Nv3500 vs ax15

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DumpsterFire

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My floor is rotten and I want a 5 speed. I know neither is gonna fit into my 64 dart but I'm ready to cut the tunnel out and make it fit. It's going a behind a 360 magnum but this is just a very stock street car so I'm sure I'll be fine. These two trannys are cheap and everywhere in old dakotas. Any ideas on which one to go with. How substantial is the size difference?
 
I think you'd be happier with the gear spacings on the AX-15. The NV 3500 is going to have the gear splits only a truck could love.
 
on the NV you'll need one with the speedo hook up, if you care about that sort of thing.
don't be lulled by the siren song of the ram version, the shifter is in a different place and makes that tricky.

the trans mount is probably going to be the biggest obstacle.

the gear splits are booty unless you've got gobs of torque. if you soft pedal it, you'll likely be fine. they weren't excact robust units.

you could probably do a T5 for about the same money and it'd be a lot easier.
 
I think you'd be happier with the gear spacings on the AX-15. The NV 3500 is going to have the gear splits only a truck could love.
I drive a dakota with an ax15 and really like it but I was worried about killing it with a 360
 
on the NV you'll need one with the speedo hook up, if you care about that sort of thing.
don't be lulled by the siren song of the ram version, the shifter is in a different place and makes that tricky.

the trans mount is probably going to be the biggest obstacle.

the gear splits are booty unless you've got gobs of torque. if you soft pedal it, you'll likely be fine. they weren't excact robust units.

you could probably do a T5 for about the same money and it'd be a lot easier.
I'm planning to tie the subframes together and just put a cross member wherever the trans wants it
 
on the NV you'll need one with the speedo hook up, if you care about that sort of thing.
don't be lulled by the siren song of the ram version, the shifter is in a different place and makes that tricky.

the trans mount is probably going to be the biggest obstacle.

the gear splits are booty unless you've got gobs of torque. if you soft pedal it, you'll likely be fine. they weren't excact robust units.

you could probably do a T5 for about the same money and it'd be a lot easier.
When I was looking at somthing like a t5 out of a s10 it didn't seem to be any more beefy
 
I'm planning to tie the subframes together and just put a cross member wherever the trans wants it
keep in mind that the stock transmission x-member and hoop are an integral part of the "frame" and because the t-bars anchor there it is critical to retain the structure and if modified to substantially beef it up.

When I was looking at somthing like a t5 out of a s10 it didn't seem to be any more beefy
i only say T5 because the road has been traveled before and the parts are there. they're rated about the same torque wise. but you're in a light car and you'll have limited tire width-- unless you mini tub out back.

there's somebody on here running an ax15... i forget who but it's seemed to hold up thus far
 
keep in mind that the stock transmission x-member and hoop are an integral part of the "frame" and because the t-bars anchor there it is critical to retain the structure and if modified to substantially beef it up.


i only say T5 because the road has been traveled before and the parts are there. they're rated about the same torque wise. but you're in a light car and you'll have limited tire width-- unless you mini tub out back.

there's somebody on here running an ax15... i forget who but it's seemed to hold up thus far
Yeah I ain't taking the cross member for the stock tranny out with out replacing it with a cross member. If it fits I'll just leave it
 
Yeah I ain't taking the cross member for the stock tranny out with out replacing it with a cross member. If it fits I'll just leave it
remember, it's also the hoop above it that attaches to the floor that also provides substantial support.
 
keep in mind that the stock transmission x-member and hoop are an integral part of the "frame" and because the t-bars anchor there it is critical to retain the structure and if modified to substantially beef it up.


i only say T5 because the road has been traveled before and the parts are there. they're rated about the same torque wise. but you're in a light car and you'll have limited tire width-- unless you mini tub out back.

there's somebody on here running an ax15... i forget who but it's seemed to hold up thus far
The ax15 is so plug and play is why I'm drawn to it and I like how it feels so the using it every day bias is there
 
AX-15; * 3.83-2.33-1.44-1.00-.79od splits of; .61-.620-.690-.79
NV/Dak; 3.49-2.14-1.38-1.00-.73od splits of; .61-.645-.725-.73
The Dak is pretty tall for your Dart, the belly may get to dragging on the ground.

I like the AX and if I was younger, I would put one behind a peppy hi-compression 318
 
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keep in mind that the stock transmission x-member and hoop are an integral part of the "frame" and because the t-bars anchor there it is critical to retain the structure and if modified to substantially beef it up.


i only say T5 because the road has been traveled before and the parts are there. they're rated about the same torque wise. but you're in a light car and you'll have limited tire width-- unless you mini tub out back.

there's somebody on here running an ax15... i forget who but it's seemed to hold up thus far
Ain't gonna tub it out as long as folks at work don't bully me into it
 
@dartslantsix and @75slant6 are/were running an Ax15. Dartslantsix had his for sale several months ago.

Either way, they should both have some idea of how they work in a car.

Also, the AX15 and R154 have the same bellhousing bolt pattern. As does the AR5/MA5. So you could start with an AX15 and then move to something more "car-like" if you wanted. Only caveat is the R154 seemed to have gotten pretty expensive over time.
 
My nv3500 in my 03 Dakota behind a 239 v6 has been trouble free for 400,000 miles other than changing the clutch. Not sure what you would do for a speedo though
 
I’ve put 20k trouble free miles on the ax15 in my Duster. Granted, it’s currently behind a bone stock 5.9 magnum.
 
