What tranny

[Aussie67]

I have a 73 Q code making about 300hp at the rear wheels with an FMX that appears to be on the way out. Fluid leaking from the breather while sitting - suspect torque converter seal and the transmission is neutralising when cold so looks as though rebuild / replacement is in my near future.

Would love to hear from y'all what I should replace it with and best place to source a replacement. Rebuilding is an option I guess.

Have been thinking about AOD, but not sure? I live in the city now and will not do that much highway driving with this car.

Please share your thoughts / advice.

 

[piper62j]

A C6 will get you around ok, and B&M produces beefed up parts for them which will increase performance.. You can also buy a complete B&M crate transmission & torque converter which will bolt up..

 

[CZ-75]

Biggest question is auto or stick?

If you want auto, definately go with something with overdrive. Then, it's a question of AOD versus 4R70W. AOD uses throttle cable, 4R70W uses electronic computer, which Bauman offers.

I went with a wide ratio AOD, but if I had to do it again, I probably would have opted for the 4R70W due to being able to control shift points. Th ewide ratio AOD uses the gear set from the 4R70W. The 4R70W is "wide ratio," meaning it has a more agressive first gear, but still has an overdrive.

So, you will have a more agressive first gear, and lower RPMs at highway cruising speeds.

 

[Aussie67]

Biggest question is auto or stick?

If you want auto, definately go with something with overdrive. Then, it's a question of AOD versus 4R70W. AOD uses throttle cable, 4R70W uses electronic computer, which Bauman offers.

I went with a wide ratio AOD, but if I had to do it again, I probably would have opted for the 4R70W due to being able to control shift points. Th ewide ratio AOD uses the gear set from the 4R70W. The 4R70W is "wide ratio," meaning it has a more agressive first gear, but still has an overdrive.

So, you will have a more agressive first gear, and lower RPMs at highway cruising speeds.

Thanks for those thoughts. I will definitely stay with automatic..

 

[Don C]

The C6 can easily handle your power, but it is not a very efficient transmission, and looses more due to lack of lock-up torque converter and OD. With your rear wheel HP I would want a built up AOD or 4R70W. My preference is the 4R70W, which I plan on replacing my C6 with.

 

[lduke12]

The C6 can easily handle your power, but it is not a very efficient transmission, and looses more due to lack of lock-up torque converter and OD. With your rear wheel HP I would want a built up AOD or 4R70W. My preference is the 4R70W, which I plan on replacing my C6 with.

Anyone ever mated a 4R70W to a 429 BBF? Seems like all the adapter plates out there are made only for AOD.

 

[Luke]

If you don't need OD then I would go C4 light relatively cheap,easy to get parts for here.and it will easily handle your hp or future up grades in hp. Try a place called Craig's autos in NSW (02) 97551158 disregard RVO trannies, rang a mate to check lets say he ain't anybody's first choice any more.

My 2 bits worth

 

[Don C]

Anyone ever mated a 4R70W to a 429 BBF? Seems like all the adapter plates out there are made only for AOD.

Because the AOD-E/4R70W (with small block bellhousing bolt pattern and not Mod bolt pattern) is a direct replacement for the AOD, using the same flexplate and bolt patterns, an AOD adapter should work with a 385 series engine.

 

[cudak888]

Anyone ever mated a 4R70W to a 429 BBF? Seems like all the adapter plates out there are made only for AOD.

If going for a non-stock appearance, why not put a E40D behind the 429, and enlarge the transmission tunnel as needed?

-Kurt

 

[lduke12]

Anyone ever mated a 4R70W to a 429 BBF? Seems like all the adapter plates out there are made only for AOD.

If going for a non-stock appearance, why not put a E40D behind the 429, and enlarge the transmission tunnel as needed?

-Kurt

More work than i wanted to do. I have the original C6 that came with the 429, but i don't know if i want to spend 2800 for a Gear Vendors. The 429 is a stroker motor stroked out to 521 cubes with a build meant to be a torque monster. Engine is pretty much almost ready to be swapped in, just need to figure out the rest of the drivetrain. Just wanted something that fit right in and didn't break the bank.

