Differential Swaps | Ford Explorer Forums - Serious Explorations

  • Register Today It's free!

Differential Swaps

mbrando1994

Well-Known Member
Joined
May 17, 2015
Messages
274
Reaction score
6
Year, Model & Trim Level
2003 Ford Ex XLT
4.0 V6
I received a few diagnoses that both my front and rear diffs are on their way out, my options are either to rebuild them, or replace them with used parts found at a yard. I don't have the funds to rebuild right now nor do I have the money to pay for labor. I'm pretty experienced with auto repair but never tackled a job this in depth. How do I know if the diffs I pull off of a junk yard car will be the exact same as mine? Do they even have to be? Obviously I'll be looking for one with AWD, same year, model, etc. Are there any tips/tricks to help me out here, thanks!
 



Join the Elite Explorers for $20 each year.
Elite Explorer members see no advertisements, no banner ads, no double underlined links,.
Add an avatar, upload photo attachments, and more!
.





Take a look at this post, http://www.explorerforum.com/forums...er-door-sticker-axle-codes-deciphered.309965/
Basically you want to find a donor vehicle with the same door code for the drive train that you have on yours. If you choose to change your gear ratio, then be sure that the front and rear are the same! The only problem you might have is that the differentials you find may be worn out as well.

Also, some years, the rear differential has a single speed sensor for the antilock bake system and other years used a speed sensor on each rear wheel. You should look for a differential that has the same sensors, or you might run into problems getting your antilock and/or traction control system to work properly.
 






Interesting, so the code has to match exactly then? Hopefully I get lucky, I'm worried I won't be able to free it from the yard vehicle without air tools though
 






It will make things easier if they match up. The gear ratio and speed senor set up are more important. If you don't want to go to a local salvage yard or pull it yourself, you can search on http://car-part.com for the exact part you want and see what is around you. Prices will range more, but you can get an idea of how many miles are on the part, general condition, and often a picture.
 












If you rebuild yourself it won't cost more than $300...

Something like...http://www.ebay.com/itm/Ford-Racing...-M-4209-88373-w-Installation-Kit/171179716852

Need to know your axle code to link you the exact kit you need.

EricTheCarGuy on youtube has a great video on how to do a differential rebuild. You will need a feeler gauge.
Yes I've watched many of his videos, problem is, this car is my daily driver and I only have one. I would need to get a used diff and rebuild on the side before swapping, that way I minimize the down time. I've never rebuilt a part before, so I'm expecting it to take me some time
 






If you rebuild yourself it won't cost more than $300...

Something like...http://www.ebay.com/itm/Ford-Racing...-M-4209-88373-w-Installation-Kit/171179716852

Need to know your axle code to link you the exact kit you need.

EricTheCarGuy on youtube has a great video on how to do a differential rebuild. You will need a feeler gauge.
My code is 45, so 3.55 NLS, What typically goes on these differentials when they do fail? I believe they were left run dry. Also, are the kits universal front and back? Or different ones for both?
 






It's usually the bearings but then driving with bad bearings (causing mis-alignment) damages the ring and pinon gears...

If you plan to do the front and back as a set at the same time I would upgrade to 3.73 or even 4.10 if you'd like to be able to do a lot of towing.
 






Back
Top