Front diff swap tips?

InvisiBill

Active member
Ok, my new front diff got here, and I'm going to try putting it in myself to save a bunch of cash on labor. I have two repair manuals which provide helpful instructions like "Remove all the stuff in the way, then unbolt it. Reverse these steps to install."

Anyone got any practical tips for getting this thing swapped out as quickly and easily as possible? I'm fiending for some boost...
 

Captain Morgan

Moderated User
Re: Front diff swap tips?

1. Buy an offset 18mm box wrench (if you dont have one), I also suggest buying a cheap one. I ended up modifying mine (cutting it shorter) to make it more user friendly. You will need this wrench in order to hold the nut inside the driverside frame rail for the upper diff mount bolt.

2. Remove propshaft.

3. Remove the 12 bolts that hold the CVs to the front diff (6 on each side). You may need a chisel and a hammer to pop the CVs off the axel shafts.

4. Remove the center link. Disconnect the tie rods from the center link on each side, followed by disconnecting the idler arm, then at the pitman arm.

5. Remove the diff mounting bolts.

6. Lift and tilt the whole diff assemble so that the passenger side axel shaft and tube are below the lower control arm.

7. Remove the 5 bolts holding the black axel tube to the diff case (be sure to have a pan under it, fluid should leak out).

8. Lightly tap around the axel tube to break the seal and allow fluid to drain out. At this time you should also pull the axel itself (may need a little help from a hammer, its only held in with a C-clip like normal CV axels are). Once the axel shaft is out, the tube should pretty much come with it.

9. Once a majority of the fluid is drained, stuff a clean rag in the port left by the axel tube removal to prevent more fluid from coming out. Duct tape may be used here to retain rag position ;)

10. Now this part is nearly impossible to explain, but it can be done. Make sure the steering wheel is cut all the way to the right, this should move the pitman arm to the left side of the chassis. Now you need to push up, twist and side the diff housing over to the right side of the truck all in one shot. I wish you had asked this 3 months ago while it was still fresh in my head when I had to do this 3 times, lol. Once you get the stupid propshaft flange clear of the rear diff mount, it should pretty much come out.

You should be able to figure it out and hopefully I didnt leave anything out, but thats pretty much how I remember doing it. ;) goodluck.
 

InvisiBill

Active member
Re: Front diff swap tips?

Thanks for the info Morgan. I guess that's about what the manual says, but your instructions seem a whole lot better.

Timbo and I worked on this for quite a while today. We could not get that top diff bolt out. I bought and "modified" an 18mm wrench to hold the nut, but we're having a hard time getting at the bolt. There's only a few inches to the oilpan, and the ratchet handle hits on the frame (where the skidplate mounts) so you only get a tiny bit of swing. We were actually using a breaker bar I guess, because I couldn't find a 1/2" ratchet. I'm planning on picking one up and trying again, to see if that has less play and will turn the bolt better. But any tips on getting at that top bolt would be really appreciated.

For anyone else trying this, remember to loosen the axle nuts before you get the truck up on jackstands. Pull the wheels and go in through the sides for the axle-diff bolts. Doing them from below may be possible, but it was a whole lot easier for us to just pull the wheels and do it that way.
 

Loeryder

New member
Re: Front diff swap tips?

Captain Morgan said:
1. Buy an offset 18mm box wrench (if you dont have one), I also suggest buying a cheap one. I ended up modifying mine (cutting it shorter) to make it more user friendly. You will need this wrench in order to hold the nut inside the driverside frame rail for the upper diff mount bolt.

2. Remove propshaft.

3. Remove the 12 bolts that hold the CVs to the front diff (6 on each side). You may need a chisel and a hammer to pop the CVs off the axel shafts.

4. Remove the center link. Disconnect the tie rods from the center link on each side, followed by disconnecting the idler arm, then at the pitman arm.

5. Remove the diff mounting bolts.

6. Lift and tilt the whole diff assemble so that the passenger side axel shaft and tube are below the lower control arm.

7. Remove the 5 bolts holding the black axel tube to the diff case (be sure to have a pan under it, fluid should leak out).