 

[cudak888]

More work than i wanted to do. I have the original C6 that came with the 429, but i don't know if i want to spend 2800 for a Gear Vendors. The 429 is a stroker motor stroked out to 521 cubes with a build meant to be a torque monster. Engine is pretty much almost ready to be swapped in, just need to figure out the rest of the drivetrain. Just wanted something that fit right in and didn't break the bank.

I just ran across a thread on TheLincolnForum.net where the E4OD was being discussed for 460's, and the possibility of trans tunnel clearance issues. If it doesn't fit in one of the Lincolns, it'll never fit comfortably in our cars.

-Kurt

 

[Mesozoic]

The E4OD is a good option for those with the big block bellhousing. There's a lot of parts out there to improve their performance as well, but it's really an evolved C6 with OD. The dimensions will be very similar to that of a C6.

 

[cudak888]

The E4OD is a good option for those with the big block bellhousing. There's a lot of parts out there to improve their performance as well, but it's really an evolved C6 with OD. The dimensions will be very similar to that of a C6.

Reality check: This is a BBF C6 next to a E4OD:

And we think the C6 is a behemoth.

-Kurt

 

[Mesozoic]

LOL That looks massive next to the C6. It's supposed to have started its evolutionary path from the C6, just as the AOD and 4R70W have evolved from the C4 light duty transmissions... I had no idea the E4OD was that large, however. I just read that the trans is 8" longer than a C6, but the bellhousing area has to be close to a C6 because it's the same block pattern, right?

 

[cudak888]

LOL That looks massive next to the C6. It's supposed to have started its evolutionary path from the C6, just as the AOD and 4R70W have evolved from the C4 light duty transmissions... I had no idea the E4OD was that large, however. I just read that the trans is 8" longer than a C6, but the bellhousing area has to be close to a C6 because it's the same block pattern, right?

Bellhousing pattern on the E4OD is the standard BBF/385 series pattern and should bolt straight up. The C6 in the photo has the larger-flange case as well.

It's 4" longer than the C6 though, not 8".

Frankly, I think it'd be a much better experiment to see if the E4OD would fit in the transmission tunnel of an old Lincoln before a Mustang. Contrary to the hubbub on TheLincolnForum.net, I think the trans tunnel may be large enough on the Mark IV, V, and 1970-1979 Continentals to accept the E4OD, and that any modifications needed would be minor.

On the other hand, I doubt if the wide center section will clear the taper on our cars, and enlarging the tunnel may require using seats other than stock - or using the taller coupe seat platforms on Sportsroofs to get the seats away from the tunnel.

-Kurt

 

[Aussie67]

If you don't need OD then I would go C4 light relatively cheap,easy to get parts for here.and it will easily handle your hp or future up grades in hp. Try a place called Craig's autos in NSW (02) 97551158 disregard RVO trannies, rang a mate to check lets say he ain't anybody's first choice any more.

My 2 bits worth

Thanks Luke. OD is really not a big issue for me, nice to have maybe but like I said my driving will mainly be around Perth anyway.

I was thinking C4 initially, I might give Craig's a try.

 

[mus72]

Why change , would be much simpler to rebuild the fmx which is capable of handling 450hp in stock form a c4 would need upgraded to handle that .Also the fmx is much lower in parasitic loss than a c6.

Rockauto do rebuild kits for them cheap , bad shoe do rebuild dvd's then add a shift kit , it would save changing torque convertor,prop shaft and messing about with linkages .

 

[Mesozoic]

I don't know, once you've driven a vehicle with OD it's tough to accept not having it.

 

[turtle5353]

Why change , would be much simpler to rebuild the fmx which is capable of handling 450hp in stock form a c4 would need upgraded to handle that .Also the fmx is much lower in parasitic loss than a c6.

Rockauto do rebuild kits for them cheap , bad shoe do rebuild dvd's then add a shift kit , it would save changing torque convertor,prop shaft and messing about with linkages .

I have a c4 in my mach1 and have had no issues with it yet. I ran 400+hp. through it for about 5 years and I have been running 550+hp through it now for about a year with the new motor. It has a built valve body, 3000 stall converter and upgraded clutches but that's it. Tough little bastard, but it probably helps that I never can get the car to hook up under 45mph.