okay so about a year ago i aquired a sterling 10.25 rear end that im going to be using for a 3/4 ton axle conversion on my89 bronco. i posted a thread asking how to determine the gear ration for the rear end. someone posted that if i crack open the dif cover the gear ratio should be stamped on the ring gear, well i finaly had the time to do that the other day and instead of finding a straight up ratio stamped on the ring gear i got this number e5tw-da-10-41-5jd, does anyone out there know how to determine the ratio from this number?
the truck this came of of was an 85, 86 f-250 the axle code was kinda smudged on the vin sticker but im sure it was either b5, or 35 those were the only two possibilitys i could gather for the axle code when i researched it the ratios for both were 4.10, the only difference was thatone was semi floating the other was full floating, which is what i have (full floating) can anyone help me determine this ratio, im hoping its 4.10
any help would be great thank you

 

IM/locate numberdumby. he is the part number king.

so does that rear diff have a tone ring and spot for the rear sensor on top of the diff? if you have an e4od you may have issues

 

its a standard shift, got the little m5od, plus im going old school with the truck, 460 carb, np 435 4 speed,np 205 t-case, dana 60 in the front, the sterling in the rear no computers or controllers how do i contact number dumby?

 

Why not just rotate the pinion until the the axle turns one full turn? If it turns more than 4 revolutions, its a 410. I think they only came in 373 and 410. Just make sure both axles/tires rotate one full turn.

 

Count the teeth on the ring gear and pinion. Then divide.
Example ring gear =41 pinion = 10.
41÷10=4.10