. But
For a slanty that has to haul on the hiway @ 65=2400rpm or less, no; you will be better off with a 318.
Hilly terrain will only make it worse.
And towing will probably require a bigger rear gear than you currently have.
The slanty/904 will likely/surely, suck more gas.
Tall tires, with hiway gears, will kill performance.
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