thank you for the help yet again. but another question,alright i want my truck to be able to beat those little pee butt h**das and such not serious raceing tho! now heres the question would that be a good setup haveing a
C-6and a 351M will it proform? or should i change out the rear end and if so to what? thank once again

 

What size tires are you running (diameter)?

 

about a 27 in high tire.I tired the vitrual engine calculator and it gave me 160 MPH at 5500 RPMS butt that sounds crazy for a truck?would that calculation be correct? thanks again

 

Here's the formula:

MPH = (RPM x TireDiameter) / (GearRatio x 336).

If you have an automatic without a lock-up converter (C6, C4, FMX), use 355 instead of 336.

(5500 x 27) / 2.75 x 336) = 148,000/924 = 160.7 mph.

That's great for top speed, but doesn't do you much good for acceleration. You need lower ratio gears (which are numerically higher).

With 27" tires, 3.50 gears would be a descent ratio for the street that will still allow you to cruise on the highway. According to the formula, top speed at 5500 rpms would be about 126 mph.

You can go to a lower (numerically higher) ratio for more acceleration and less top speed if you like, but fuel mileage will suffer.

27" tires and 3.50 gears is about the same as 4.10 gears in an F250 truck with stock ~31.5" tires, so that's about as low a ratio as you'd want to go if you don't have an overdrive gear and use the truck for other things besides waxing rice burners.

[On Edit: I re-read what you wrote. I see you have the C6. Use '355' in the equation, and since you don't have an overdrive gear, 3.50's are about as low a ratio as you would likely want to go to for general purposes. 3.25's will give you a better mix of power and speed, if off the line acceleration is not so important to you. Fuel mileage at highways speeds will also be a little better with the 3.25's.]

 

alright so 3.25 or 3.50? which rearend is more common and easier to find? and what vheciluar to look in. thanks alot

 

You can use the 3rd member section from any 9" axle with the same axleshaft spline count as what's in your truck (28 or 31). This will be easier than swapping the whole axle. 3.50's came in some pickups and Broncos. Not sure which you will find more of between 3.25 and 3.50. There is always the option of having a new set of gears installed in your existing 3rd member too, then you can have any ratio you want without the hassle of hunting one down all over town. That would also be a good time to put in some kind of traction differential if you don't already have one .

 

Man, that is a lot of code decifering!!! well done!!!
Just what i was looking for.
Mark

 

HOLY SCHNIKEES!!!!! Purple, i hope u did the copy n paste thing, if not, that had to be a TON o work. thank you! imma gonna go decode my 84 F-250 b4 i throw my zf 5speed in her.

 

just snooping through this old post on axle codes, very informative by the way purple 55, my axle code is 19 on my 87 4x4, the code reads( 3.55 ford locking) could someone explain what ford locking is, I see some say ford non-locking thanks

 

Trying to figure out what rear end is in my 02 eb 4x4 4.6l Explorer
PM V 652B
73 88 2E14
Can someone desifer this for me please?
Thank you

 

Is this off a tag on the diff?

If so, look again, there may be a "3" in front of the "73 88 2E14". If so, you have 3.73 gears, open diff.

The first digit is often obscured by the bolt holding the tag on.

 

Thanks, i'll check when i get back outside. What i think i have found is that it is 373 gears limited slip. How do you read these tags?
Thanks

 

On the tag, if it says 3 73 xxxxx it's a 3.73 open diff.

If it says 3 L73 xxxx its a 3.73 limited slip.

The axle code on the door jamb plate will also tell the tale.

http://www.venturestruckparts.com/?m...identification

http://www.woodyg.com/fairlane/finfo/fordrears.html

http://www.therangerstation.com/tech_library/Axles.html

 

Hi everyone .. I need ur help .. I have 01 v10 x limited with towing package the tag on the inside of my door say axle e ... What size gear does that mean??? Thank you for your
help

 

E...sure that isn't the trans code? Read more:

https://www.ford-trucks.com/forums/7...axle-code.html

https://www.ford-trucks.com/forums/2...tio-codes.html

http://www.drivetrain.com/parts_cata...s_it_posi.html