Axle Code 2 Gear Availability Issue

Help Support 7173Mustangs.com:

cv_72mustang

VIP Members
Joined
Apr 14, 2019
Messages
206
Reaction score
41
Location
PA
My Car
72 Vert 351C White
Hi,  

I have a question and looking for feedback concerning my 72 351C vert   I've been slowly doing a rolling restoration and next in line was my very noisy differential.   I'm trying to keep the car stock and original. Just a plain old weekend car.   Going in I knew it was a  2.75  standard diff mated to an FMX trans.  It's all original and the diff tag matches.  

The rebuilder is having trouble finding a 2.75 gear set 'domestically' made and says the closest would be a 3.0 ratio. The wear pattern is bad and he is concerned if it's not replaced along with the bearings it will whine.  

1. Other than some loss of higher speed and maybe a little better acceleration do you see any other issues with this change?

2. Also, I suspect the speedometer will be off a bit, is this correct and could I change the speedo gear cable for a FMX trans. 

Thanks

 
Last edited by a moderator:

Bill73Ragtop

Long time vintage mustang hobbyist
Joined
Apr 19, 2011
Messages
1,419
Reaction score
32
Location
Buffalo, NY
My Car
1969 Convertible Restomod enhanced.
former owner (25 yrs) of 1973 Convertible, 351c, A/C, RA
If you're going to the trouble to replace the 2.25, think hard about a 3.25. It's almost the perfect balance between around town get-up-and-go and highway cruising.

The 351c will handle higher rpms (2800 - 3200 +/-) at 70mph all day long. A 3.00 is almost no difference from a 2.75.

Depending on overall mileage, a new convertor (1800 stall) is a nice match up and you won't have to worry about older factory stock unit giving out.

 
Top