4th Gen Differential Interchange (Tacoma, FJ etc.?)

[RPS13]

I'm pretty sure the pinion bearing on my diff is out. I get a pretty high pitched diff noise starting around 30, it gets loudest around 40-45 mph, then by 65-70 mph it's mostly gone. Some harmonic gear noise on decel, along with a "gliding" bearing noise if that makes sense. Not a rough grinding, but the sound of a bearing loading up and making noise while it's working. I changed the fluid to Redline 80W-140, and it didn't really change things. Old fluid looked fairly old, and there weren't an excessive amount of metal shavings in it (just the normal fine fuzzy/grey gunk on the magnet).

So my question is - what other vehicles have a differential that swaps into a 4th gen axle no problems? Some cases from way earlier 4Runners look a bit shorter (yes, they're still rears as far as I can tell, not fronts), and some have an electrical connector that I assume is for a locker diff. So do Tacoma diffs swap in, what about FJ Cruisers?


I'm trying to widen the search net to get one at a reasonable price.


Or if someone here wants to sell me an OEM diff in good shape, that sounds good too.

 

[gm350reratliff]

I could be wrong but I think the FJ diff will swap in. The taco diff is a different story due to the taco having leaf springs and the 4runner having coils. Not sure if the widths are even the same.

 

[RPS13]

I'm more thinking about doing just the differential itself rather than a full axle swap. Or is the full axle swap easier from an install perspective?

 

[superman3043]

I'll have one available in 2 weeks for you if you can hang on. You'll have to pay shipping on it of course. There's also one available on my local craigs list for $150 which I think is a screaming deal. If you want, I can link you. Good luck.

 

[RPS13]

I've lived with it for a while, so 2 weeks sounds doable to me. What sort of pricing would you want for it? I've shipped full Nissan R200's that weigh about 80 lbs for $38-45, so it shouldn't be that horrible on shipping. I think the Toyota diff is lighter being a mostly open case design.


It doesn't look that hard to change out the diff - roughly 2-3 hours or so right?


Also - I see looking at the FSM that the 4WD and 2WD 4Runners have a different input flange. I guess I can just swap that over?

 

[superman3043]

I've lived with it for a while, so 2 weeks sounds doable to me. What sort of pricing would you want for it? I've shipped full Nissan R200's that weigh about 80 lbs for $38-45, so it shouldn't be that horrible on shipping. I think the Toyota diff is lighter being a mostly open case design.


It doesn't look that hard to change out the diff - roughly 2-3 hours or so right?


Also - I see looking at the FSM that the 4WD and 2WD 4Runners have a different input flange. I guess I can just swap that over?

I'd be willing to do $125 for the part plus shipping so it'd come in less than the CL guy here.

Yeah, I'd say you're about right on the labor. I'll know a little better after I do mine. I understand you don't have to fully pull your axle shafts, that there is enough slack in the lines to allow you to pull them just far enough to disengage them. You just need to support the hubs to keep them from off of the seals. It would keep you from having to disassemble the parking brake, which I understand is a PITA to put back together.

I didn't know about the difference in flanges though. Here is a link to the CL guys add:

**** Toyota Pickup or 4Runner "3rd Member" Rear Differential ****

He's had it for up for a while, because he started out asking $200 for it. If you want to go that route, please feel free. His application seems to fit yours almost exactly (2WD, 2007, V6)

 

[RPS13]

Bah.. typed out a long response and the server busy msg killed it.


That guy's diff has the same problem mine does - pinion bearing noise. He also didn't seem to understand that stack up tolerances aren't held super tight on things like bearing races since you have to shim the diff at the end, so replacing the pinion bearing likely means having to reshim it. He seemed to think $150 for a worn out stock diff was an absolute bargain...


So I'm still interested in your diff if it's in good shape.

I do have to wonder what's up with these pinion bearings, as there are quite a few cases popping up with a casual search. Seems undersized for the application.

 

[Hulley]

I had to rebuild mine earlier this year. I paid a shop $650 total with genuine Toyota parts. I think that was the way to go, did not want to get a used diff only to have the problem again. I also had the front diff and transfer fill with Redline fluid at the same time.

 

[superman3043]

Bah.. typed out a long response and the server busy msg killed it.


That guy's diff has the same problem mine does - pinion bearing noise. He also didn't seem to understand that stack up tolerances aren't held super tight on things like bearing races since you have to shim the diff at the end, so replacing the pinion bearing likely means having to reshim it. He seemed to think $150 for a worn out stock diff was an absolute bargain...


So I'm still interested in your diff if it's in good shape.

I do have to wonder what's up with these pinion bearings, as there are quite a few cases popping up with a casual search. Seems undersized for the application.

Gotta love it. Yeah, I always make sure that I copy my messages before submitting them for that very reason.

