Which Differential Carrier Assembly do I have?

Hello everyone!

Yesterday as I was pulling out of my neighborhood, I heard a loud thump and started feeling the truck jerking like something was holding it back followed by more thumps and bangs. While limping it back into my neighborhood I could hear it coming from the rear diff so I drained the oil to find quite a bit of metal shavings in there.

My differential carrier assembly is definitely going to need rebuilt or replaced but I was curious as to how I can find out what kind mine is? I have an 00 tundra 4.7 4wd and from what I've read it looks like there's a gear ratio of 3.91 and 4.1 if I'm correct and there is also locked and unlocked. How do I know which one I have?

All advice is greatly appreciated. thank you!

 

Iirc 4.1 and 4.3 were for the 3.4p v6.

Most likely you have 3.91 and an open diff. You can put your vin into the toyota owners website to see if LSD was installed at the factory/dealer.

Does your diff have the LSD oil sticker?

Here's a fresh one I added to mine after installing an LSD.

 

I did not see a sticker on mine but I’ll check again and I’ll plug in my vin number and check it out. I will be adding a sticker to identify it later for sure

Thanks assassin for the info

 

Let us know how it worked out. Mine just took a dump too.

 

Dang I’m sorry to hear about that. Luckily it’s not a difficult job to do unless you rebuild the diff yourself. I’ve still got my old broken one I’m going to rebuild for later use. I payed $600 for a used 3.91 non lsd and I believe a rebuild was around $900 at a shop.

I removed the diff carrier to find it was missing several teeth all around the different gears. I still don’t know what could have caused it because I baby that truck but anything can happen. I picked up a used diff carrier from somebody because I just needed it running asap. I slapped the new/used one in, filled up the pumpkin and now the problem is resolved. however i am hearing a faint knock like something might be bumping around in there again so I will be inspecting it again soon to make sure everything is correct.

something that will probably save you time or maybe you can make the discovery I couldn’t, there is no gasket for the rear diff. They say to use rtv which it worked good for me so far. No leaks at all.

 

You definitely have the 3.91 rear. AC V8 4x4's all came with them. The 4.10 came in the CrewCab models with v8's later.

 

Wow - I replaced the real axle about 8 years ago due to rust. Had the old 3.91 diff hanging around for 2 years - no one wanted it. Finally just scrapped it. I would think there's probably a bunch of used ones out there.

 

Thanks for the response! Yeah, I baby mine too, but not sure how the previous owner treated the truck. My tech said I have to replace the wheel bearings as the nice little metal flakes migrate out from the diff and ruin the bearings. He did note the axles are possibly sealed (I need to check that out) and may not have to do the bearings. I'm leaning towards finding a used one. Comes at a rotten time, on medical leave and disability and boy does this put a hurt to my finances! I don't have a shop and tools, so the labor is going to be gnarly. Hope yours stays together, keep me posted. Mine is still drivable, but boy is it loud! Tech said when it blows, just put it in 4WD and drive it home, LOL!

 

Axle bearings are sealed... they'll be fine.

 

My luck finding a 3.91 wasn’t bad. I also found a 3.91 limited slip the guy was asking $950. They are out there you just have to find them. I found a lot of junker first gen acc cabs in cali but I wasn’t going to make that drive being in Colorado

I tried pulling up my trucks history by the vin and a while ago it said the rear diff locked up while going about 50 and sent the driver into a skid… supposedly it was fixed by a 3rd party mechanic. not really what a truck owner wants to hear haha.

I hope it goes easy for you without hurting the wallet to much. If you decide to tackle it yourself it’s honestly a simple fix as long as you find the correct diff. Plus you can do it with basic tools. Here’s the steps I took to fix mine.
- drain diff fluid
- jack up the rear & removed both tires
- disconnect and plug up the brake line
- disconnect the e-brake cable from the back of the brakes
- remove the 4 mounting bolts holding the axle to the diff on both sides and pull them out a few inches
- Remove the 3 bolts to the drive line where it connects to the carrier and set the driveline to the side (preferably on a jack stand)
- remove the bolts to the diff carrier and you will be able to pull it out.
- clean out the debris as best as you can
(If I’m missing any steps please correct me)

I don’t remember the bolt sizes but like I said it was just basic tools. then just repeat the steps backwards and remember rtv to seal the new carrier when you reinstall it and bleed the brakes. This will definitely save you from spending a lot at the shop. After doing everything I spent around $700.

Worst case there is a way to rig the carrier and keep it in 4wd from what I’ve heard. It will be a front wheel drive if you do that and I’m not sure if it damages anything tbh. There’s a guy on YouTube that talks about doing it although he has a white double cab I believe. I would recommend researching it and talking to someone that has actually done that before you try it because I feel like that is a last resort kinda thing and I’m not familiar with the exact steps to doing that.

Good luck to you friend and let us know how it goes

 

I'm not going to do a used one, having trouble finding any new out there in the aftermarket. Toyota wants up to $2150. Lowest I've found (and I've spent hours searching) is just over $1400.00. Yikes.

 

Why not just get a whole axle?

 

Axle failures are quite rare on these trucks. I'd have no hesitation going with a used carrier or a used complete axle. In fact, it would be my first choice.

 

I'm not able to do the work myself. Shop won't warranty used parts, and honestly, I don't want someone else's beaten up part and be back at square one. Appreciate the suggestions! Just hoped there were more affordable aftermarket solutions. Thanks

 

You might consider a rebuilt diff, with new innards https://eastcoastgearsupply.com/i-788575-tacoma-8-4-non-eld-t100-tundra-3rd.html