Topic: 69 Dearborn S Code Mach 1 Question

[G Wood]

My Jan Built S Code Mach 1 has the axle tag missing. My Marti report says my axle code is 9 = 3.25 standard axle ratio. The car is equiped with a four speed manual.

Should my car have the 28 spline axle (which i think is correct) or a 31 spline. For my knowledge, what was the deciding factor on whether cars received a  28 or 31 spline cars?

Thanks

[J_Speegle]

Also believe its going to be a 28 spline but lets double check. If you can provide the info off the rearend tag we can make sure what it came with originally

Guessing it might read WCZ-W

[G Wood]

Jeff:

As mentioned, I am missing the rear end tag.

Garth

[J_Speegle]

Sorry I missed that info in the first line

Looks like the Ford books I have your car would have received a rear axle marked WES-AD


It was a 28 spline 4 pinion open rear end

Ford must have had a list showing the recommended ratios and from there someone at the factory had another that converted the request into what was installed. Appears that high performance engines got the 31 splines axles and everything else (that received a 9") got the 28. A buyer may have been able to up grade by purchasing certain performance gears on a non-high performance engined car but don't recall seeing an example of this in a 69

[G Wood]

Thanks Jeff, so I think what you are saying is the Boss and 428 cars rec'd the 31 splines and everything else (S Code included) with a 9" rec'd the 28 spline.

Garth

[J_Speegle]

Thanks Jeff, so I think what you are saying is the Boss and 428 cars rec'd the 31 splines and everything else (S Code included) with a 9" rec'd the 28 spline.

As standard equipment - that is my current understanding