I am trying to replace the entire (drum to drum)rear end on my '77 F150 4x4. I have a 4x2 rear end which needs new pumpkin and I was wondering if any ford drop out with the correct gears work? Are there any differences in the axle spline count between a 4x4 and 4x2 rear end? Please help!!

 

[font size="1" color="#FF0000"]LAST EDITED ON 02-Mar-01 AT 01:29 AM (EST)[/font][p][font size="1" color="#FF0000"]LAST EDITED ON 02-Mar-01 AT 01:27 AM (EST)[/font]

Some nine inch pumpkins require 31 spline axles, some require 28 spline axles. The pumpkin tag has code, that the wrecking yard should be able to decipher. I think the first group of letters above the ratio number is the relevant code... like WDM-A (an example, not nessesarily real) If you get axles's and pumpkin together from same source you should be OK if you don't have code. Count the splines on your axles so you know what you have. My two 2wd nine inchers that I have are both 28 spline, but I have seen 31 spline in wrecking yard. Several wrecking yards have told me that 31 spline 3.50 gears are being sold for like $400 to 4X4 guys. Maybe you should measure your 4X4 axletube for length and springpad spacing to compare to a 2wd example?

BBT

ps, I'm parting a 69 F100 2wd, that has a Dana half ton style limited slip 3.5ish rear gear, in the Seattle area.

 

Thanks for the help. What you have it what I am looking for but the shipping would not make it worth the effort. I am in Texas. Thanks anyway!

 

Jason, a two wheel drive axle should be fine. The differences are from year to year, not 2 vs 4 wheeler. Both 2 and 4 wheelers came with narrow and wide axles, 28 and 31 spline. I think the wide axle with 31 splines started in 1973, but I'm sure your 77 is wide and 31. What is wrong that you need to fix? DF

 

When i bought the truck (77 4x4 F150)it had a 1 ton rear end with the wrong gears in it (3.50 front 3.00 rear) . I found what I thought was the correct 1/2 ton rear end but when I tore it apart to count the teeth it turned out to be a 2.75 when I need 3.50. Now I have a half ton with the wrong gearing. I am looking for just the pumpkin now. that is why I was wondering if there was a difference. If there is not, I can just swap out the pumpkins if i find one. I am very new at all this and learning new stuff every day! How can I tell what is narrow and wide? How much difference is between the two?