i am looking at a 77 350 dually, with a 390 4spd, for the intent of swapping the axles out into my 90 f150 (and possibly the motor too, since mine is only the 302) my question is, does anybody know what gear ratios came in the rear ends of those? i understand i will need to look at the tag and whatnot, but does anybody have a rough idea, or know for sure?

thank you!
Andrew

 

390's (and 360's) were not installed in F100/350's after 1976, have 5 valve cover bolt holes.

1977 F350 with/without DRW = Dana 70 rear axle / Without Limited Slip: 3.73 / 4.10 / 4.56 / 4.88 / With Limited Slip: 3.73 / 4.10

This is assuming "as original" / If it has a 390, there's no telling what else could have been swapped. 'Course it might be a 1976, as both years look identical.

If it has 4WD, that's not original...period / 1979 F350 was the first year for factory installed 4WD

None of the engine mounting parts will work after 1979.

 

Sounds possibly like taking one frankenstein apart to build another frankenstein but hey, if it works, go for it

 

he is pretty sure that it has dana 60's in it. does anybody know the ratios on those? other than the tags on the pumpkins (since they may not be readable anymore) is there any way of knowing what axles it has? like by bolt pattern? vin? haha. any other axle code on the door jam sticker? obviously those wont matter if they are swapped. and it might not be a 77, who knows haha

 

Dana 60? I'll teach ya to fish...Look up and decode the Bill of Material (BOM) number stamped on the axle housing.

Then go to this page: http://www2.dana.com/expertforms/depdf.aspx?prod=AXL

Then go to the bottom of the page and find the application catalogs for the year truck. They're the 3rd, 4th, and 5th catalogs from the bottom.

"haha"? Wassofunny?

 

Dana 60 front and rear axles factory installed in 1979 F350 4WD's.