FMX trani “toast”

swice · Oct 31, 2024

Hey awesome group, my Fmx trani went out, ‘73 vert 351c, wouldn’t shift into high, took it in, only local trani shop simply said parts not available, etc, wanted to go with later model 4 speed for twice what seemed reasonable.
So, anyone know where I could get rebuilt FMX? I’m not mechanically inclined enough myself to rebuild at home. Would like to keep original, any ideas most appreciated, many thanks, john

Sheriff41 · Oct 31, 2024

Rebuild kits for FMXs are readily available. Check with some of the reputable independent mechanics in your area and see if any will take it on. The FMX are not difficult to overhaul so I'm surprised they turned you away.

swice · Oct 31, 2024

Sheriff41 said:
Rebuild kits for FMXs are readily available. Check with some of the reputable independent mechanics in your area and see if any will take it on. The FMX are not difficult to overhaul so I'm surprised they turned you away.

Thanks, pretty limited in my area, I’ll keep pushing. A mechanic I trust just said they wouldn’t trust the rebuild for some reason, I suspected they just didn’t want to do it.

turtle5353 · Oct 31, 2024

Where you located?

swice · Oct 31, 2024

turtle5353 said:
Where you located?

Fort Smith, Arkansas

giantpune · Oct 31, 2024

There are lots of shops in my AO that will rebuild an FMX. Even if there weren't, you can pretty easily swap in a C4 or C6 in its place, which are also very easy to come by. If you have the tools, you will save a grand and open your options for a shop up if you pull the transmission yourself. Yank it out, toss it in the back of a truck. Surely you can find a ship within an hour drive that will rebuild it. Then put it back in your car.

As far as swapping to something else, a C4 or C6 would be the cheapest transmission swap. Followed by some overdrive automatic one. A manual swap will be more expensive due to there being a lot more parts that get swapped in like adding a clutch pedal, flywheel, master and slave cylinders, and shifter. All in, parts to convert an automatic to a manual start around $4k including tax and shipping. Its a couple days worth of labor.

swice · Oct 31, 2024

giantpune said:
There are lots of shops in my AO that will rebuild an FMX. Even if there weren't, you can pretty easily swap in a C4 or C6 in its place, which are also very easy to come by. If you have the tools, you will save a grand and open your options for a shop up if you pull the transmission yourself. Yank it out, toss it in the back of a truck. Surely you can find a ship within an hour drive that will rebuild it. Then put it back in your car.

As far as swapping to something else, a C4 or C6 would be the cheapest transmission swap. Followed by some overdrive automatic one. A manual swap will be more expensive due to there being a lot more parts that get swapped in like adding a clutch pedal, flywheel, master and slave cylinders, and shifter. All in, parts to convert an automatic to a manual start around $4k including tax and shipping. Its a couple days worth of labor.

Great advice, I’ll do some checking, thank you!

swice · Oct 31, 2024

Hey everyone, I found a C6 rebuilt 3 year 100k warranty. I appreciate everyone’s help. Best to all, John

giantpune · Oct 31, 2024

swice said:
Hey everyone, I found a C6 rebuilt 3 year 100k warranty. I appreciate everyone’s help. Best to all, John

Good deal. Before you get too gung ho, make sure you know what all will need to change. Like i think the transmission lines are different, and C6 ones will run $70 a set.

The neutral safety switch is a bit different. The FMX cars should have it in the shifter, while the C6 cars had it on the side of the transmission. I believe you can get away with leaving yours in the shifter and it'll still work fine.

The crossmember is a little different. You may be able to make your existing one work.

I'm not certain how different the linkage rods are for the shifting and the kickdown. That may be an ebay item.

The length of the driveshaft may also need to be different. Its cheaper to shorten one up than to buy a longer one.

73pony · Oct 31, 2024

I have a good FMX out of a 73 351C coupe just sitting. Pulled it when I upgraded to a T5. Trans has about 68K miles on it. You can have it free. I'm in Iowa. You come pick up or cover shipping.

swice · Oct 31, 2024

giantpune said:
Good deal. Before you get too gung ho, make sure you know what all will need to change. Like i think the transmission lines are different, and C6 ones will run $70 a set.

The neutral safety switch is a bit different. The FMX cars should have it in the shifter, while the C6 cars had it on the side of the transmission. I believe you can get away with leaving yours in the shifter and it'll still work fine.

The crossmember is a little different. You may be able to make your existing one work.

I'm not certain how different the linkage rods are for the shifting and the kickdown. That may be an ebay item.

The length of the driveshaft may also need to be different. Its cheaper to shorten one up than to buy a longer one.

