Ford 4sp od oil leak

[Randall]

Working on Model A with 4spd conversion,leaking oil aroud shifting rails,I am wondering if it needs a vent,anyone have any thoughts?
thanks Randall

[J Franklin]

You need a manual for whatever transmission you are dealing with.

[JRN1967]

I couldn't find a vent in my rebuild manual parts list. So I don't believe they came with one installed.

Mine has sealed bearings front and back, with no vent. I don't have any leaks.

But it seems easy enough that you could remove the reverse light switch and add a vent there. Or pull the shift rail caps and apply silicone.

[Randall]

Thanks JRN
does your manual show shift rail seals?

[kenparker]

The "vent" in the F150 OD transmission is thru the shift tower, around the cup washer that is under the screw on cap. The washer and cap is not air tight around the shift lever.


The sealed bearings were put in by the OD conversion builder. Originallly they were NOT sealed bearings. There are no sift rail seals other than the caps/plugs that are in the ends of the rail channels. They wont leak if you dont mess with them.

[JRN1967]

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Originally Posted by Randall

Thanks JRN
does your manual show shift rail seals?

No it doesn't.

[Randall]

Pulled floorboards and washed it off , two of the shift rail end caps are missing,also is hard to get into 2nd gear where’s best place to get parts?
Thanks

[JRN1967]

Originally Posted by Randall

Pulled floorboards and washed it off , two of the shift rail end caps are missing,also is hard to get into 2nd gear where’s best place to get parts?
Thanks

These transmissions aren't easy to find parts for anymore. I bought a new counter-shaft at "The Gear Box" they had it sitting on shelf collecting dust. I sent them an email and got lucky.

You can also interchange the gear sets with the SROD transmission as well. The housings and shifter are different, but the gears are the same.

Ken is the expert, he advised me through my 4spd conversion. But J Franklin is right, you should really consider buying a manual.

[rotorwrench]

There may be some parts in the FoMoCo system but they haven't been in use since 1987 so they are getting harder to find parts for. They were manufactured down in Mexico at the Tremec plant down there. It's too bad they don't support them anymore. The guys who do the conversions tend to hoard the parts for good reason so other than flea-pay, they are the best sources for most parts. These are still sought after for more than just Model A Fords. They have also been put behind the Ford flathead V8s. The part numbers can be found in the 1985 thru 87 F150 and Bronco parts manuals for both the RWD and 4WD units.

[Randall]

stopped the leaks around shift rails,drove today and it is also leakig where speedo chain connects,must be getting by the sealed bearing,is this bearing easy to find if I take it out?

[JRN1967]

Originally Posted by Randall

stopped the leaks around shift rails,drove today and it is also leakig where speedo chain connects,must be getting by the sealed bearing,is this bearing easy to find if I take it out?

IM sent with the part number. I got mine on eBay, it shouldn't be too hard to find.

[Randall]

Thanks for the help! Removes diff. And this is a picture of it leaking while running

[Randall]

The numbers on bearing are a3082zn/c3gjn and 722052x

[JRN1967]

See bearing codes below.

My guess is your bearing is 6308 -2ZN, which is a bearing with metal shield on both sides (2Z) and a locating snap ring (N). This bearing does not have a rubber seal on either side. This is why it leaks.

Under normal conditions the RTS is sealed in the front by the input shaft seal, and sealed in the back of the transmission by the yoke seal for the drive shaft. When these transmissions are shortened, the rear bearing requires a seal on one side of bearing to prevent oil from leaking out of the transmission. You need a 6308-RS-N for one seal, you could use a 6308-2RS-N. It's easier to find the bearing with double seals and they are less expensive, because they are more common.

2 RS - Bearing with rubber seal on both sides.
RS - Bearing with rubber seal on one side, one side open.
2 Z / ZZ - Bearing with a metal seal on both sides.
Z - Bearing with a metal seal on one side, one side open.
N - Snap Ring

[Randall]

got the bearing out and got the correct one on the way! thanks to Ken and JRN and all the others for the help!