FMX filler tube leak help

[69rangerman]

I finally found out that my tranny was leaking from the filler tube where it goes into the case. I did purchase a new O-ring (2 in fact), and it slowed it down a little but I think the filler tube is just a bit to tweaked, dented, and out of round to get a good seal.

Does anyone have any ideas about other / additional ways to improve the seal in this area?

Would C4 or 6 tube work?

Thanks for any reply.

Tom/FL.

[FordTruck]

I got the filler tube off of the old FMX that I had in my 70 if your interested.

[fordman]

it could be the size of the oring you are using. there are several types and sizes of those. the one you have may not be think enough. it may be the correct size around. but it may not be think enough the other way. if you know what i mean.

[ares360]

are these trannys any good?

[FordTruck]

are these trannys any good?

I've herd mix things about them. I have the one out of my 70 it was rebuilt but it started slipping really bad so I switched out for a C6. I probably could have chanded the filter and fluid and maby adjusted the bands but too much work for me so I took the easy route

[ares360]

ok, cause I might have picked up a 400 ci small block with an fmx. I guess I will just have to see what happens.

sorry for stealing the tread 69rangerman

[fordman]

c6 is better than a fmx

[FordTruck]

c6 is better than a fmx

Agreed, isn't an FMX just a built C4?

[F-100Ranger]

I see the comments about the C-6 being better than the FMX all the time.

To quote Stuart Anderson from the Ford Transmission Forum at www.network54.com
"The C6 will use lots more horses than the FMX. If the FMX is done properly it will stand up to what the C6 has to offer."

There's something like a 14 hp loss for the FMX vs. 45 hp for the C-6.

[69rangerman]

I've done alot of reading on the FMX vs. others, including the Stuart Anderson website. I try to keep this one going because it's original to the truck along with all the other major bits. I wish I could afford to have it rebuilt, and that there were more repair parts for it.

My opinion is that any tranny that was originally spec'd behind everything from a 302 to a big block in some wopper 70's lead sleds is probably a very durable tranny, and able to take some pretty good torque.

I also like that it is fully manual and gears may be selected and kept as long as required.

Anyhow...my latest attempt at the fix is to use a few different types of o-rings from True Value, and lock them in place (they keep slipping up the tube) with a small metal hose clamp above them.

I let it run for a while and will know in a few days if this helped.

Thanks for the replies.