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FMX Transmission Leak Bell Housing
Got home from a cruise in and had a significant transmission leak under the car. Crawled under and its coming from inside the bell housing and leaking out of the inspection plate area. There has been a small oil leak before this and couldn't visually see it, but it appeared the oil was coming out of the inspection plate area. Transmission fluid is on my exhaust pipes so it looks like it leaking during operation.

Background: 351 Clev, 2V, FMX automatic. Just finished restoring the car so It hasn't been driven much since putting the engine and transmission back in around a year ago. Probably maybe have 100 miles on it due to the restoration. While we had it out we put in new rear main seals (replaced all seals), put in new fly wheel and torque converter.

Give me the bad news!

Frustrating as the car looks great and I'm dying to cruise in it and now this setback.

Attached Files Thumbnail(s)
The most likely suspect is the front (input) seal. The other possibilities are the pump seal/gasket and a split torque converter weld.

“If you can't explain it simply, you don't understand it well enough.”
--Albert Einstein
Where to get a very good quality input & output shaft/housing seal, part number/manufacturer please(still available by Ford dealer?).
Thanks for advice,
Unfortunately you are going to have to drop the transmission to change out the front seal, it can be done in an afternoon taking your time though. I can pull an FMX in less than an hour without much difficulty.

351w - Ford racing GT40X 178 cc aluminum heads - Ford racing(crane) 1.7 roller rockers - Comp Cams 280H magnum cam .544" / .544" lift - ARP fasteners - hedman longtubes - magnaflow exhaust with X pipe -  MSD digital 6al box - MSD coil - optima red top battery - tuff stuff 140 amp alternator - ported weiand stealth intake  - edelbrock 1406 600 carb  - march pullies and brackets - Be cool fan controller - derale electric fan - FMX trans - motive 4.11 gears - traction lok - competition engineering subframe connectors - lakewood traction bars.                                            

Well, the crazy part is this is going to be 4th time we have had to drop it. We have replaced everything and pretty sure we had the front seal replaced when we put in the new torque converter. Sigh...but becoming an expert on dropping it.
parforever;191414 Wrote:Well, the crazy part is this is going to be 4th time we have had to drop it. We have replaced everything and pretty sure we had the front seal replaced when we put in the new torque converter. Sigh...but becoming an expert on dropping it.

Yep. Looks like the front seal will need replacing. I know, more practice isn't what you had in mind...


[Image: 6y14ea.jpg]

Project started 8-7-10
Completed: All new suspension, rebuilt 351C H Code bored .030 over with mild cam and intake, new 3.50 TracLok, custom exhaust system
Current "mini-project": interior upgrade Undecided
I bit the bullet, dropped the transmission and having a complete rebuild done. Just don't want to drop the transmission again so hoping the rebuild will prevent me from doing it again.
A common mistake that happens when replacing rubber seals is ppl dont lube the rubber seal or
the shaft it is sealing resulting in a dry assembly and cooking the rubber seal quickly.
FMX's are a bit on the heavy side. I pulled one out of my 72 Coupe 25 years ago by myself when I was still young and in shape (well round is a shape), but an aluminum cased 5 speed is much nicer . . . .

[Image: 1_01_07_15_8_53_18.png]

"I love my Hookers!" and "Get some Strange" probably have a different connotation to non automotive enthusiasts!
My car is all numbers matching to include the transmission. Doing something different wasn't an option.
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