Awesome advice, will pass on to the shop, many thanks!

swice · Nov 1, 2024

73pony said:
I have a good FMX out of a 73 351C coupe just sitting. Pulled it when I upgraded to a T5. Trans has about 68K miles on it. You can have it free. I'm in Iowa. You come pick up or cover shipping.

Wow, let me see if I can undo my purchase, many kind thanks!

swice · Nov 1, 2024

swice said:
Wow, let me see if I can undo my purchase, many kind thanks!

Ok!! I will gladly pay shipping, could you email me at [email protected] for arrangements, I have the shop it needs to be sent to. I have a FedEx number, though any shipper I will credit card the amount.

I would like to pay you for your trouble, this keeps the vert original, which I really wanted. It’s my dd as well. I can’t thank you enough, John

swice · Nov 1, 2024

73pony said:
I have a good FMX out of a 73 351C coupe just sitting. Pulled it when I upgraded to a T5. Trans has about 68K miles on it. You can have it free. I'm in Iowa. You come pick up or cover shipping.

Ok!! I will gladly pay shipping, could you email me at [email protected] for arrangements, I have the shop it needs to be sent to. I have a FedEx number, though any shipper I will credit card the amount.

I would like to pay you for your trouble, this keeps the vert original, which I really wanted. It’s my dd as well. I can’t thank you enough, John

Quote

73pony · Nov 1, 2024

Email sent

transmissionguy · Nov 1, 2024

swice said:
Hey awesome group, my Fmx trani went out, ‘73 vert 351c, wouldn’t shift into high, took it in, only local trani shop simply said parts not available, etc, wanted to go with later model 4 speed for twice what seemed reasonable.
So, anyone know where I could get rebuilt FMX? I’m not mechanically inclined enough myself to rebuild at home. Would like to keep original, any ideas most appreciated, many thanks, john

Does your FMX have a strong reverse? If so you probable do not need a rebuild. Problems with the vacuum modulator, detent lever (kickdown) or a problem with the release circuit of the intermediate (2nd or front) band servo will cause delayed or no shift into 3rd. To shift from 2nd to 3rd the FMX requires intermediate band release and direct clutch apply. (forward and direct clutch are on for high gear. Direct clutch and rear band are on for reverse.) If you have good (not slipping) forward and reverse your problem in likely minor. Check vacuum modulator and vacuum supply, check detent lever and valve for being stuck at WOT. I have also seen a small steel plug blow out of place in the front servo causing no shift to high. Good luck!

giantpune · Nov 1, 2024

transmissionguy said:
Does your FMX have a strong reverse? If so you probable do not need a rebuild. Problems with the vacuum modulator, detent lever (kickdown) or a problem with the release circuit of the intermediate (2nd or front) band servo will cause delayed or no shift into 3rd. To shift from 2nd to 3rd the FMX requires intermediate band release and direct clutch apply. (forward and direct clutch are on for high gear. Direct clutch and rear band are on for reverse.) If you have good (not slipping) forward and reverse your problem in likely minor. Check vacuum modulator and vacuum supply, check detent lever and valve for being stuck at WOT. I have also seen a small steel plug blow out of place in the front servo causing no shift to high. Good luck!

Username checks out.

swice · Nov 2, 2024

transmissionguy said:
Does your FMX have a strong reverse? If so you probable do not need a rebuild. Problems with the vacuum modulator, detent lever (kickdown) or a problem with the release circuit of the intermediate (2nd or front) band servo will cause delayed or no shift into 3rd. To shift from 2nd to 3rd the FMX requires intermediate band release and direct clutch apply. (forward and direct clutch are on for high gear. Direct clutch and rear band are on for reverse.) If you have good (not slipping) forward and reverse your problem in likely minor. Check vacuum modulator and vacuum supply, check detent lever and valve for being stuck at WOT. I have also seen a small steel plug blow out of place in the front servo causing no shift to high. Good luck!

Reverse was just barely working. 73pony located a working FMX thankfully. I’m going to find someone to break down the old trani. I’ll let you know what we find. Thank you for the awesome advice.

Hemikiller · Nov 4, 2024

For shipping, Fastenal sends palletized items store to store on their Blue Lane Freight service. I sent a 3 speed and steering column from CT to SC for around $120 a a couple years ago.

https://www.fastenal.com/fast/blue-lane-freight

swice · Nov 4, 2024

Hemikiller said:
For shipping, Fastenal sends palletized items store to store on their Blue Lane Freight service. I sent a 3 speed and steering column from CT to SC for around $120 a a couple years ago.

https://www.fastenal.com/fast/blue-lane-freight

Awesome advice, thank you!

FMX trani “toast”

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