Hi, I live southern NY and put roughly 1,000 miles a year on my 55 T-Bird 3 sp OD. How often should I change the trans and differential oil?

1955 312 T-Bird Warwick, NY

I drive more than 1000 miles a year, but I’ve been changing at 10,000 mile intervals for the last 20+ years. Don’t make the same mistake I did though, and use modern lube in the trans. (syncro failure forced a rebuild), as that likely contributed to deterioration of the original (bronze?) parts.  Also, the different levels of fill plugs can be confusing, as it takes time for the thick lube introduced into the higher OD port to transit & drain from the trans. port (I believe filling the trans. first may lead to overfill, though the consequences of that are uncertain).

6 VOLTS/POS. GRD. NW INDIANA

Use only API rated SAE 90 gear oil type GL-1 Napa part # 65-201 or can be ordered from fifthaveinternetgarage.com
Fill the overdrive section first until it overflows then fill the main case. If the old oil is turning black it has oxidized, change it earlier.

1955 312 T-Bird Warwick, NY

The correct trans oil is also available at Tractor Supply under the name Traveler Ford Tractor Transmission Oil. DO NOT use diff oil (hypoid) in the trans or anything labeled for use in both.

Good advice 🚗

1955 312 T-Bird Warwick, NY