Fmx shift shaft seal replacement

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Tucaz520

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Has anyone pulled this off?

Ive been turned away by 2 shops. They dont want tk touch it unless its a full rebuild.

 

Tucaz520

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Yes, I have done it on a bench.  

It isn't that bad
Would you have been able to accomplish it while still mounted in the car?

That may be why no one wants to touch it unless its a full rebuild.

 
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I honestly don't know the answer to that yet. In a couple months I should have the transmission back in the car and I can take a look.

The exhaust may be in the way, I'll dig around in my pictures and see if I have any that show how long the shaft is so you would know how much clear space you need to pull it out.

 
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The biggest issue will likely be getting to the two nuts that have to be removed from the inside ends of the shift lever shaft and the kickdown shaft. You may have to remove the valve body. I had to modify an end wrench when I did the seal on a C6 in the car. And, as Bentworker said there may be clearance issues on having enough space to pull them out, may require dropping the exhaust down, or lowering the back of the transmission. Be prepared to have transmission fluid drip on you, no matter how long you let it drain.

 

Tucaz520

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I honestly don't know the answer to that yet.  In a couple months I should have the transmission back in the car and I can take a look.  

The exhaust may be in the way, I'll dig around in my pictures and see if I have any that show how long the shaft is so you would know how much clear space you need to pull it out.
Didnt even think of it being a clearance issue. 

That may further explain why a shop doesnt want to replace just that seal. Ill look under the car tonight and see what it looks like.

 

Tucaz520

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The biggest issue will likely be getting to the two nuts that have to be removed from the inside ends of the shift lever shaft and the kickdown shaft. You may have to remove the valve body. I had to modify an end wrench when I did the seal on a C6 in the car. And, as Bentworker said there may be clearance issues on having enough space to pull them out, may require dropping the exhaust down, or lowering the back of the transmission. Be prepared to have transmission fluid drip on you, no matter how long you let it drain.
The valve body does have to be removed. The seal installs on from the inside.

 
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[url=https://ibb.co/byqWMF][img]https://preview.ibb.co/gNvy1F/IMG_5370m.jpg[/img][/url]
Has anyone pulled this off?

Ive been turned away by 2 shops. They dont want tk touch it unless its a full rebuild.
Hi! I have done it twice. The first time I did it with the transmission in the car and the second time I was installing a shift kit and changed the converter so I did it on a work bench. The procedure is not that hard! If you take your time I am sure you can do it by yourself. If you area changing the shift shaft seal also change the downshift shaft o-ring, it is inexpensive and since you already took out the shaft you may as well change it. If you have a leak the o-ring can be part of the problem. 

I got both from ebay, this is the link:

https://www.ebay.com/itm/Shifter-Control-Linkage-Kickdown-Lever-Reseal-Kit-Fits-All-FMX-Transmissions-/111971586176?hash=item1a1206d080

And since you will need a new gasket you can buy the full kit:

https://www.ebay.com/itm/Oil-Filter-Service-Kit-with-Shifter-Control-Lever-Seals-Fits-FMX-Transmissions-/112011902821?hash=item1a146dff65

There is a thread with a step by step on hot to do it here in the forum:

https://www.7173mustangs.com/thread-fmx-transmission-shifter-seal-replacement-how-to?highlight=FMX+transmission+shifter+seal+replacement+how+to

you can do it with the transmission still in the car, I didn’t try to do it without removing the valve body. In my opinion, it is easier to remove the VB. It is really easy to remove and you have more space to work and have better visibility of what you are doing.  

I don’t have a stock exhaust system so I don’t know if it gets in the way. In my case, there was no issue with the clearance.

This area some pictures of how it looks with the valve body and how it looks without the valve body. There you can see the shafts.





And since you are saving yourself from a full rebuild, there are a few easy upgrades you can do while you are at it. 

  • Shift kit. 
  • Since you disconected the link to the shifter it is easy to change the shift selector bushing. If your shifter feels all loose, this will solve it. 


Hope this help!

 
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Not sure if i understood your question correctly.

If you mean can you fit a new seal where the selector shaft is. The answer would be you can do the job without removing the gearbox. You can access by dropping the oil pan.

 

summerboy

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I am in the process right now, transmission is still in the car. Removed the valve body, had to lower the exhaust to get the shifter seal out, It is quite a job in total, you have to take your time fot it  :angel:

 
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