Identify this part of the driveshaft?

Greetings,

What’s the pictured part called?

A month or so ago I stated hearing a clanking sound when driving over a bump or pothole. I thought it was coming from the spare tire chain since I had recently lowered it to check the pressure. I really wasn’t too concerned about the noise. Looked underneath the truck a few times to make sure everything “seemed” tight and in place.

This past Saturday we left for vacation (10 hr drive) and shortly into the trip on the interstate I went over a bump and the truck started making a new noise. The best was to describe it is that the reared howl changed to a metallic grinding. Only seemed to happen when feathering the throttle. First fuel stopped looked underneath and didn’t see anything obvious and the truck seemed normal. The only thing other than the noise was it felt the clutch was slipping in 1st and 2nd gear. But that could’ve been in my head. At the second fuel stop I checked the underneath again and found what you see in the pictures. We were in the middle of no where at a sheetz and I feared our trip would be delayed immediately as the one remaining screw left the driveshaft on borrowed time. Luckily there was an auto parts store across the street that was able to buy a socket set and bolt at. Fixed the truck and it performed flawlessly on the rest of the trip.

So I have a few questions:

what is the part called in the pictures?

assuming the dealer is unable to provide the correct bolt, just a grade 8 bolt would work?

what’s the torque spec for this bolt? It’s currently tight as I felt it should be.

I recently had the rear differential seal replaced under warranty. Would this part need to be loosened and/or removed to replace the seal? I assume it would. And if it was, it makes sense since that’s when the clanking started.

Assuming this is the dealerships fault, what is the torque spec of the bolts on the rear differential? I want to check those bolts when I get home because I have zero faith in what they did for that repair now.

Thanks,

 

carrier bearing 27lbf

not sure bolt size but i think m8

 

Oh dang, that's no bueno. That's the center support bearing, or more commonly referred to as the carrier bearing. If they decided to remove the rear driveshaft in its totality for the seal, then yes those two bolts would be removed. I would take it in and explain what happened and have them document in case there are any u joint or bearing or even rear diff issues in the future.

 

rear diff 18lbf

 

Driveshaft center support bearing. Metric thread, gonna go with an M12, not sure on thread pitch. Torque spec is 45ft#'s

 

I know the bolt size, I was able to get one from the parts store. I’m not sure the proper bolt material for the permanent bolt.

 

Thank You!

 

There are some torque specs that are just not enough, that is one of em. If you look up the torque spec for the ubolts, it says something like 37ft#'s. 37 is not enough, they need to be 85-90ft#'s. So thats why I recommended 45ft#'s for the 2 driveshaft center support bearing bolts. It is also what ARB/OME recommends as well.

 

on a 19? weird... but yeah.. these peeps are right.... Center support bearing... kind of a pain to replace... just make sure to mark the orientation of the drive line assembly... it is balanced as a unit and it needs to be reinstalled the way it came out...

 

maybe 37 is enough. it also recommended to use red lock tight so thats probably why. Mine are at 85-90 though with locktight

 

Sighs......typically the drive shaft could be moved out of the way to remove the diff front seal, but I have not done one on a tacoma so it is possible the carrier bearing support would need to be removed.
IWould take these photos to the dealership general manager just to let them know this happened.

It is IMPOSSIBLE for these 2 fasteners to just fall out especially in the photo there is no long term sign of them being loose and making a wear mark on carrier bearing support NOR did they snap.

Being a 40+ year mechanic it really pisses me off to all ends seeing this kind of thing.

 

Right, this isn’t something that just happened. The truck has 5k miles, a year old and has been driven normally on road. I’m almost 100% sure it was neglect of the technician. I expect the dearer to dismiss it as their fault.

I’m glad I caught it before it was a catastrophic failure that caused real damage.

 

you are extremely lucky that prop shaft didnt....ahem taco... on you going down the road.

BE persistent when you talk to the GM bring in your documentation of the visit (ask to discuss this in their office) and have them bring in the service manager....the mechanic should have a comeback on their record.
This was no little issue. Show them a bill for the fasteners and YOUR TIME FIXING THEIR ISSUE. Even if they laugh it shows you were diligent in YOUR work as the mechanic was NOT.

Let the GM know that your review sent by Toyota or the dealer will NOT be favorable either way.

 

Even if they didn't loosen it to replace the seal it's still their problem because it's still under warranty and bolts shouldn't be coming out .

 

Propeller shaft centre support bearing, torque spec is 27 lbf-ft (36 N-m) bolt part number is 90119-A0175, it's an M10x1.25 bolt with a large captive washer, similar to this:



For the prop shaft to rear differential pinion flange nuts (or bolts on the smaller differential) the torque spec is 65 lbf-ft (88 N-m).

As for whether the needed to be removed to do the pinion seal, probably not, but that doesn't mean they weren't. If I were doing the job I'd probably not touch them, but I'm sure there are also many techs who would prefer to just get it out of the way (also because your truck has studs on the pinion flange, it may have needed to move further, but I can't say for certain). Either way, it would be mighty suspicious if they fell out and the dealership hadn't touched them. It seems far more likely that a mistake was made.

Jeff

 

Thank you! I can at least order the correct bolt from the parts department when we get home.

 

Why not make them tow it back due to driveability concern. This is their fault; they need to deal with it on their dime.

 

Not worth the aggravation. The closest dealership is 30 miles away to start the process at. I don’t imagine Toyota would tow it 600+ miles to my home dealership. Plus I’d rather not cut into my vacation.