So I have a 77 f100 and im trying to figure out what gear ratio I have. The rear axle code is 47 but I cant find anything on this code. Any help is appreciated!

 

Look at the warranty plate again, make sure the "4" isn't a disfigured "H".
I didn't find a "47" axle code in the parts book but if it is an "H" and the axle code is H7, you have a Ford 9" 3.00 limited slip.

 

Thanks for the reply!Its definitely 47 on the VIN tag.

 

Mike... While were on the subject. . how about 78 f100 with 02J .no tag on rear, just the one on the truck. when I checked a chart I found online it came back Ford with 2.75 ratio, I believe the 2.75 which is another reason I'm sure its the original rear. But it does not look like a ford 9. Almost appears smaller. But definantly chunk undbolts from front.

 

47 = Dana 44.3 Rear Axle / 3.07-1 / 3,300 lbs. Rear Axle Capacity.

Mike: This is listed for F100/150 in my 10/88 microfiche catalog, it's not listed in the hipoparts C/D catalog (except as F500/750 Rockwell R/A).
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redneck davis: 02J: 02 = Ford 9" Rear Axle / 3.00-1 / 3,300 lbs. Rear Axle Capacity / J = Power Steering.

 

To verify - mark the driveshaft, raise the rear-end (get the tires off the ground), hand-turn the wheel-tire one full rotation and count how many times the DS turns. (If you have a 3.07 - the DS will turn just a little further than 3 full rotations. If you want to REALLY verify - turn the wheel 14 times. A 3.00 gear would give you 42 DS rotations - a 3.07 would get you a hair under 43 rotations. [42.98 to be exact.]) Math can be fun!

 

Well it must have been swapped out because it looks like I have a 9 inch now and not the dana 44. Thanks for the help

 

So the 2.75 mine came to is wrong?Decoding '73-'79 Ford Truck VIN Tags - FORDification.net
I will update with pictures Fri night or possibly sat. I doesn't look like any 9 I have seen before. Possible Ford 7.5?

 

Ford's 8" rear is the same design as the 9" with the removable "chunk". Before I swapped to a 8" in my '67 Mustang - it had the puny 7.25" rear, but those are axles with the pan on the back (not the chunk.)

 

Ok. Very sorry guys. I was very wrong about what it looked like, but was right about it not being the 9 my code says it is








Now after someone told me it was a Dana on NY truck build thread, I searched for numbers and could not find a model back at the rear of it,to the right, in the lower triangular portion where its suppose to be. LMC says to check the front(somewhere??)
Can anyone tell me what model or info from the stamp on the tube? It reads: 7 digit number is 603903-1
Then 7-11-8-B8

 

1977/78 F100/150:

Ford ID number: D7TA-4001-JA / Dana ID number: 603903-1 = Dana 44.3 Rear Axle / 2.72-1 / 2,900 lbs. Rear Axle Capacity.
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AXLE code 02J:

02 = 1973/77 F100/150: Ford 9" Rear Axle / 3.00-1 / 3,300 lbs. Rear Axle Capacity.

02 = 1978 F100/150: Dana 44.3 Rear Axle / 2.72-1 / 2,900 lbs. Rear Axle Capacity.

J = 1973/79 F100/350: Power Steering.

 

That's looks like a dana 60.How many bolts on the wheels? Ford did make dana 60 with 5 bolt wheels.

 

Ford never offered a Dana 60 with 5 lug wheels, since Dana 60's were only installed in 1955/85 F250's & 1975/2014 E250's that came with 8 lug wheels on a 6.50" bolt circle.

But...Ford did offer the Dana 60.2 in 1963/66 F100's & Dana 60.3 in 1966/69 F100's. 1953/79 & some 1980/83 F100's have 5 lug wheels on a 5.50" bolt circle.

 

Kind of confused about 2 separate axles with the same code... But a Dana 44 with 2.72 gears makes sense. Thanks numberdummy

 

Ya I,m confused too, what kind of diff are we looking at?