Rear Axle Ratio...how do I know what I have?
 

My new to me 03 EB Exc 4x2 is equipped with the factory towing package. I'm not towing that much - a 4500lb max weight popup camper. How can I determine what the axle ratio is in the rear end of my truck? Oh, it is a 5.4l v8 - and no, it doesn't win a drag race - but it sure moves quickly enough for hauling my family around safely!

thanks...

Post the info from the tag on the diff
or
search here for VIN # decode info

Both of the above assume that the ratio is still matches the tag/VIN. 100% sure method is to count teeth; prolly overkill for your purpose.

Even easier than that:

If it's close to this:
Attachment 223460

Then you have 4.10:1 gears.
If it's below 2k rpms at 60 mph, then you have the 3.73:1 gears.

Yup, I have the 4:10s and that looks about right.

The picture is from mine and it is the 4.30:1 but the OP has the V8 so it would be the 4.10:1 instead. (or 3.73:1)

I said "about" :-X22

If you want to know your "rear axel" look in the drivers door jam:
You will see an axel code
If your axel code begins with a LETTER you have a posi rear-end
Get the axel code and look up the code for ratio.

Your Excursion being 2WD with a 5.4 engine should have a 4:10 if the axel code starts with a letter then it should have a posi-track rear end, if not a standard 4:10 rear end. Unless it has been changed over the years.
There are exceptions but few.

My axle code is "31"

At ~60-65mph I'm turning just under 2k rpms - 18-1900 or so.

Don't think anything's been changed - vehicle is all stock. What is better for towing? 3.73, or 4.01? Does it matter too much if my fully loaded pop-up is no more than 4500lbs?

thanks

Axel code 31:
3:73 NON Limited Slip.

Which means...?

You have a 3.73:1 ratio axle and you do not have a limited slip (traction device) installed.

4.10s would be a better match for your truck (IMO) but sounds like things are working out for you as it is now. :)

I also means that as long as you are happy with the way it tows, save your $750 and keep driving it the way it is. (Regearing costs about $750 per axle to have a quality shop do it.)

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

An axle code is supposed to be two characters. Are you sure it only says E?

I called my local dealer with my VIN and they looked up my axle for me.