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WHile reading one of the posts, I became curious as to what gear ratio me rear end was. I went and looked on my door sticker and the axle code was 27. I have a 2003 F-150 4x4. The door sticker decoder said that i have a 3.31 non-LS and it also said that this ratio was only found in the F-250's. Is this a mistake? a misprint? I thought for sure that I would at least have 3.55's.
The decoder is generic from '97 -'99, sometimes it doesn't seem to make sense with its explanations but it works for most '97-'03s F150s. Go ahead and look at your diff tag as krunker suggested, this is nearly fool proof as long as somebody hasn't swapped gears.
I'm fairly confident you have a 3.31 open rear with the code you have given because the factory did not change that code from '97-'03. The axle code also does not vary due to ring gear size, which is another reason to check the tag. Ex: you could have a 3.31 in either an 8.8 or a 9.75 rear. If you ever need a replacement part, you'd end up checking that tag anyhow. Key is the second row, the first "3" is usually burried under the bolt, it will then look like this: "31 8 8" or "31 9 75".
It's been awhile since i've mesed around with gears and such (used to tinker in drag racing a lil') but, isn't a 3.31 gear ratio kinda high for a 4wd? I always thought that 3.55's or 3.73's came standard on 4wd's. Would love 4.11's though. I'll check the diff tag in the a.m. Thanks for your help!
Hi 03Ford4by4 and welcome to the forum
The shop manual does show a code 27 to be 3.31, non-limited slip in an F-150.
What engine do you have in your truck? Does the truck have many options?
Usually the trucks I see with gears like that are very basic and were ordered to be as cheap as possible.
I have the 5.4L V8, leather interior, fog lights, CD changer, power everything (seats too), and a few other things. The truck is a 2003 which I bought used in May of this year (had 20k miles). If someone special ordered the truck.....what idiot would get such a high geared diff?