Axle code, now I'm confused
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From: Casa Grande
Axle code, now I'm confused
Ok, my 85 F150 4X2 has an axle code of 17. Found a chart that says that's 3.31 gears. But now I have found other charts that say it's a 2.47 and some that don't even list that code for 85. So what gives? It's not the original rear in there now but would like to know what was factory on it so I have somewhat of a guideline. My plans are to find a 5/od trans with a slightly lower 1st then do the rear to a good over all ratio. But knowing what the factory trans/rear gears and tire size were would help.
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From: Virginia
My info says 2.47 to 1. If it originally had a six, this is a common setup for fuel mileage. That old six can lug along at low rpms with that rearend and be fine. If someone has swapped in a 302, then they might have swapped in a different rearend so the thing would be able to rev up a little bit with the v8.
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From: Casa Grande
Thanks for the reply. 2.47 sounds more like it. I know the friend I got it from told me it was a real dog off the line and had to really be revved up to take off. Think it has 3.50 or 3.73 in it now but may be as high as 4.10, never have checked it. Never was that important to me till now, with gas at over $3 a gallon. Last trip I took in it it got less than 14mpg so think it might be time to do something.
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From: Casa Grande
It has a 4/od in it now but thinking about maybe doing a 5/od trans with a slightly lower 1st gear. Then maybe 3.00 to 3.25 rear if that wouldn't be to high for the 31" tires on it.
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From: Loganville, Ga
I have the same setup, 300, 2.47, 4spd/OD. Well almost, I also have an Offenhauser intake and 500cfm Edelbrock. I'm getting 18mpg. I can't use OD unless I'm over 60mph. Any less and it lugs to much. Which may be the reason for the 18mpg, it lugs to much. If you putt-putt around town it's ok.
I am strongly considering a change to 3.08 or 3.27. I searching the forums right now for other threads before I ask though.
I am strongly considering a change to 3.08 or 3.27. I searching the forums right now for other threads before I ask though.
