I need information regarding the 1950-54 Rear Axle Ring and Pinion Gear from a Powerglide transmission. The 1929-1957 parts book has casting number for the Ring Gear with 3691464. The rear axle I bought has 3691463 casted in which does not show in the book, can someone identify if this ring gear is the same as 3691464. I am switching out my gearing from the standard transmision to the powerglide transmission because I was told it had better highway gearing. Hope this is true.
That is the 3.55 gear. Set number in my 55 book list 3691464-3704411 make up the 3805262 set. It also showed the 3691464 used with 3705723 for 1955 w/PG. Still same ratio but the 1955 used an open driveline.
Steve,
thanks for the reply. Please reread the original post, I had the part numbers switched but I corrected the post. The physical casted part has part number 3691463 cast in the part.
Hi Johnny, my '29-'50 parts list 3691463 as 1950 all pass. w/pg., cast no 593009 on housing.
Should be 3:55, 11 and 39 teeth
The 3691463 is the part number for the CASE and not the gear. Best to get the number off the ring gear and the pinion gear and also to count the teeth on both to verify the ratio . The 3691463 case was for cars 50-52 with Powerglide and 53-54. My parts book list the casting number for 3691463 as 593009 . I also saw a case listed on Ebay and it had the 3691463 cast into the case with the 3691464 gear on it.
I believe the case you refer to has a different offset, and is necessary when using the Powerglide 3.55 ring and pinion where 4.11 used to be. I could be wrong, but it is a detail that should be nailed down before attempting to change a ring and pinion.
Steve you are correct, 3691463 was the cast number on the case. So what I have is the differential gear cluster and shaft leading down to the transmission. I was able to see the top of the pinion gear which had stamped on it "GM 1 4 54 11-39 3704411". I'm assuming the first 3 numbers are the date code (1-4-54) the second set of numbers are the number of gears (11 for pinion, 39 for ring) and then of course the part number (3704411). I did count 39 gears on the ring gear, so it looks like this is the 50-54 w/PG.
Next question: I plan on switching out this assembly with the one I have on my 1940 sedan delivery. I was told that the 50-54 w/PG rear end had better highway gearing, it that true? To be honest I am not that educated on this topic. I'm not familiar with what 3.55 and 4.11 actually mean...
Your present 4.11 gears mean the engine will be turning over about 3100 RPM at 60 MPH. With the 3.55 it wll be about 2750 RPM at 60 MPH.
High gear will have less pulling power under 50 MPH and gas milage will be about 5% better.