Front dif?

[Cherryred98]

I’m pretty sure this is in the wrong place, hopefully someone can fix it. I have a 98 k1500 Silverado. I grenaded the rear 10 bolt differential. My uncle has a 94 z71 that he is parting out so I took his rear differential. It is a 14 bolt, it bolted right in I just had to have a u joint sized. Now the delema. I’m guessing that the front differential in the 94 is different from the one in my 98 (I know the gearing is different) I’m sure it’s probably stronger because of the 14 bolt in the rear, but my question is, will that differential be a direct swap? Or will I have to change cv axles or other stuff? If I don’t have to change the cv axles obviously I don’t want to lol I just wanna be able to put it in 4wd without worrying about grenading my t case b

 

[GoToGuy]

First, gotta have all the years, makes , models, involved. You have to be complete when giving info , and describing what's going on. Without basic info, how do you get an answer? And two different size 14 bolt, six lug and eight lug wheels.

 

[b454rat]

Seeing how he did mention a K1500, and the parts truck was a 94 Z-71, and that had the option of the 14 bolt rear, and they didn't make 8 lug Z-71's back then. But the front diff will 100% bolt in.

 

[Cherryred98]

First, gotta have all the years, makes , models, involved. You have to be complete when giving info , and describing what's going on. Without basic info, how do you get an answer? And two different size 14 bolt, six lug and eight lug wheels.

I’m sorry I thought I was clear enough, but I realize I did leave out important info, my truck is a 1998 Silverado k1500. The parts truck is a 1994 z71 k1500. Both trucks are 6 lug

 

[Cherryred98]

Seeing how he did mention a K1500, and the parts truck was a 94 Z-71, and that had the option of the 14 bolt rear, and they didn't make 8 lug Z-71's back then. But the front diff will 100% bolt in.

That’s good to know I was reading on a different thread about the differential actuator changing in 97? If they both have the lever on the floor all the wiring and cable should be the same right?

 

[b454rat]

I'm not sure on the wiring, but if there is a difference it's easy convert.

 

[evilunclegrimace]

The '98 passenger side axle tube is most likley cast iron compared to the '94 tube which is aluminum. The cast iron tube also doesnt have the small engagement switch and is shorter where the actuater screws in to the tube elimaniting the need for the steel spacer puck. It is also a good time to change the seals while the diff is out. Make sure to follow the correct procedure or you will have to remove the tube to realign the thrust washer that can slide out of place when the axle is pulled.

 

[Cherryred98]

How hard is it to swap the tube? Unbolt it and it should just pull out and be able to swap, right? I’ve seen LT tolman on YouTube do it on a s10 front end I would think it’s the same just bigger? I know changing the seal on the passenger side has more that goes into it

 

[evilunclegrimace]

How hard is it to swap the tube? Unbolt it, split the case and undo the c clip on the spider and it should just pull out and be able to swap right? I’ve seen LT tolman on YouTube do it on a s10 front end I would think it’s the same just bigger?

It is easy enough, there is not a "C" clip on the spider. Engage the front diff into 4x4 before you remove it is possible, if not stand it on end short side down and drive the long axle up by striking the flange to get the wire clip holding the axle in place to disengage.Remove the actuator, replace the axle seal, unbolt the 5 bolts holding the tube on and clean the mating surfaces. You can see the shift fork and sliding collar that locks the axle gear to the stub . There is a thrust washer under the axle gear that can slide out of place. lift the short axle gear out clean the lube off the contact surfaces on BOTH side of the thrust washer and stick it in place with some assembly lube.
I take the axle gear and tap it on to the axle after the axle is back in the tube( pay attention to the orientation) and make sure that the gear is retained by the wire clip that is on the inner spline. Apply the proper sealant to the mating surfaces and carefully reinstall the axle tube assembly back on to the diff case making sure that you don't move the thrust washer. I find it helps to use a piece of wooden dowel about 12" long inserted though the acuator bore to hold the shift fork plunger down to keep the thrust washer from sliding out of position.
It sounds alot more complicated than it is.

 

[Nad_Yvalhosert]

@Cherryred98 Have you checked the gear ratios? If they're the same, there is zero need to swap front differentials. Leave the OE front alone and you won't have to rewire it.

The 1500 4x4s and 6 lug 2500s used the same front diff case. Same size, same part numbers (in the same year). The difference is between the type of actuators used to activate 4x4 which changed sometime in '97.

I upgraded my '88 1500 4.3L years ago. An '88 6 lug 2500 bolted right in. 3.73 to 3.42, so I used both F&R diffs. TLA just plugged in. As @evilunclegrimace noted, you could swap the pass side extension housing, but check the gear ratios first.