Replace F5M33 Tranny with a F5M31 - Can I?

[Bymp]

I have a 97 Spyder GST that the transmission died in.

I can get a spare F5M31 transmission from a friend. My question is.... Can I use this transmission in my car?

I've been told the F5M31 transmission is not as strong as the F5M33, this isn't a problem at the moment since my car is still stock.

As far as bolt off, bolt on, will I run into any problems?

Please advise,

Joe

 

[bradselph]

You can use it 100% just drop the old one and pop the new one in,

You will notice a bit more low end as the gearing is a bit different i pushed about 300 ft lbs of torque on my f5m31 for about a year never had a problem.

 

[Bymp]

Thank you very much,

That clears my mind a lot.

 

[19Eclipse90]

You'll need the axles as well.

 

[m_0ney_pit]

yea you need the axles from a 4g64 spyder if you go with the 31, the input shafts are smaller than on the 33 transmission

 

[pauleyman]

Clutch is different also. NT doesn't use the stepped flywheel or clutch.

 

[19Eclipse90]

True, but the F5M31 can use the turbo clutch and flywheel.

 

[m_0ney_pit]

Clutch is different also. NT doesn't use the stepped flywheel or clutch.

no one is talking about a 420a nt here. The 31 transmission he would use comes from galant or nt spyder and they both use a stepped flywheel. which accept the turbo clutch. The 4g64 flywheel is actually an upgrade over the stock 4g63t flywheel because its lighter.

 

[bastarddsm]

Isn't a F5M31 a trypical n/t trans? So wouldn't a F5M31 with 2g style mounts not exist?

 

[m_0ney_pit]

Isn't a F5M31 a trypical n/t trans? So wouldn't a F5M31 with 2g style mounts not exist?

nah its what comes in the manual 4g64 powder 2g spyder and 7/8g galant. The 420a 2g uses the f5mc1.

 

[bryanwheat]

I recently did this swap on a 2g turbo car. The flywheel is stepped like the turbo flywheel but it is slightly different where pressure plate bolts to the flywheel. The spyder flywheel is more rounded on the and the turbo flywheel is flat on the side. The pressure plate and disc are interchangeable between the 2 flywheels, but if you use the turbo flywheel than you will have to do a small amount of grinding inside the bellhousing or else the flywheel will bind up. There is a spot by the starter where the casting sticks out a bit, just take a die grinder and flatten it out a little bit and it will be fine.

 

[m_0ney_pit]

I recently did this swap on a 2g turbo car. The flywheel is stepped like the turbo flywheel but it is slightly different where pressure plate bolts to the flywheel. The spyder flywheel is more rounded on the and the turbo flywheel is flat on the side. The pressure plate and disc are interchangeable between the 2 flywheels, but if you use the turbo flywheel than you will have to do a small amount of grinding inside the bellhousing or else the flywheel will bind up. There is a spot by the starter where the casting sticks out a bit, just take a die grinder and flatten it out a little bit and it will be fine.

Really you have to grind, do you have a picture of the spot? The f5m33 uses the f5m31 bell housing!

 

[bryanwheat]

Really you have to grind, do you have a picture of the spot? The f5m33 uses the f5m31 bell housing!

I don't have a picture, but as i said i just did this like a month ago and the flywheel would catch on the raised spot in the bellhousing before i ground the stop off. It took like 2 minutes to grind it enough for it to not rub any more.

 

[Circuit18]

I'm in the reverse I swapped a f5m31 to f5m33 have axles in. Is cable different? Is clutch assembly different? Auto parts said its same. Clutch doesn't seam to disengage.