Front Differential (1 Viewer)

[smarch678]

Hey all!

I just picked up my first Land Cruiser...1991 with 173k miles on it. I was told it needed new ujoints up front. I just got it back from the mechanic and he said the joints are fine, but my front diff needs replacing. Ugh.

I'm a newbie when it comes to this kind of stuff. Do I find someone to rebuild it? Do I find a used one online or at a junkyard? If I find one at a junkyard, how do I know if it's good? Am I better off just getting a whole front end with this kind of mileage?

Any recommendations are much appreciated.

Thanks!

 

[Landseer]

The diffs on the 80 very seldom fail, especially after 173k miles. I'd get a second opinion on this, what symptoms are you seeing?

 

[Malleus]

Here's a recommendation: get a second opinion. Unless the front axle sounds like a coffee grinder, your diff is probably OK. I mean it'll be really loud. You'll know it. Bad U-joints clunk when you change direction, park to reverse or neutral to drive. That's an easy diagnosis.

You have no miles on that truck.

There are many options. Report back when you know for sure what you need.

 

[shocktower]

I would go read the slee's n00b info page and find another mechanic he don't know what is going on .

Oh and the mandatory welcoming salute

 

[Malleus]

Oh, I almost forgot, welcome to the addiction.

 

[gummycarbs]

Since they rarely go bad, if yours is actually bad then get one at a junkyard. If you're not aware, the Land Cruiser uses a different setup than most. The entire differential assembly comes out the back of the axle housing (the 3rd member).

You 'just' have to pull the axles out a few inches (which requires the same level of disassembly as for repacking the Birfields), remove the drive shaft, and remove the ring of nuts around the differential. Then you can pull the whole thing out. It's really heavy.

You can find parts on car-part.com. I think it's called the "carrier assembly" on their site, but I'm not sure if that includes the output shaft, bearing, seal, and housing.

Edit: I think you can replace the output bearing and seal without pulling the 3rd, and those are much more likely to go bad than the differential itself, especially if you have a lift and had a vibrating front drive shaft. Someone correct me if I'm wrong.

 

[smarch678]

The diffs on the 80 very seldom fail, especially after 173k miles. I'd get a second opinion on this, what symptoms are you seeing?

There is a pretty significant clunk when I put it into gear as well as when I step on the gas and again when I let off the gas.

 

[smarch678]

Th

Since they rarely go bad, if yours is actually bad then get one at a junkyard. If you're not aware, the Land Cruiser uses a different setup than most. The entire differential assembly comes out the back of the axle housing (the 3rd member).

You 'just' have to pull the axles out a few inches (which requires the same level of disassembly as for repacking the Birfields), remove the drive shaft, and remove the ring of nuts around the differential. Then you can pull the whole thing out. It's really heavy.

You can find parts on car-part.com. I think it's called the "carrier assembly" on their site, but I'm not sure if that includes the output shaft, bearing, seal, and housing.

Edit: I think you can replace the output bearing and seal without pulling the 3rd, and those are much more likely to go bad than the differential itself, especially if you have a lift and had a vibrating front drive shaft. Someone correct me if I'm wrong.

Thanks so much for the reply. I am pretty mechanically inclined and would be willing to try and tackle this...however...I lack the tools and resources. Just moved into a new area and know no one to help.

 

[smarch678]

Oh, I almost forgot, welcome to the addiction.

Thanks! Yes....this is a rabbit hole for sure. Super excited to have a project car. Already order wheels and tires (they were in bad shape) and Al's Liner is on its way! Just moved to Durango CO so there are LOTS of places to go. I will slowly be transforming this into the weekend off-roading/camping truckster for the family.

 

[Malleus]

There is a pretty significant clunk when I put it into gear as well as when I step on the gas and again when I let off the gas.

U-joints. About $80 a piece; you need at least two. Get new nuts and washers; your old ones have rounded corners and they're rusty.

 

[madisonr34]

Sounds like a u joint to me. Get under the car and visually inspect the u joints. Grease them up and see where the grease comes out of the u joint seals... you can also check them for play. Just wiggle them.

 

[Malleus]

EDIT: grabbed the wrong list. Keep this for next time, or do both shafts at the same time. I would.

Front:
2x U-Joint 04371-60070
4x Nut 90179-11005
4x Washer 90201-11013
3x Grease fitting 96451-00600 (a good idea since you broke one getting the U-joint off)

Rear:
2x U-Joint 04371-60210
4x Bolt 90105-11013
4x Nut 90179-11005
4x Washer 90201-11013

Notice the rear U-joint has bolts and nuts, the front studs are in the flange. Same nuts and washers. 3rd grease fitting is for the spline.

 

[smarch678]

U-joints. About $80 a piece; you need at least two. Get new nuts and washers; your old ones have rounded corners and they're rusty.

That's what I thought...thanks so much...you guys are awesome.

 

[smarch678]

Sounds like a u joint to me. Get under the car and visually inspect the u joints. Grease them up and see where the grease comes out of the u joint seals... you can also check them for play. Just wiggle them.

Will do! Thanks!

 

[smarch678]

For the FRONT propeller shaft:

Front:
1x U-Joint 04371-60070
4x Nut 90179-11005
4x Washer 90201-11013
3x Grease fitting 96451-00600 (a good idea since you broke one getting the U-joint off)

Rear:
1x U-Joint 04371-60210
4x Bolt 90105-11013
4x Nut 90179-11005
4x Washer 90201-11013

Notice the rear U-joint has bolts and nuts, the front studs are in the flange. Same nuts and washers. 3rd grease fitting is for the spline.

Thanks so much!! Never done a ujoint myself...it is something I can do with standard tools or do i need specialized tools for the job?

 

[Landseer]

Check the driveshaft bolts before you buy new ujoints, they can sometimes come loose causing a driveline "clunk".

 

[gummycarbs]

Thanks so much!! Never done a ujoint myself...it is something I can do with standard tools or do i need specialized tools for the job?

You really want some specialized tools to do it properly. People (including me) have done them with vises, hammers, and drifts, but I *strongly* recommend doing them the correct way. I wince every time I think of the flanges I've damaged out of my own ignorance...

Watch a few videos in this series to see the correct way to do it:

 

[Malleus]

Thanks so much!! Never done a ujoint myself...it is something I can do with standard tools or do i need specialized tools for the job?

You need snap ring pliers. Get the kind that you can switch from inside to outside, with multiple tips. Less tools to lose.

12-mm socket and breaker bar, with a 12-18" piece of pipe. To fit over the breaker bar.

Beer for your busted knuckles.

Sometimes a bench vise is handy to press them out of the yokes. You can beat them out, but you can also break the yoke if you're not careful. Go ahead and buy a 6" vise. Thank me later.

 

[Malleus]

You really want some specialized tools to do it properly. People (including me) have done them with vises, hammers, and drifts, but I *strongly* recommend doing them the correct way. I wince every time I think of the flanges I've damaged out of my own ignorance...

Watch a few videos in this series to see the correct way to do it:

Yeah, get a 14" arbor press. Let me know when you do. I want to come over and borrow it.

 

[Malleus]

Seriously, I'd use the press if I had one. I just never could find one I liked for less than a mortgage payment, and it takes up too much room for the little use it'd get.

A large bench vise is a press on its side. You'll get more use out of it.