4 speed OD, or not?

[swinger340]

How can i identify my 4 speed as an OD, the guy i bought it from thought it was one. it came out of a 74' dart sport. i suppose i could put it in fourth gear and compare the rotations of the input shaft, to that of the output. also, it has an aluminum bellhousing. i can get the id numbers once i clean it off it anyone knows how to identify it that way. Thanks

[BB 70 Challenger]

Hello!

One of the most simple ways of figuring it out is IF the shifter linkage is still attached:

The OD 4-speed transmissons have got the shifter´s 3-4 rod attached to the side of the trans differently than conventional 4-speeds: the lever that the long linkage rod attaches to (front lever, closer to the engine) is UPSIDE DOWN, so it is very easy to identify such an OD trans just by looking at the front lever on the side of the trans.



And now the tricky stuff: so no driver knows anything about that linkage lever swap just by driving the car, because the shift pattern is just a normal H, still, even though INSIDE THE TRANS the old 3rd gear´s location is now overdrive 4th and what used to be 4th in normal 4-speeds is now straight 1:1 3rd.

If there is NO shifter linkage attached anymore and you want to count the gears by rotating the axles as you said, REMEMBER to do the counting when the real OD fourth is engaged (=other 4-speed trannies´ 3rd). You kow, if you just put an OD trans on 4th gear by hand without a linkage by figuring the right lever position the way normal 4-speed trannies have it, you end up counting a straight 1:1 ratio just like nothing happened! The trick is the old 3rd being the sought after OD gear now....

Best Regards, - BB 70 Challenge

[dwayne penner]

Uh this might be too easy, but didn't all the 4 sp OD trannys have aluminium cases?