Yeah, mine's good to go as far as I know. The only reason I'm removing it is to replace it with an E-Locker 3rd from an FJ, which coincidentally had... A bad pinion bearing (go figure). Starting to sound like a flawed design. I guess you aren't interested in a rebuild, which is what I'm doing to that diff. I ordered a master install kit from Chase at East Coast Gear supply. Also a solid pinion spacer. Hopefully this will prevent any future issues. I guess you could go this same route, but I'm pretty much offering you a plug in solution for less than what I paid in parts, so...

I'll let you know what's up when the job is done man. Feel free to keep searching and just let me know if you come up with an alternate solution. No big deal to me, I was just gonna keep it around as a spare in case somebody needed it anyway. Chase only offered me $50 plus shipping for it, so I figured for that, I'd just hang on to it.

 

[RPS13]

Drop in and go sounds good to me right now. Maybe I can rebuild my current one later if it comes to that...

No wheeling for me (as if the 2WD wasn't enough of a hint ), just the occasional towing of my fast toy and daily driving. So a good condition stock diff sounds good to me.


Shoot me a PM whenever you get closer to pulling it out and we'll work out payment and shipping.

 

[superman3043]

Will do.

Off topic, but I just realized that you're the BBK retrofit engineer that I was talking to before. Any progress on your Wilwood kit? After that thread, I gave more thought into getting a 3D printer to bang out prototypes on. My (day job) company is literally right next door to one of the biggest 3D printer companies around. You pull the trigger on one yet? Right now, my machinists treat us so good, I really can't justify the purchase. That plus the fact that we just bought a Bridgeport for the speed shop, I think I'll be putting off the 3D printer purchase for a while... One day though.

 

[RPS13]

I didn't have an immediate need, or necessarily the time to put one together now, so I went with a Kickstarter project - the Kossel Pro. Should get it in a few months which works for me. I don't have the budget or the need for a commercial 3D printer. Plus I like tinkering with stuff when I can find the time.

Honestly, the tepid interest shown here on aftermarket calipers has me really not even thinking about the brackets. But maybe some time next year I'll take some measurements and bolt up a set of caliper on some 3D printed brackets just to show it fits and see what happens.

It just doesn't work trying to make 3 or 4 of something. People think you're ripping them off with the price you charge, and even then you're not making much if anything off the deal, and you can't blame the machinist because he's got to sit there and generate the G-code and check each step and dimensions on the initial setup whether he makes 1 or 1,000. So it all trickles down, no one really makes any money in the chain, and the end consumer feels they didn't get a deal.

 

[cwooplay]

Gotta love it. Yeah, I always make sure that I copy my messages before submitting them for that very reason.

Yeah, mine's good to go as far as I know. The only reason I'm removing it is to replace it with an E-Locker 3rd from an FJ, which coincidentally had... A bad pinion bearing (go figure). Starting to sound like a flawed design. I guess you aren't interested in a rebuild, which is what I'm doing to that diff. I ordered a master install kit from Chase at East Coast Gear supply. Also a solid pinion spacer. Hopefully this will prevent any future issues. I guess you could go this same route, but I'm pretty much offering you a plug in solution for less than what I paid in parts, so...

I'll let you know what's up when the job is done man. Feel free to keep searching and just let me know if you come up with an alternate solution. No big deal to me, I was just gonna keep it around as a spare in case somebody needed it anyway. Chase only offered me $50 plus shipping for it, so I figured for that, I'd just hang on to it.

Hello!
I know this is years later but I have the same differential problem as stated above and am looking for a replacement for my 4th gen, V6, 2006 4WD.
I have a budget of about $750 which should be able to get me a diff from ECGS but I was wondering how your FJ swap went? Was it a lot of work getting it in the 4runner?
You think I could do it with my budget or would you happen to have any other leads good plug n plays?

Thanks!

 

[superman3043]

Hello!
I know this is years later but I have the same differential problem as stated above and am looking for a replacement for my 4th gen, V6, 2006 4WD.
I have a budget of about $750 which should be able to get me a diff from ECGS but I was wondering how your FJ swap went? Was it a lot of work getting it in the 4runner?
You think I could do it with my budget or would you happen to have any other leads good plug n plays?

Thanks!

Goodness talk about a throwback. Look, TBH my retrofit probably ended up being more problematic than most. If anything, I'm thankful to have done it, if for nothing else, purely for the learning experience. The ROI for the project has been very low but YMMV. Had to do it all over again, I'd probably just put in a aftermarket locker and that would be my personal recommendation for somebody looking into it. After everything was said and done, I'm really not sure if I saved anything in the long run.

I've got a lot of info in my build thread spread out over many years and posts, that you could sift through to get a feel for my experience with it, but I'll warn you, it could be a long read. If budget is fixed then just get the replacement with a solid spacer and call it a day. If there's flexibility and you really want to do a locker while you have this chance, just go ahead and reach now and spend the extra for a locker, eat Ramen, and have zero regrets.

Hope that helps. Good luck.