What rear end do i have?

Clutch, transmission, rear axle

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gonzalo medina
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What rear end do i have?

Post by gonzalo medina »

1972 ford f-100 explorer...390 c6 The rear doesn't show bolts outside I think it's a nine inch due to the fact there is bo outlet through the back to come off and the bolts are on the inside.....if anyone can help I would sure appreciate the help want to make it posi(limited slip) thank you
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Post by heep70 »

You are correct. Its a 9in. Any tags on it? Should be one on one of the studs on the front of the center.
Greg

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re: What rear end do i have?

Post by gonzalo medina »

No tags amigo... Just as i suspected. So are these rears any good? Don't really have any knowledge on differentials/rears just simple common sense and a partime job to help me make this truck burn tire. I hear about the dana 30's 40''s and so on but really don't provide any help. I know my mustang is posi traction from the factory and that thing spins tire like no other. How hard is it to make a 9'' rear posi or is there a better rear out there waiting for me. My truck has a strong fresh 390 new c6 and am working on the rear and exhast.
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re: What rear end do i have?

Post by FORDification »

The 9" Ford rearend is about the strongest rearend you can get. It'll definitely handle anything you throw at it. Because they're so strong, these are pretty much the rearend of choice for anyone making serious horsepower, and even racers with GM or Mopar products are putting them under their cars. Because of their strength they're extremely popular, so you can buy replacement limited-slip carriers, full-on lockers or even spools.

Also, because of their drop-out third member, these rearend are often referred to as a 'poor man's Quick Change', a reference to the Halibrand Quick Change rearends (VERY expensive!). You can have several third members set up with different gear ratios and swap them out for different types of tracks or requirements in about 30 minutes or so.
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re: What rear end do i have?

Post by mrung0wa »

The only Axles beefier that I know of (that are worth a damn!) are the Dana 60 and 70 both of which are full floating one's and very heavy too!

The Dana 44 is a good and versatile one but nothing beats the ol' FORD 9" with the integral carrier/3rd member 31 spline is better/stronger than 28 spline (which are a strong axle to begin with).
There is 35 and an "Oh My God!":eek: 40 spline extreme duty monster axle available through Currie Enterprises here in So Cal.

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re: What rear end do i have?

Post by gonzalo medina »

There we go this is the kind of info that causes brain growth thanks now all I need now is help choosing a gear ratio. My truck has a freshly rebuilt 390 bored 30 over edelbrock performer manifold spacer+ edelbrock performer series carb 600cfm Hooker headers (new addition) replaced sanders headers, new c6 from kragen and a tci saturday night special torque converter for mild engine........out off breath... So what gear ratio should i go with as far as limited slip is concerned (Trac lock posi) what ever.
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Post by heep70 »

what are you minly going to use this truck for?

Here is a site on carrier info. http://www.ring-pinion.com/
Greg

1971 F250 "Highboy". SOLD to "Highboy_Firefighter_71"
2000 Subaru Outback limited.
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re: What rear end do i have?

Post by FORDification »

Well, you probably already know this, but as the gear ratio numbers increase numerically you get quicker off the line but sacrifice top-end speed and mileage. A ratio in the neighborhood of 3.50 is a good compromise between the two, and would be about right for a street-driven vehicle. Going any lower than that (high numerically) will be great on the street but mileage will take a major hit, since your engine's really going to be winding up out on the interstate.
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re: What rear end do i have?

Post by gonzalo medina »

First of all the main reason I am fixing the truck is because it's a tribute to my old man. And second off all these trucks look killer, mean, sick all of the above and no one has one hooked up in fresno. These trucks take up space in junkyards or worst case senerial abused hauling scrap all day I even see landscapers using them for work....My dad says ford trucks love being abused(LOL)...bUT ANY WAYS It's just to cruise and burn rubber from timt to time..... YOU KNOW... Maybe move a few things or mild street racing.
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re: What rear end do i have?

Post by 67effie »

If it's for burning rubber and just cruising go with some 31 splines 3.89's and a locker for the fun of it.
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re: What rear end do i have?

Post by broke_okie »

The 9" is the way to go . I have a 31 spline 9" with the factory limited slip and it is awesome. It is easy to install a limited slip into a 9" if you have the proper tools and are patient. There are so many choices for the 9" you will not have a problem finding what you need. If you do not have the proper tools I would suggest taking the 3rd member to Fearless gear since you live in Fresno,I live in Clovis and have fellow wheelers that use their svcs. I do my own usually. I cannot remember what you use your truck for but if you want a limited slip that has good street manners the Auburn is a good choice or the factory Traklock. I would suggest a gear ratio close to 3.50 for street use.
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Re: re: What rear end do i have?

Post by 390Nut »

gonzalo medina wrote:There we go this is the kind of info that causes brain growth thanks now all I need now is help choosing a gear ratio. My truck has a freshly rebuilt 390 bored 30 over edelbrock performer manifold spacer+ edelbrock performer series carb 600cfm Hooker headers (new addition) replaced sanders headers, new c6 from kragen and a tci saturday night special torque converter for mild engine........out off breath... So what gear ratio should i go with as far as limited slip is concerned (Trac lock posi) what ever.
Pretty much what I have in my `69, with the exception of headers (they're on the to-do list for this winter). I'm putting down about 325HP (estimated) as of now. Running 3.50 gears and couldn't be happier!

It runs about 2800 rpms at 65mph, but still has the ability to light em up easily from a stand still in 2nd gear (have a compound low on my T18 tranny) and will even break them loose if I'm moving slowly and really get on it.

Dunno what my mileage is like, of course I didn't build it with that in mind :lol:
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Post by rjewkes »

I'm thinking to get the better off the line speed and keeping close to the same milage and going with a 3.25 myself.

mine won't light them up.And it sucks cuzz from a dead stop it kinda luggs.unless i'm on loose material I.E. dirt,grass,gravel,wet pavement.

help me here i have 3000 rpms at anything over 70mph and about 2900 rpms at 65mph whats my ratio?

And aint the 9" a semi floating or is it a full floating?
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Post by Velcro »

Check your VIN plate. If the rear end is original, the code will show you that. All the info/code for location of that is on the home page here.

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gonzalo medina
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re: What rear end do i have?

Post by gonzalo medina »

Broke okie what's up dawg, it's nice to know I'm not the only one interested in these trucks around here. Willow/olive Let me know if you could help choosing a posi unit there's lot's of them on ebay. Want to finish my truck and start burning tire but heard fearless gear cost's an arm and a leg if you say it's easy show me how.
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