8. Lightly tap around the axel tube to break the seal and allow fluid to drain out. At this time you should also pull the axel itself (may need a little help from a hammer, its only held in with a C-clip like normal CV axels are). Once the axel shaft is out, the tube should pretty much come with it.

9. Once a majority of the fluid is drained, stuff a clean rag in the port left by the axel tube removal to prevent more fluid from coming out. Duct tape may be used here to retain rag position ;)

10. Now this part is nearly impossible to explain, but it can be done. Make sure the steering wheel is cut all the way to the right, this should move the pitman arm to the left side of the chassis. Now you need to push up, twist and side the diff housing over to the right side of the truck all in one shot. I wish you had asked this 3 months ago while it was still fresh in my head when I had to do this 3 times, lol. Once you get the stupid propshaft flange clear of the rear diff mount, it should pretty much come out.

You should be able to figure it out and hopefully I didnt leave anything out, but thats pretty much how I remember doing it. ;) goodluck.

right click copy - right click paste.

No, I can't tell you have done this 2 or 3 times in the recent past... :lol:
 

Captain Morgan

Moderated User
Re: Front diff swap tips?

the biggest tip out of all that was the offset 18mm box wrench, thats the big lifesaver out of all of it.

to get to the top bolt, find the SHORTEST 18mm socket for 1/2 drive. I actually found one at Autozone I think, it was some weird off brand, it has a red stripe around the top of the socket, and its actually tapered in there. That little bit of taper will help with clearance of the crossover pipe that I think gets in the way there. Along with the socket, I used a 1/2 drive universal (swivel) and a long 1/2 drive extension. I cant remember if I needed a breaker bar there or not, but if I did it was just to crack it loose and I might have left the universal off for that as well.
 

InvisiBill

Active member
Re: Front diff swap tips?

The socket is Duralast (red and blue label). I had that bolt out within 10 minutes of getting the socket home. The short socket plus my 2.5" extension fit around the crossover perfectly.

Captain Morgan said:
8. Lightly tap around the axel tube to break the seal and allow fluid to drain out. At this time you should also pull the axel itself (may need a little help from a hammer, its only held in with a C-clip like normal CV axels are). Once the axel shaft is out, the tube should pretty much come with it.
I've never done anything with any CV axles before, so "normal" means nothing to me. What exactly is the process for removing the axle? Do I have to find and remove the C-clip, or just whack it and it will pop out? Do you think there's any way to do it without removing the axle and tube? I'd rather not take the new diff apart if I don't have to (because I'm clueless and lazy).

Captain Morgan said:
10. Now this part is nearly impossible to explain, but it can be done. Make sure the steering wheel is cut all the way to the right, this should move the pitman arm to the left side of the chassis. Now you need to push up, twist and side the diff housing over to the right side of the truck all in one shot. I wish you had asked this 3 months ago while it was still fresh in my head when I had to do this 3 times, lol. Once you get the stupid propshaft flange clear of the rear diff mount, it should pretty much come out.
I realize that it's hard to explain this step, but I'm not sure if I'm twisting it the right way. To get it to clear that rear mount, should I be rotating it so that the axle tube mounting surface is facing down? My last attempt, I was twisting the diff around the axle line, so the front mount was lower and the propshaft flange was higher, but that left it sitting against the rear mount and the oil pan with nowhere to go.

I've got everything unbolted. It just needs to fall apart now, and for once the stupid truck won't do that.
 

canadian

sy in progress
Re: Front diff swap tips?

Captain Morgan said:
it has a red stripe around the top of the socket

rs_welcome.gif
 

InvisiBill

Active member
Re: Front diff swap tips?

Popped the axle and tube out of the old and new diffs, and got the old diff out. Now I'm trying to make the new one fall up into place...

Pictures of the carnage to be taken soon...
 

Timbo

SyTy Stalker
Re: Front diff swap tips?

If you know what you're doing and have everything you need at hand, probably 2 hours. Otherwise, most of your time will be taken up by backtracking and going to the tool shop.
 
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