Differential failure!

hello tacomaworld,

So a little back story to this whole ordeal... for about two weeks now my truck has been randomly been making an awful bang sound, and when it happened it felt like the back tires would lock up for a split second then free up again.

The first time it happened i was driving in a straight line doing about 60mph. i got it home that night and my dad said theres no way to really figure out what was wrong unless we just started tearing things apart, so his suggestion was to just drive it till it broke completely. since then it has done it a couple more times while taking off coasting and driving normal. It had done it once more, this time was pretty violent, and i said thats it and tore into it.

Soo tonight i pulled the third member and what i found made me .
turns out 8 of the ring gear bolts had completely come out and were just lying in the bottom of the axle housing. the other four were about finger tight.

Does this happen often? ive never heard of this happening to anyone, and what would cause them to just back out like that?? Im not sure if anyone has ever done any work to the differential, but it does have the stock gears in it. Anyways i was wondering if i should just buy new ring gear bolts, all the gears seem to be fine. or buy my friends front and rear axles out of a 98 trd? hes giving me a pretty good deal.


heres some pictures of the carnage..




the bolts that were floating in the housing


this is what i cleaned out of the housing



thanks for any input

 

I have heard of this happening before, not on tacomas though... bolts came loose on those rigs due to improper torque...

Everything has a tendancy to loosen over time..

 

Yeah it's happened definitely. Not sure about on a Tacoma though but probably.

Was it stock or had somebody been through it?

To help to insure this doesn't happen the ring gear and carrier need to be absolutely flush and smooth. If there are high spots they need to be filed down. Both need to be very clean and you need to use new ring gear bolts with a little bit of loctite. Also torquing the ring gear bolts to exact specs and in proper order is critical. I would say any of these things could have gone wrong.
Don't re-use ring gear bolts.

 

I also have seen this before; but not on Toyotas.

Not a truck but: Actually, we have a Yamaha Rhino in the shop with the same problem. Googled the Rhino and we find out this has been a problem.

On cars and trucks, the only time I have seen this was in 2 different race cars. The ring gear bolts were not torqued correctly at installation.

We use Loc-Tight,just in case now. And torque to specs.

 

Buy the TRD rear axle! You'll need to swap the whole gosh darned thing though, not just the dif.
I don't think you would need to buy the front one too.

 

Are you sure about RED? red means you NEVER want to get in there. Maybe just use blue instead? Just asking, I don't know anything

Also, is it routine maintenance to torque these? I probably need to look back there if it is.

 

No should never need to be touched, and don't.

Blue would be fine, I'd rather have red.

 

Rather than have someone fix this diff it's probably cheaper to just buy a stock 3rd and swap em out.

IF NOT.

I personally would run your carrier, as I think the damage isn't severe, but I'd probably double check with someone that builds these diffs daily. I think if that's the only damage and theres no damage to your pinion or ring I'd have someone set them back up with new ring gear bolts. If you need new gears it'll be pretty costly.

 

Next time don't ask you-re father, about trucks anyway.
But I suggest to ask and consider his opinion for everything else, but trucks.

 

Ehh, not quite. I had to look it up to be sure,

I guess you can't totally go off color, but general rule:
purple = why bother
blue = medium
red = high, requires heat. I've heard it called 'red means stop', but other more colorful people call it "F___ the next guy"
green = special purpose version of red. The 290 is used to seep into cracks and porous metal. Probably about the worst idea ever for your diff, having loctite seep into the gears!

Found this handy dandy guide

 

put some green loctite on them or some LocTite #690 and i PROMISE you they will NEVER come off even if you try to get them off. The Ford Blue thread locker is just as strong as loctite green

 

You can get bolts with red locktite off without heat, its really not that big of a deal, just have to be a man to break it loose.
If you want permanent put some jb weld on the threads

 

Trying to find that but the one picture I came across was really obscure so I don't know where it is. Using the rear diff as an example, are you talking about the bolts on the cone-shaped housing that attaches to the pumpkin? Or are you talking about something inside? If it's inside I'm too much of a wuss to monkey around in there

EDIT: is it the pair of bolt heads in the 3rd pic of the original post that are still mounted?

I don't mean to hijack OP, I'm hoping to ask all the dumb questions for you

 

Ok, so first assumption was right (and apparently they are nuts, thanks for pic).

According to the torque specs they would be the "Differential carrier x axle housing" and require a torque of 33 lbs.

Chart

Anything on the front? There's an unholy amount of different bolts and specs

 

Well i guess now would be a good time to regear if you wanted too! Haha

 

Meh..half my taco has red locktite. No heat is ever needed to break something loose

 

Ha, you weren't around when I did my ball joints. I thought I wasn't afraid then.

Interesting, my guide has 33. Is your guide for 1st gen? (I guess I'm being a jerk by posting 2nd gen specs here - I thought this was in the tech section)

 

LOL it's the same guide. So your printout has both 18 ft lbs and 33 ft lbs. Customtacos is missing the page that has the exploded view.

I went and looked up the 1st gen guide - the install page says "Installation is in the reverse order of removal"
They just have the exploded view that shows the 18 ft-lbs, unless you accidentally look at the "3RZ-FE, 5VZFE w/o Diff Lock", which I'm guessing is mislabeled at 54 ft lbs!

 

Assuming it's about an 8.8 grade stud 33 ft lbs is probably correct for a 10mm stud.

Interesting the one says 18 though.


You'll notice though that the one that says 33 has 10 studs on a v6 diff.

E-locker says 11 studs and 18ft lbs.

Erik's diff page says the v6 diffs used 8mm studs. LOL I have no fucking idea.

Oh and the torque values for the FJ e-locker rear is 18 as well, shows the nuts and lock washers much clearer.


I'd say that chances are good that feeling it tight with a 3/8 ratchet will put you somewhere around 25 ft lbs which should be fine. Theres definitely a margin of error in there so whatever.

 

Hey guys sorry for the late reply to every one... But first off thanks for all the info and concerns! from what I've been reading from y'all and some other stuff I read on the Internet I think I'm just gunna but some new ring gear bolts and use RED loctite. I would love to buy the trd axle but it would be cheaper to just try to fix what I have seein how I'm in school full time and money's a bit tight haha

But if I do buy the axle and front diff ill have 4.10s if I'm not mistaken... He said there 4.11s??? And then I'd have an e locker! Haha decisions decisions