T5 out of an early S10 is not good enough

you need a world class unit really and one with quite a long input
and a good supply of 9.5 10 or 10.5 inch clutch plates

T5 out of a 2000-2004 mustang might be robust enough (long toploader type input)
Z spec racing T5 might be (short toploader type input)
V8 mustang T5 might be (some long some short)

the only bit of S10 T5 you need for a truck or bench seat install is the tail housing and shifter.

couple of caveats

late model world class S10 T5 tail uses an electronic speedo but will probably fit the mustang T5, both are world class. The electronic pickup will be in the wrong place so you'd need to come up with a way of mounting your chosen reluctor at the new spot on the output shaft..

early model s10 tail needs work to fit the tail housing onto the late model worldclass mustang t5
it has a mechanical speedo hole. it is in the wrong place for a mustang output shaft, so you need a kit or some ingenuity to use a split collar and some shims and a modified chevy speedo gear to match with the chevy bullet speedo drive you need to use at a place on the output shaft that was not designed to have the drive gear mounted on it.
the housing needs the scroll pattern at the end of the 5th gear area to be machined flat, level with the lowest profile to convert the housing from none world class to world class.
If the Mustang Trans is the type with 1) a Bolt 2) a reverse light switch and 3) some strange metal stud in the drivers side. Then the end of the 5th/reverse rod is too long for the pocket in the earlier none world class tail housing, swap for earlier rod and spring or cut/grind off, just enough, of the end in order to get into reverse. re counter sink the oil hole in its end and leave enough of the fat end of it, to keep it aligned. if there are only two things bolted into the side of the trans case no weird pressed in dark metal stud (supports the later spring/revers/fifth rod) you are ok

if the 5th reverse brake has a tab sticking out of its retainer use a flat milling bit to make a hole of 1-2 mm deep at the top of the scroll section behind the retainer on the back of 5th to trap that tab and stop the retainer spinning so it acts as a synchro/brake for going into reverse.
or snap/grind the tap off and just make sure you pause in neutral before going into reverse like you had to with all T5s before 2000 and all since about 2005.
this Tab/brake thing was not continued as it never worked very well.

pictures here https://www.jalopyjournal.com/forum/threads/t5-transmission-s10-tail-extension.1247081/

the s10 housing will put the shifter box just in front of the deep part of the cross member in the tunnel if you use a mopar bell and a 3/4 inch adapter. Using a thinner 1/4 inch steel adapter leads to easier fit and less trimming of the front of the cross member becase the trans and shifter are 1/4 to 1/2 inch further forward. i.e you just cut single skinned floor tunnel not the double skin at the edge of the cross member. basically to fit you will need to trim off the front upper most edge of the cross member but not the main Meat of it. as it were.

On a small tunnel car the drivers side of the box upper edge will hit the tunnel. air hammer the tunnel or cut to fit. this is a problem on 60s auto floor pan but not on duster floor pan

i got this far but then chickened out on a car that cost me 11K and is now worth 6-8 x that...
yes i'm a chicken.... i stuck my Australian Borgwarner single rail back in (like a ford SROD but smaller and with sensible ratios and a dip in the shift rail for the cross member) this is the Aussie small block 4 speed used my ford chrysler and leyland downunder no 833 for them....

you will need the chevy mount not the mustang one the chevy mount goes on with m10 1.5 bolts on an S10 housing/mount/platform
 
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Here's what it took to fit the AX15 in my Barracuda: Rebuilding the Transmission Tunnel
It shifted smooth with synthetic oil in it. I also shortened up the shifter. I was running a 5.2L Magnum.
Only thing I didn't like was the gear spacing. I have 3.73s in the rear. First gear was pretty much a granny. When racing, I'd start out in 2nd. Probably would be better with higher gears in the rear end.
You can run a mechanical speedo with it.
My friend said AX15s are plenty strong. He's into Jeeps and he told me there's guys running them behind healthy V8s with giant tires. BUT, I could never find a torque rating for them.
I'm swapping to a hemi now and have decided to go with the TKX.
 
Here's what it took to fit the AX15 in my Barracuda: Rebuilding the Transmission Tunnel
It shifted smooth with synthetic oil in it. I also shortened up the shifter. I was running a 5.2L Magnum.
Only thing I didn't like was the gear spacing. I have 3.73s in the rear. First gear was pretty much a granny. When racing, I'd start out in 2nd. Probably would be better with higher gears in the rear end.
You can run a mechanical speedo with it.
My friend said AX15s are plenty strong. He's into Jeeps and he told me there's guys running them behind healthy V8s with giant tires. BUT, I could never find a torque rating for them.
I'm swapping to a hemi now and have decided to go with the TKX.
Higher gears are definitely required with the ax15. I was running 3.23’s in my Duster and still only using 1st gear if I was taking off on a hill. I’ve since installed 2.76’s and now use 1st through 5th gears as intended.
 
Higher gears are definitely required with the ax15. I was running 3.23’s in my Duster and still only using 1st gear if I was taking off on a hill. I’ve since installed 2.76’s and now use 1st through 5th gears as intended.
Wow. What must the final drive ratio be in fifth? 1.8 to 1? Usefully at all under 85 mph?
 
Wow. What must the final drive ratio be in fifth? 1.8 to 1? Usefully at all under 85 mph?
Here’s the rpm/mph difference between the 3.23’s and 2.76’s in 5th gear. I typically use 5th any I’m going 55+

IMG_7393.jpeg
 
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